CN1162283A - Coated abrasive article, method for preparing same, and method of using - Google Patents

Abstract

A coated abrasive article having a backing and an abrasive layer coated on the first major surface of the backing, wherein a cross-section of the abrasive layer normal to the thickness and at a center point of the thickness has a total cross-sectional area of abrasive agglomerates which is substantially the same as that at a point along the thickness which is 75% of a distance between the center point and the contact side; a coated abrasive article comprising abrasive agglomerates in the shape of a truncated four-sided pyramid; a method of making the coated abrasive article; and a method of abrading a hard workpiece using a coated abrasive article.

Description

Coated abrasive article and preparation thereof and using method

Invention field

The present invention relates to a kind of abrasive material that has, be applicable to and grind as the coated abrasive article of the very hard components of hardened steel, cast iron, pottery and rock material and make the method for this coated abrasive article.The invention still further relates to and use this grinding tool to grind the method for hard components.

Background of invention

The grinding tool that contains abrasive grain is being used for grinding and/or polishing various materials in the purposes widely, and these materials are called workpiece.These purposes comprise that the high stock removal of the high pressure from the metal forging grinds the polishing up to glasses.

Abrasive grain comprises abrasive particle and/or its agglomerate, and various performances can be provided for the application of abrasive industry.The selection of abrasive grain type is generally depended on the operating characteristics of the physical property of particle, the workpiece that needs grinding, the surface property that will reach, abrasive grain and is the economy of the selected abrasive grain of this concrete purposes.

Aluminium oxide is that alumina is a most frequently used abrasive grain in producing as the coated abrasive article of sand paper.In a lot of application that for example are coated with facing sand mill, metal grinding and plastic polishing, can use aluminium oxide.Carborundum also is a kind of common abrasive material, it is generally acknowledged that it is the sharper keen material of ratio aluminum oxide, is mainly used in the application of timber, lacquer painting and glass grinding.The diamond and the cubic boron nitride (claiming " CBN " later on) that are generally known as " superabrasive " are used in particular for grinding the stone parts as hardened steel, pottery, cast iron and rock material.Diamond generally is the preferred superabrasive that is used for nonferrous material, and CBN generally is the preferred superabrasive that is used for as the iron type materials of hardened steel.Yet as the superabrasive of diamond and CBN, its cost is expensive 1000 times of aluminium oxide, a carborundum than conventional abrasive material particle.So, when using super abrasive grain, wish to give full play to its effect.

As noted earlier, abrasive grain can be single particle or agglomerate.The abrasive material agglomerate is made of the particle that many single abrasive particles are bonded together adhesive.During grinding, agglomerate generally can be corroded or be broken, and the abrasive particle that the venting grinding was used exposes new abrasive particle.This agglomerate can be used in the abrasive product as coated abrasive article, non-woven grinding tool and emery wheel, and long service life, abrasive grain that efficient is high are provided therein.

United States Patent (USP) 2,001,911 have disclosed a kind of grinding tool, and it has a soft backing and resilient intermediate material layer adheres to the many bonding abrasive particulate material part on the backing by a softness.This bonding material material is embedded on the backing by many, is made up of the separated abrasive material piece in narrow slit each other.

United States Patent (USP) 2,194,472 have disclosed a kind of grinding tool, and it comprises the coating of a backing and abrasive material pellet, and backing is soft, and the abrasive material pellet is porous, polygonal, irregular, is the many single abrasive particle that is bonded them together by a bonding system.In the preparation of this grinding tool, may need this pellet is sieved, so that the pellet particle of the homogeneous granularity that meets the requirements to be provided.

United States Patent (USP) 3,986,847 have disclosed a kind of grinding tool (as emery wheel), and its means of abrasion comprises that abrasive material is mutually bonding with the nature of glass mutually.Abrasive particle mutually or only be CBN, or the combination of the CBN abrasive material material identical with it substantially with a kind of thermal coefficient of expansion.The thermal coefficient of expansion of the bonding phase of the nature of glass is taken charge of mutually with CBN basically.

United States Patent (USP) 4,256,467 have disclosed a kind of flexibility grinding tool, and it comprises the non-conductive mesh material and an electrodeposit metals layer (wherein being embedded with diamond abrasive grain) of a softness, this metal level is adhesion and whole this mesh material that penetrates directly, causes mesh material to be embedded in the metal level.

United States Patent (USP) 4,393,021 discloses a kind of method of producing the granule of abrasive particle.This method is abrasive particle to be mixed with bonding medium and filler form thickener.Thickener is ground into granule again through extruding and heat hardening, contains some abrasive particles in each.

United States Patent (USP) 4,799,939 disclose a kind of grinding tool, and its structure is that many corrodible agglomerate that contain abrasive particle are distributed in the corrodible matrix, and matrix is the hollow bodily form and contains adhesive.Used abrasive particle has aluminium oxide, as the carbide of carborundum, nitride, diamond and flint as CBN.Although preferred the employing synthesized organic bond as adhesive, natural organic bond and inorganic bond also can adopt.The general shape of agglomerate is irregular, but can be made into sphere, elliposoidal, oblate spheroid, particle shape, clavate or other common shapes.

United States Patent (USP) 4,871,376 have disclosed a kind of coated abrasive article, and it comprises a backing, abrasive material and bonding system, and resinoid bond, inorganic filler and coupling agent are arranged in the bonding system.Coupling agent can be selected from silane, titanate and the agent of zircoaluminate connection.

United States Patent (USP) 5,039,311 discloses a kind of grinding tool, and it contains perishable abrasive material granule, granule be will many first kind of abrasive particles to be bonded together by first kind of adhesive to form a kind of perishable basic agglomerate, be coated with second kind of adhesive on every side at it and apply second kind of abrasive particle and bond it.First kind and second kind of adhesive can be the same or different, and can be organic or inorganics, can contain just like various additives such as filler, grinding aid, plasticizer, wetting agent and coupling agents.First kind and second kind of abrasive grain can be the same or different, and can be aluminium oxide, carborundum, diamond, flint, CBN, silicon nitride and combination thereof.The general shape of basis agglomerate is irregular, but can be made into sphere, oblate spheroid, elliposoidal, particle shape, clavate or other common shapes.

United States Patent (USP) 5,152,917 have disclosed a kind of coated abrasive article, and it comprises the backing that has a first type surface at least and many abrasive material complexs on a first type surface at least.Each abrasive particle complex all is that many abrasive particles are dispersed in the adhesive, and this adhesive also plays a part the abrasive material complex is adhered on the backing, and the abrasive material complex has predetermined shape such as pyramid.

United States Patent (USP) 5,210,916 disclose a kind of abrasive grain, its preparation side shows it is that a kind of boehmite sol is poured in the model that many given shape die cavitys are arranged, from colloidal sol, remove the liquid of q.s,, from model, take out these presomas to form the presoma of abrasive grain, calcine, will form abrasive grain through the presoma sintering of calcining again.Die cavity has specific 3D shape, can be triangle, circle, rectangle, square or chamfered edge taper, frustum of a pyramid shape, frusto-spherical, butt spheroid, taper, the taper that falls.

United States Patent (USP) 5,314,513 grinding tools that disclose have a soft backing, by a kind of initially in conjunction with coating or also have one or more other coating at least one deck abrasive grain layer be adhered on the upper surface of backing, wherein at least a coating contains the maleimide amine bonding agent.

United States Patent (USP) 5,318,604 grinding tools that disclose contain the abrasive element that is dispersed in the adhesive base-material.These abrasive element comprise it being the individual particle of abrasives, and their overwhelming majority are partially submerged in the metal-to-metal adhesive.

Contain the abrasive material agglomerate in the coated abrasive article that 1981,4,23 disclosed Deutsche Bundespatent OS 294198-A1 point out, its rough surface is and irregular, and its preparation method is that inorganic abrasive particle is acutely mixed with frit and adhesive; Handle the mixture that is produced; This material of compacting, drying and sintering; Pulverizing generates agglomerate then.

U.S. Serial 08/085638 has disclosed accurate particle of shape and preparation method thereof, contains the organic group adhesive in this particle.The organic group adhesive contains the abrasive particle that is dispersed in wherein.

Although generally be according to its physical property and require the nonferromagnetic substance life-span the strongest and grinding tool to select grinding tool, but need to grind as camshaft and bent axle (as at United States Patent (USP) 4 when industrial, 833, the camshaft belt grinding machine that is disclosed in 834) stiff materials, and service life is during long grinding tool, just need in addition special consideration, at this moment will meet some design accuracies, comprise the parts that accurate grinding can be provided.

Summary of the invention

One embodiment of the invention provide a kind of coated abrasive article, it comprises backing with first first type surface and the abrasive material that is coated on first first type surface, abrasive material has a contact-making surface and a reverse side, contact-making surface is bonded on first first type surface, from the contact-making surface to the reverse side abrasive material thickness, abrasive material contains the bonding system of an organic group and many abrasive material agglomerate that adheres in the bonding system, the basic abrasive particle uniformly of inorganic bond and many sizes and shape is arranged in each agglomerate, on thickness and abrasive material cross section by mid-depth point, total cross-sectional area of its abrasive material agglomerate with by from central point along thickness to 75% some cross section of contact-making surface distance, substantially the same.

In another embodiment, the invention provides a kind of coated abrasive article, it comprises backing with first first type surface and the abrasive material that is coated on first first type surface, abrasive material contains bonding system of an organic group and the many abrasive material agglomerate that are dispersed in the bonding system, a kind of inorganic bond is arranged in each agglomerate and be an abrasive grain that cuts the four sides pyramid.

Also has an embodiment, a kind of coated abrasive article is provided, it comprises backing with first first type surface and the abrasive material that is coated on first first type surface, abrasive material contains bonding system of an organic group and the many abrasive material agglomerate that are dispersed in the bonding system, there are a kind of adhesive and average Knoop hardness number to be at least 70 inorganic filler particle in the bonding system, a kind of inorganic bond and many abrasive particles are arranged in each agglomerate.

The present invention also provides a kind of method of making coated abrasive article, and it comprises that (a) provides a backing with first first type surface; (b) form abrasive material, abrasive material has a contact-making surface and a reverse side, contact-making surface is bonded on first first type surface, from the contact-making surface to the reverse side its thickness, on thickness and abrasive material cross section by mid-depth point, total cross-sectional area of its abrasive material agglomerate with by from central point along thickness to the cross section of 75% point of contact-making surface distance, substantially the same, step (b) comprises that (1) is coated with initially in conjunction with coating (make coat) on first first type surface of backing, this coating contains first kind of organic group binder precursor; (2) provide many abrasive material agglomerate, it (i) contains a kind of inorganic bond and many abrasive particles, and (ii) its size and shape are even basically; (3) agglomerate is dispersed in initially in conjunction with in the coating; (4) allow the effect that initially is subjected to a kind of energy, so that small part is solidified first binder precursor in conjunction with coating; (5) the glued coating of coating on the abrasive material agglomerate has second kind of organic group adhesive in the glued coating; (6) allow glued coating be subjected to the effect of second kind of energy, solidify first kind of binder precursor fully to solidify second kind of binder precursor or also to choose wantonly sometimes.

The invention still further relates to the method that Rockwell " C " hardness is at least 25 hard workpiece of grinding, it comprises that (1) provides a kind of grinding tool that contains backing and abrasive material, contain a bonding system and abrasive material agglomerate in the abrasive material, the inorganic, metal oxide adhesive (b) that has (a) to be substantially free of the free metal in the agglomerate is essentially the abrasive particle of super abrasive grain; (2) under sufficient pressure coated abrasive article being contacted with workpiece grinds workpiece; (3) make coated abrasive article and workpiece do relative motion.

In the past people do not recognize have the coated abrasive article of describing characteristics in the front with and method for making can reach good Grinding Quality.Particularly, coated abrasive article of the present invention can grind hard workpiece effectively.Be to grind with bonding emery wheel to obtain required life-span, grinding speed and workpiece accuracy as the hard workpiece of iron and steel.But bonding grinding tool has been compared two major defects with coated abrasive article.Bonding grinding tool needs to prevent bonding grinding tool passivation, to lose effective grinding speed through surfacing and correction.In addition, bonding grinding tool rigidity is big, lacks flexibility.This rigidity limits its use in some abrasive application.For example, if need grind out a recessed slightly position time, bonding grinding tool just can't satisfy this requirement at the back side of camshaft lobe part.On the contrary, coated abrasive has certain flexibility, can be used for this class abrasive application.Yet the coated abrasive article in past is not long owing to its life-span, and is considered to not be suitable for the grinding hard workpiece.In contrast, coated abrasive article of the present invention then the life-span long, grinding speed and precision are good, and are flexibilities.

The accompanying drawing summary

Fig. 1 cuts the amplification side cross-sectional, view of the coated abrasive article of the abrasive material agglomerate of pyramid on four sides for the present invention has.

The amplification side cross-sectional, view of the coated abrasive article of Fig. 2 cuboidal abrasive material agglomerate and fiber reinforcement backing for the present invention has.

Detailed Description Of The Invention

With reference to figure 1, coated abrasive article 10 of the present invention has comprised backing 11, has initially in conjunction with coating 12 at its first first type surface 18. There are many abrasive material agglomerate 13 to adhere to initially in conjunction with in the coating. Initially be used for the abrasive material agglomerate is adhered to backing in conjunction with coating. Many abrasive particles 14 and inorganic metal oxide binder 15 are arranged in the abrasive material agglomerate. In this embodiment, being shaped as of abrasive material agglomerate cuts the four sides pyramid. It is sizing menting property 16 on the abrasive material agglomerate. An effect of sizing menting property is to strengthen the bonding of abrasive material agglomerate on backing. In this embodiment, initially consist of abrasive material 17 in conjunction with coating, sizing menting property and abrasive material agglomerate.

With reference to figure 2, coated abrasive article 20 of the present invention has comprised backing 21, initially in conjunction with coating 22 cube agglomerate 23 is adhered on the first first type surface 28 of backing. In this embodiment, backing comprises fortifying fibre 29, therefore is the low backing that stretches. Contain many abrasive grains 24 and metal oxide inorganic bond 25 in the abrasive material agglomerate. It is sizing menting property 26 on the abrasive material agglomerate. In this embodiment, initially form abrasive material 27 in conjunction with coating, sizing menting property and abrasive material agglomerate.

The below will describe respectively the every part in the such scheme grinding tool.

Backing

The backing that uses in the grinding tool of the present invention has two first type surfaces at least. The surface that is coated with abrasive material is referred to as the first first type surface. General backing example comprises thin polymer film, primary coat thin polymer film, grey cloth, cloth, paper, vulcanized paper, supatex fabric and through these materials of certain processing and/or their combination.

Also contain some additives in the backing, such as filler, fiber, antistatic additive, lubricant, wetting agent, surfactant, pigment, dyestuff, coupling agent, plasticizer and suspending agent. The consumption of these materials depends on required character. Generally, require backing to have enough intensity and heat resistance, can stand the service condition under the process of lapping. In addition, if grinding tool will use under humidity or lubricating condition, backing should have enough resistances to water and/or oil resistivity, available heat thermosetting resin for this reason, such as phenolic resins (also available modified rubber), epoxy resin (also available a kind of fluorene compound modification), and/or a kind of di maleimide resin processing backing, make backing non-degradable during grinding.

Preferred backing is the cloth backing among the present invention.Cloth is generally by at the i.e. yarn and be that horizontal yarn is formed in broadwise longitudinally of warp-wise.The cloth backing can be woven backing, knitting backing, stitch bonded fabrics backing or weft insertion fabric backing.The example of fabric construction be included in sateen tissue that warp thread on the weft yarn is the four longitudes and one latitude weavy grain, three twill-weaves through a latitude weavy grain, once the plain weave of a latitude weavy grain, two through two latitude weavy grains through face twill-weave.In stitch bonded fabrics or weft insertion fabric backing, warp thread and weft yarn do not interweave, but with different mutually direction orientations.Warp thread is placed on the upper strata of weft yarn, is fixed it by yarn or a kind of binding agent of loop bonding.

Yarn in the cloth backing can be natural, synthetic or its combination.The example of natural yarns comprises as these fibrous materials of cotton, hemp, kapok, flax, sisal hemp, jute, carbon, abaca and combination thereof.The example of synthetic yarn comprises polyester yarn, polypropylene yarn, organdy, polyvinyl alcohol yarn, Nomex (polyaramid) yarn, polyimides yarn, aramid yarn, modrella, nylon gauze, polyethylene yarn and combination thereof.Among the present invention preferably yarn be mixture, modrella and the aramid yarn of polyester yarn, nylon gauze, polyaramid yarn, polyester and cotton.The cloth backing can dyed and stretching, destarch or hot-stretch.In addition, the yarn of cloth backing can contain bottoming agent, dyestuff, pigment or wetting agent, and, can be twisted or Texturized.

Polyester yarn generally is to be formed by a kind of long-chain polymer that the reaction of the ester of dihydroxy alcohol and terephthalic acids produces.Best this polymer is straight chain type poly-(a terephthalic acids ethyl).Three kind polyester yarns are arranged: RING SPINNING, free end spin the yarn with long filament.Ring spinning generally is by the continuous drafting polyester yarn, twisted yarn twines on bobbin then and makes in addition.Open-end-spinning generally is directly to make from sliver or rove, and promptly polyester roving carries out shredding, on a device for spinning all rove being got together forms continuous yarn.Filament yarn generally is long and continuous fiber, compares with polyester fiber, and it only has very low twisted or do not have twisted.

The danier of cloth backing fiber is generally less than 2000, and scope is about 100-1500 preferably.To the cloth backing of coated abrasive article, grey cloth is that the weight of undressed cloth generally is about 0.15-1 kilogram/rice ², be about 0.15-0.75 kilogram/rice preferably ²

The saturated coating of one deck, pre-sizing menting property and/or back side sizing menting property also can be arranged on the backing, be used for backing is sealed and/or protect yarn or fiber in the backing.Add that saturated coating, pre-sizing menting property and/or gum knot coating can also produce smooth surface at the front or the back side of backing.In U.S. Serial No 07/903,360, further described the processing of cloth backing.The material of these coatings generally is the resin binder presoma.Such presoma has phenolic resins, comprises the phenolic resins of modified rubber; Epoxy resin comprises the epoxy resin of fluorenes modification; Amino resin with side group α, β unsaturated carbonyl.After the coating, these binder precursors stand certain energy (generally being heat energy) effect back converted into thermoset adhesive.Also can add inorganic filler in the resin.The example of filler comprises calcium carbonate, clay, silica and dolomite like this.If backing is the cloth backing, these three kinds of coatings are preferably used a kind of at least, and preferably contain a kind of heat-resisting organic resin in this coating.

Behind the saturated coating of coating, back side sizing menting property or pre-sizing menting property on the backing, the backing of gained can be handled (for example heating) and carry out dry at least and/or curing.For example, during heating, the backing that produces is placed on the frame that stretches tight, can be dry and/or cross-linked binder presoma effectively.The employing frame that stretches tight can reduce to shrink to greatest extent, keeps fabric to tighten.In addition, heated after the backing, can make its roller again, carried out calendering by heating.The calendering step helps to make coarse backing surface to become level and smooth.

The preferably low stretching backing of the backing that uses in the grinding tool of the present invention.The low backing that stretches can the life-span divide the use abrasive material with filling more longways and/or.When coated abrasive article contained super abrasive grain, backing is preferably low to stretch, and makes super abrasive grain be able to abundant use.If the draftability of backing is too big, the service behaviour of grinding tool is just not good, for example, if grinding tool is a grinding band that turns round, just can not fully use the super abrasive grain in the agglomerate on driving wheel and/or free pulley.

Term " the low stretching " is with regard to backing is originally under the situation that does not apply bonding system and abrasive material.Adopt the low base material that stretches, then do not stretch, so the life-span of its coating of making grinding belt grinding parts is general longer than the abrasive product made from common substrate because of it can not produce big position on machine." the low stretching " this notion available stretch is tested and is defined, promptly with the stretching phenol number of condition gained of 100 pounds/inch (45 kilograms/2.5 centimetres) (with width of band), the stretch percentages of " the low stretching " material is generally less than 10%, typically less than 5%, preferably less than 2%, better less than 1%.Stretch percentages is preferably less than 0.5%.

Summarizing tension test below, is to carry out tension test before applying bonding system and abrasive material.

Tension test

Backing is vertically made 2.5 * 17.8 centimetres belt along it.Belt is packed into as SystemsIntegration Technology, Inc., Stoughton, the cupping machine of the Sintech machine of Massachusetts, sample in the vertical stretches.Be determined at 100 pounds of stretch percentages under (45 kilograms), it calculates presses following formula:

Original length * 100 of (original length of the sample length-sample after stretching under 100 pounds)/sample

The backing preferably of coated abrasive article of the present invention comprises the lamination band of the satin weave mylar with fortifying fibre.The sliceable endless belt that together forms of mylar.Splicing preferably has two joints that are positioned on the plane, is spliced to form a sinusoidal waveform line, covers one deck above it and strengthens the woven polyester band.It is believed that mylar can provide the good adhesion to the bonding system of organic group and abrasive grain or agglomerate; thereby reducing to peel off is coming off too early of abrasive grain or agglomerate; generally do not wish to come off too early, because can shorten the service life of coated abrasive article.Generally, the heat-resisting lamination binding agent big with intensity comes the lamination fortifying fibre, and mylar contains phenolic aldehyde base impregnating agent and and the glued processing through the back side.The polymerization splicing tape that strengthens is to embed polyester or Nomex enhancing yarn in polyester film, and the thickness of band is generally less than 0.010 inch (0.025 centimetre).

For example, described in U.S. Serial 08/199,835, fortifying fibre or yarn can be laminated to the reverse side of polyester strap, and can be applied to the reverse side of strap in a continuous manner.Generally, the effect of enhancing yarn is to increase the hot strength of backing and reduce its stretching the biglyyest.The example that better strengthens yarn comprises aromatic polyamide fibre, is called aromatic polyamide fibre, polyester yarn, glass fiber, polyamide yarn and the combination thereof of " Kevlar " as the commodity of being produced by E.I.Dupont.The splicing position does not preferably strengthen yarn, makes the enhancing yarn can work to strengthen joint and reduce joint and disconnects.

Bonding system

Bonding system is the bonding system of a kind of organic group, and it is for example a kind of abrasive material slurry or two-layer at least tack coat, and its ground floor is called " initially in conjunction with coating " later on, and the second layer is called " sizing menting property ".The abrasive material slurry comprises the mixture of different abrasive grains, should be very even.

Generally form initially in conjunction with coating and sizing menting property by organic group binder precursor such as resin.Being used to form initially can be identical or different with the presoma that forms sizing menting property in conjunction with the presoma of coating.Stand the effect of the appropriate condition such as the suitable energy, it is adhesive that resin forms crosslinked thermosetting polymer with regard to polymerization.The example of ordinary resin binding agent comprises phenolic resins, side group α is arranged, amino resin of β unsaturated carbonyl, polyurethane resin, epoxy resin, olefinic unsaturated-resin, propylene acidifying isonitrile urea acid ester resin, urea formaldehyde resin, isonitrile urea acid ester resin, propylene acidifying polyurethane resin, propylene acidifying epoxy resin, di maleimide resin, fluorenes modified epoxy and composition thereof.Epoxy resin and phenolic resins are preferable.

Because its good in thermal property, cost is higher and be easy to obtain and handle, phenolic resins is widely used as binder precursor.Two types phenolic resins is arranged, bakelite and novolac resin.The formaldehyde of bakelite and phenol mol ratio are generally more than or equal to 1: 1, and general range is 1.5: 1-3: 1.The formaldehyde of novolac resin and the mol ratio of phenol are generally less than 1: 1.The phenolic resins of market sale has the product of the Occidental chemical company of commodity " Durez " and " Varcum " by name; The product of the Monsanto of commodity " Resinox " by name; The product of the Ashland chemical company of commodity " Arofene " and " Arotap " by name.

Generally have a side group α, β unsaturated carbonyl in each molecule of amino resin or the oligomer at least.Spendable amino resin, as at United States Patent (USP) 4,903,440 and 5,236,472 described these resinoids.

Epoxy resin has an oxirane ring, can the polymerization by opening this ring.Suitable epoxy resin comprises cyclosiloxane monomer epoxy resins and poly epoxy resin, and it can have different main chains and substituting group.Generally, main chain can be the main chain of any kind and epoxy resin connection, and as bisphenol-A, substituting group can comprise the group of any non-activity hydrogen atom that can react at room temperature and oxirane ring.The representative example of suitable substituent has halogen, ester group, ether, sulfonic group, siloxy group, nitro and phosphate.

The example of epoxy resin has 2 preferably, 2-is two, and [4-(2, the 3-glycidoxy)-and phenyl] product of commodity " Epon 828 ", " Epon 1004 " and " Epon1001F " by name of propane (diglycidyl ether of bis-phenol) and shell chemical company, the product of Dow chemical company is called the product of " DER-331 ", " DER-332 " and " DER-334 ".Other suitable epoxy resin comprise the glycerin ether of novolac resin, are called the product of " DEN-431 " and " DDEN-428 " as the commodity of Dow chemical company.

The olefinic unsaturated-resin comprises and contains carbon, hydrogen, oxygen, monomer and compound aggretion type of also nitrogenous sometimes and halogen atom.Generally in ether, ester, polyurethane, acid amides and urea groups, exist oxygen or nitrogen or two kinds all to exist.Alefinically unsaturated compounds preferably its molecular weight preferably contains aliphatic monohydroxy or aliphatic series polyol and unsaturated carboxylic acid less than about 4000, the ester that forms as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, iso-crotonic acid and maleic acid reaction.

The representative example of acrylate comprises methyl methacrylate, EMA styrene, divinylbenzene, vinyltoluene, glycol diacrylate, glycolmethacrylate, hexanediyl ester, triethylene-glycol diacrylate, TMPTA, glycerol tri-acrylate, pentaerythritol triacrylate, pentaerythrite methacrylate, tetramethylol methane tetraacrylate.

Other olefinic unsaturated-resins comprise monoene propyl group, polyenoid propyl group and many methacrylic esters and carboxylic acid amide, as diallyl phthalate, diallyl adipate and N, N-diallyadkipamide.Other suitable nitrogen-containing compounds comprise isonitrile urea acid three (2-methacryl-oxygen ethyl) ester, 1,3,5-three (2-the methylacryoyloxyethyl)-second month in a season-triazine, acrylamide, Methacrylamide, N methacrylamide, N,N-DMAA, N-vinyl pyrrolidone and N-vinyl piperidones.

Propylene acidifying polyurethane is that hydroxyl stops the polyester of NCO elongation or the ester of polyethers.Propylene acidifying polyurethane commodity have the product of the commodity of Morton Thiokol Chemical by name " Uvithane 782 " and the commodity " CMD 6600 " by name of RadcureSpecialities, the product of " CMD 8400 " and " CMD 8805 ".

Propylene acidifying epoxy resin is the diacrylate of epoxy resin, as the diacrylate of bisphenol A epoxide resin.This class propylene acidifying epoxy resin has the commodity " CMD3500 " by name of Radcure Specialties, the product of " CMD 3600 " and " CMD 3700 ".

Bonding system of the present invention, for example initially in conjunction with coating and/or sizing menting property, also can contain some additives, as filler (comprising grinding aid), fiber, antistatic additive, lubricant, wetting agent, surfactant, pigment, dyestuff, coupling agent, plasticizer and suspending agent.Can select the amount of these materials according to the performance that need provide.

The example of the filler that uses among the present invention comprises metal carbonate (as calcium carbonate (as chalk, calcite, marl, calcareous tufa, marble and lime stone), miemite, sodium carbonate and magnesium carbonate); Silica (quartz, bead, glass envelope, glass fibre); Silicate (as talcum, clay (if you would take off stone), feldspar, mica, calcium silicates, calcium metasilicate, sodium silicoaluminate, sodium metasilicate); Metal sulfate (as calcium sulfate, barium sulfate, sodium sulphate, aluminum sodium sulfate, aluminum sulfate); Gypsum; Vermiculite; Wood powder; Aluminum trihydrate; Carbon black; Metal oxide (as calcium oxide (lime), aluminium oxide, titanium dioxide); Metal sulphite (calcium sulfite).The mean particle size range of filler is generally the 0.1-100 micron, is the 1-50 micron preferably, better is the 1-25 micron.

Suitable grinding aid is some specific materials, and its interpolation can produce the obvious and effective improvement to the chemistry and the physical process of grinding.Specifically, grinding aid possibility 1) friction of minimizing abrasive grain and polished parts, 2) prevent " capping " phenomenon (being the top that metallic particles is welded on abrasive grain) 3 of abrasive grain) reduce abrasive grain with by the interface temperature of grinding component, and/or 4) reduce abrasive power.The adding grinding aid generally can increase the life-span of coated abrasive article.Grinding aid has various material, can be inorganic based, also can be organic group.

The example of grinding aid comprises wax, organohalogen compounds, haloid and metal and alloy thereof.Organohalogen compounds generally can decompose when grinding, and discharge hydracid or gaseous halide.Such material comprises chlorinated wax class and the polyvinyl chloride as Tetrachloronaphthalene, Pentachloronaphthalene.The example of haloid comprises sodium chloride, elpasolite, sodium cryolite, ammonium ice crystal, potassium tetrafluoroborate, sodium tetrafluoroborate, silicon fluoride, potassium chloride, magnesium chloride.The example of metal has tin, lead, bismuth, cobalt, antimony, cadmium, iron and titanium.Other grinding aids comprise Sulfur, organosulfur compound, graphite and metal sulfide, also comprise the combination of different grinding aids, for example, have described the combination of potassium tetrafluoroborate and halogen polymer among the U.S. Serial 08/213,541.The example of above-mentioned grinding aid only is the representative illustration to grinding aid, does not mean to have comprised all grinding aids.

The example of antistatic additive has graphite, carbon black, vanadium oxide, wetting agent etc.United States Patent (USP) 5,061,294; These antistatic additive have been disclosed in 5,137,542 and 5,203,884.

Measure according to ASTM E384-89, bonding system of the present invention, to bear abrasive power and can't be pulverized in conjunction with coating and sizing menting property as initially, and its Knoop hardness number (KHN) generally is at least 50KHN (also can use kilogram/millimeter ²(kgf/mm ²) expression), typically be at least 60KHN, be at least 70KHN preferably, better be at least 80KHN, preferably be at least 90KHN.

Generally, if bonding system is initially in conjunction with coating and sizing menting property, initially in conjunction with having at least one deck should comprise about 5-95 weight portion in coating and the sizing menting property, be preferably a kind of binder precursor of 30-70 weight portion as thermosetting resin, with the 5-95 weight portion, be preferably the filler of 30-70 weight portion.If bonding system is a kind of abrasive material slurry, the amount of binder precursor and filler in abrasive material slurry weight, is respectively 5-95 weight %.

For example, under above-mentioned filler particles existence condition, can obtain to have the bonding system of better Knoop hardness number scope, promptly Knoop hardness number is at least 70KHN preferably, better is at least 80KHN, the best 90KHN that is at least.Filler particles can make the hardening of resin after the curing, and makes bonding system begin as before to increase in conjunction with the toughness of coating and sizing menting property.The amount of filler particles and coupling agent have a Knoop hardness that helps control bonding system.

Obtain Knoop hardness scope preferably, in filler and/or abrasive grain, coupling agent can be arranged.Coupling agent provides the bridge that is connected between bonding system and filler and/or the abrasive grain.The example of suitable coupling agent has organosilan, zircoaluminate and titanate.The amount of coupling agent in the total amount of filler and abrasive material agglomerate, is about 0.1-5 weight %.

As above-mentioned, filler is preferably use-case such as organic silane coupling agent carries out preliminary treatment.The product of the commodity that this class coupling agent is Union Carbide " A-1100 " by name, calcium metasilicate filler particles and alumina packing particle are more preferably with silane coupling agent to be handled.Also can in the compound of resin and filler, add coupling agent.Can use several filler particles, calcium metasilicate then preferably uses separately.Handle the bonding that to improve bonding system and abrasive grain with coupling agent.In addition, the existence of coupling agent can improve the rheological property of binder precursor (for example bakelite and calcium metasilicate filler particles).

Specifically, in order to obtain the Knoop hardness number of 70KHN at least, the filler that bonding system preferably contains and the amount of coupling agent in the weight of bonding system, are respectively 50-90 weight portion and 0.2-50 weight portion.For example, initially in conjunction with in coating and/or the sizing menting property, in conjunction with coating and/or sizing menting property weight, contain the crosslinked bakelite of 35 weight portions and the calcium metasilicate and the alumina packing particle of 65 weight portions in initially, this filler has used the coupling agent of 0.5 weight portion pretreated.If use multiple filler particles, for example calcium metasilicate and alumina packing particle, its mean particle size range is the 0.2-50 micron, is the 1-25 micron preferably, better is the 2-10 micron.

The periphery coating

Bonding system can comprise a periphery coating.For example, if bonding system comprises that initially in conjunction with coating and sizing menting property, the periphery coating that is also referred to as sizing menting property can be coated on the sizing menting property, or is coated on the abrasive material slurry.The periphery coating can be formed by organic group binder precursor (for example initially in conjunction with the resin described in coating and the sizing menting property), contains a kind of grinding aid in the periphery coating.Suitable grinding aid comprises the grinding aid of previously described bonding system.For example, the periphery coating can contain the tetrafluoro boric acid k particle that is dispersed in the crosslinked epoxy resin.General roller coat or the spraying method coating periphery coating on sizing menting property that solidifies or slurry that adopts, the periphery coating is to separate to solidify with sizing menting property/abrasive material slurry.

Abrasive grain

The abrasive grain that coated abrasive article of the present invention uses comprises by inorganic bond many abrasive particles being bonded together becomes the agglomerate of separating the shape material.The abrasive particle that disperses in abrasive material agglomerate and the grinding tool is different, because it is made up of many abrasive particles, so the life-span of growing can be provided.In use, wearing and tearing and can from the abrasive material agglomerate, peel off away the abrasive particle that exposure makes new advances with the abrasive particle of crossing.

General its mean particle size range of spendable abrasive material agglomerate is about the 20-3000 micron, is the 50-2000 micron preferably, better is the 200-1500 micron.

Each abrasive material agglomerate all contains a kind of inorganic bond and many abrasive particles.The example of suitable abrasive particle comprises by fused alumina, ceramic alumina, heat treatment aluminium oxide, carborundum, zirconia oxidation aluminium (aluminazirconia), ceria, garnet, carbon boron nitride, B ₆O and B ₁₀The boron oxide of O form, diamond, CBN and the abrasive grain that constitutes thereof.In United States Patent (USP) 4,314,827; 4,770,671; 4,774,802; 4,881,951; 5,011,508; 5,139,978; 5,164,348; Disclosed the example of ceramic alumina in 5,201,916 and 5,213,591.

Abrasive particle is " super abrasive grain " or be " super abrasive grain " basically preferably.The hardness of " super abrasive grain " generally is at least about 35GPa, is at least 40GPa preferably, as diamond, CBN and combination thereof.Abrasive particle is CBN preferably.Here the term that is used to illustrate super abrasive grain " be basically " be meant at least 30%, preferably 50%, better 70% to 100% abrasive particle is super abrasive grain.

Super abrasive grain is extremely effective when grinding stone workpiece such as hardened steel, pottery, cast iron and rock material.Can obtain super abrasive grain diamond and CBN from many companies, as general electronic corporation, American Boarts company and DeBeers.Diamond can be natural, also can synthesize.CBN is synthetic preparation, can obtain with the trade name of " Borazon " from General Electric.The various types of diamonds and the CBN that have quality to have nothing in common with each other.Its hardness, toughness, be polycrystalline or monocrystalline, be that the shape of natural or synthetic, abrasive particle all can be different.

The particle size range of abrasive particle generally is about the 0.1-1500 micron, is the 1-1300 micron preferably.Generally by the granularity of required grinding speed with the surface smoothness decision abrasive particle of wanting coated abrasive article to produce.Because agglomerate comprised many abrasive particles, the granularity of the abrasive particle in a given agglomerate makes coalescent physical efficiency comprise many abrasive grains widely less than the granularity of agglomerate.

Above the abrasive particle of the present invention a kind of face coat can also be arranged.The known surface coating can be improved in the agglomerate between the abrasive particle and adhesive, the caking property between agglomerate and the bonding system, so can improve the abrasive characteristic of abrasive particle/agglomerate.Suitable face coat is included in United States Patent (USP) 1,910,444; 3,041,156; 5,009,675; 4,997,461; 5,011,508; 5,213,591 and 5,042, described in 991.For example, diamond and/or CBN can contain the face coat just like metal or metal oxide, thereby improve the caking property of inorganic bond in itself and the agglomerate.In addition, for example on abrasive particle, can there be very thin nickel dam.

The example of inorganic bond comprises inorganic, metal oxide, as vitrified bond, glass ceramics adhesive and ceramic binder.Be preferably in the adhesive of inorganic, metal oxide and do not have the free metal basically." there is not the free metal basically " and refers to the free metal that in the inorganic, metal oxide adhesive, exists, in the gross weight of inorganic, metal oxide adhesive, generally be not more than approximately 1%, be not more than 0.5% preferably, better be not more than 0.25%, even be 0%.

The example of inorganic, metal oxide comprises silica, silicate, aluminium oxide, sodium oxide molybdena, calcium oxide, potassium oxide, titanium oxide, iron oxide, zinc oxide, lithia, magnesia, boron oxide, lithium aluminium silicate, borosilicate glass and combination thereof.Lithium aluminium silicate and borosilicate glass are more suitable.The preparation of inorganic bond is that the metal oxide mixture through grinding melts, and cooling forms solid glass; Then glass is worn into very thin powder.

The thermal coefficient of expansion of inorganic bond preferably equals or is substantially equal to the thermal coefficient of expansion of abrasive grain.When the thermal coefficient of expansion of inorganic bond equals or is substantially equal to the thermal coefficient of expansion of abrasive grain, when preparation abrasive material agglomerate (as in its vitrifying process), the contraction of abrasive particle and inorganic bond is just more even, on the interface of inorganic bond/abrasive particle, only produce very little internal stress, thereby avoid any early stage fragmentation of agglomerate.

Refer to here between the thermal coefficient of expansion of the thermal coefficient of expansion of adhesive and abrasive grain that " basically " its difference generally should be less than about 80%, preferably less than about 50%, better less than 30%.More preferably when inorganic bond is the vitrifying adhesive, especially should be for this reason.

For example, the thermal coefficient of expansion of CBN is about 3.5 * 10 ^-5/ ℃.Suitable vitrified bond, the difference of the thermal coefficient of expansion of its thermal coefficient of expansion and CBN should promptly should be about 2.8 * 10 less than about 80% ^-6/ ℃-4.4 * 10 ^-6/ ℃.

Contain in the vitrifying agglomerate of abrasive particle and vitrified bond in preparation, before its vitrifying, preferably that adhesive is levigate to passing through 325 purpose sieves.For example, one preferably vitrified bond contain 51.5 weight % silica, 27.0 weight % boron oxides, 8.7 weight % aluminium oxide, 7.5 weight % magnesia, 2.0 weight % zinc oxide, 1.1 weight % calcium oxide, 1.0 weight % sodium oxide molybdenas, 1.0 weight % potassium oxides and 0.5 weight % lithia.The interpolation boron oxide can improve the bonding to the CBN abrasive particle.

Each agglomerate in the weight of agglomerate, contains inorganic bond and generally is about 10-80%, better is about 20-60%, and abrasive particle generally is about 20-90%, better is about 40-80%.

The abrasive material agglomerate also can contain other additives, as filler, grinding aid, pigment, tackifier and other processing materials.

The example of filler comprises little glass envelope, solid glass ball, aluminium oxide, zirconia and the metal oxide filler that can improve the agglomerate corrosion resistance.The example of grinding aid comprises previously discussed.The example of pigment comprises iron oxide, titanium dioxide and carbon black.The example that the processing material is promptly handled auxiliary agent comprises liquid and temporary organic bond presoma.Liquid can be water, organic solvent and combination thereof.Representative examples of organic comprises alkanes, as the alcohols of isopropyl alcohol, ketone, ester class and ethers as methyl ethyl ketone.

Be used to form the temporary organic bond presoma of easy-to-handle even fluidity mixture, comprise thermoplasticity and thermosetting resin, as wax, polyamide, mylar, phenolic resins, acrylate, epoxy resin, polyurethane resin and urea-formaldehyde resins.According to the chemical characteristic of selected inorganic bond, also curing agent or crosslinking agent can be arranged together with temporary organic bond presoma.Temporary organic bond helps the moulding of abrasive material agglomerate.In the vitrifying process, temporary organic bond decomposes, thereby stays the space in the abrasive material agglomerate.

The abrasive material agglomerate preferably contains the coating of inorganic particle.This coating can increase surface area, improves the bonding between bonding system and the abrasive material agglomerate.The example of the inorganic particle of coating agglomerate comprises filler and abrasive particle, for example, metal carbonate, silica, silicate, metal sulfate, metal carbides, metal nitride, metal boride, gypsum, metal oxide, graphite and metal sulphite.Preferably inorganic particle with abrasive particle, better be exactly with the abrasive material agglomerate in the identical abrasive particle of abrasive particle.Can also from abrasive particle previously discussed, select the particle that is used to be coated with.The granularity of inorganic particle can be identical with the granularity of abrasive particle in the abrasive material agglomerate, or also can be greater than or less than the granularity of abrasive particle.The particle size range of inorganic particle is about the 10-500 micron preferably, better is the 25-250 micron.

Can seal the abrasive material agglomerate with the coating of organic or inorganic.Therefore, bonding system (as initially in conjunction with coating and sizing menting property) has only seldom porous in the abrasive material agglomerate of sealing.

In one embodiment, each agglomerate contains a kind of inorganic bond and many abrasive particles, and the shape of these agglomerate and size are substantially the same.When size that refers to agglomerate and shape, " substantially the same " is meant that the difference between agglomerate size and shape is not more than 50%, better is not more than 40%, better is not more than 30%, preferably is not more than 20%.

Each agglomerate comprises a kind of inorganic bond and many abrasive particles, and its shape is preferably cuts four sides pyramid or cube.

Abrasive material

As described above, abrasive material contains the agglomerate of the bonding system of a kind of organic group and many abrasive materials.Be coated on the abrasive material on first first type surface of backing, a face (" contact " face) and a reverse side that is bonded to this first first type surface is arranged.Be " thickness " of abrasive material from the contact-making surface to the reverse side, press the minimum range definition between contact-making surface and the reverse side.

In one embodiment, on thickness and the abrasive material cross section by mid-depth point, wherein total cross-sectional area of abrasive material agglomerate is basically with identical by the gross area of the abrasive material agglomerate to the cross section of (calculating " from central point to the contact-making surface distance 75% " from the central point to the contact-making surface) some position of 75% of contact-making surface distance from central point along thickness." abrasive material agglomerate cross section " is meant the amount of the abrasive material agglomerate that can be used for contact workpiece on the cross section of abrasive material.When referring to total cross-sectional area of agglomerate, " basically " the total cross-sectional area that is meant the abrasive material agglomerate by mid-depth point with by 75% point from the abrasive material central point to the contact-making surface distance area discrepancy be not more than 40%, better be not more than 30%, better be not more than 20%, preferably be not more than 10%.

Finishing and finishing

Grinding tool is repaired and finishing it before being preferably in and being used for grinding, and also carries out it at the grinding tempus intercalare.Reconditioning is to remove adhesive and the process of grinding the gap is provided from the abrasive dust particle.Finishing is that the leveling lapped face is to improve the process of grinding tolerance.Can be by finishing and the finishing of carrying out coated abrasive of the present invention described in the WO 93/02837.For example can use width to be substantially equal to the backing width of the coated abrasive article of need finishing at least, the multiple spot grinding tool that the material of its grinding skin is harder than abrasive particle is repaired, grind off the boss on the grinding tool particle, to form the copline surface that generally is parallel to backing back of the body surface.This grinding tool surface is to be made of diamond, boron nitride or other suitable removing materials harder than abrasive particle.With compare with the single-point grinding tool, can reduce the required time with multiple spot grinding tool finishing coated abrasive article.If suitable, the grinding skin of grinding tool can be placed on the polished workpiece by any spacing.

The method for preparing the abrasive material agglomerate

The method for preparing the abrasive material agglomerate used in the present invention for example is to mix inorganic bond presoma, abrasive particle and temporary these raw materials of organic bond presoma.Temporary organic bond presoma makes mixture be easy to moulding, and is further keeping this shape in the processing.Also can use other above-mentioned additives and handle auxiliary agent, as inorganic filler, grinding aid and/or liquid medium.

Employing can form any technology of homogeneous mixture and mix these raw materials.Be preferably in as abundant compound abrasive particle and temporary organic bond in the mechanical mixture device of epicyclic mixer, in the gained mixture, add the inorganic bond presoma then, mix again, generally take 10-30 minute up to obtaining homogeneous mixture.

To this mixture, form and be processed to form the agglomerate presoma.Shaping can be adopted mold pressing, extruding and method for die cutting.Owing to lose temporary organic bond presoma and inorganic bond presoma, generally can produce some contractions, when decision initial shape and size, should be taken into account this contraction.Available batch (-type) or continous way form.The technology of a preferred shaping abrasive material agglomerate is to put into a soft mold with mixing the raw material that forms homogeneous mixture.For example, if form the abrasive material agglomerate of cutting the four sides pyramidal shape, mould can be made this shape.Soft mode can be any mould that is easy to take out agglomerate, as organic silicon mould.In addition, can contain releasing agent in the mould and help the demoulding.The mould of mixture of will having packed into places baking oven, and heating is to remove partially liq at least.Heating-up temperature depends on temporary organic bond presoma, is generally 35-200 ℃, is 70-150 ℃ preferably.From mould, take out warp then to the small part dried mixture.For taking out agglomerate, also mould can be damaged fully is burning-off.

As mentioned above, the coating of one deck inorganic particle is arranged preferably on the abrasive material agglomerate, increase surface area and reduce when grinding tool is made these abrasive material agglomerate gathering each other.Obtaining a method of this coating, is after promptly taking out from mould after the agglomerate presoma is shaped, it to be mixed with inorganic particle.Also can add a spot of water and/or solvent or temporary organic bond presoma, so that inorganic particle is anchored on the surface of abrasive material agglomerate presoma, their amount is 5-15 weight % in agglomerate presoma weight, is preferably 6-12 weight %.

Heat the agglomerate presoma then, burning-off is used to prepare the organic material (as temporary organic bond) of agglomerate presoma, and makes inorganic bond fusing or vitrifying, and this can separately carry out or carry out continuously under suitable temperature required variation.Answer the temperature of selective combustion organic material, avoid producing the hole that should not have in the abrasive material agglomerate, this temperature depends on that generally the component that may add comprises the chemical property of temporary organic bond presoma.Though can burn under higher temperature, the temperature range of burning organic material generally is about 50-600 ℃, is preferably 75-500 ℃.Make inorganic bond fusing and vitrified temperature range generally be about 650-1150 ℃, be preferably 650-950 ℃.

Then the agglomerate that obtains is heat-treated, purpose is to optimize its bond properties.Heat-treatment temperature range is 300-900 ℃, is preferably 350-800 ℃, more preferably 400-700 ℃.

Make the method for coated abrasive article

What describe below is a kind of method of suitable but not exclusive manufacturing coated abrasive article.This suitable used binding of method is initially in conjunction with coating and sizing menting property, and all backings have first first type surface.Yet this method also can be coated on the abrasive material slurry earlier on first first type surface of backing, (contain many abrasive material agglomerate and a kind of binder precursor in the abrasive material slurry, describe in front), handle it then under certain condition, binder precursor is solidified and the formation abrasive material.The condition of handling comprises heating, as below initially in conjunction with as described in the curing of coating and sizing menting property.

If what use is low stretching backing, this backing can prepare by the method described in U.S. Serial 08/199,835 or the WO 93/12911.For example, layer of material such as scrim, common cotton or polyester backing or supatex fabric being wound on a supporting construction (as cylinder) goes up and prepares a kind of backing of enhancing as basic unit.This basic unit can comprise several layer coiled materials, or only is one deck, also can be the method splicing with common butt joint or overlap joint.A kind of liquid organic polymer adhesive of coating in this basic unit is therein again around going into fibre reinforced materials.Fibrous reinforcements can be the form of many single cordage, fibrous braid or its combinations.The characteristic of the final this backing strip that obtains depends on the type of selected fibre reinforced materials, for example glass fiber, polyester yarn or aramid fiber.The most handy organic polymer adhesive material of fibre reinforced materials soaks into.Then, adopt any existing method on this seamless jointless backing, to be coated with abrasive coating.In addition, the backing that can use any common coated abrasive article to use.

Can adopt that any suitable technology such as spraying, roller coat, mould are coated with, powder is coated with, hot melt is coated with or method such as blade coating, will contain the initial of the first organic group binder precursor and be applied on first first type surface of backing in conjunction with coating.To throw by the abrasive material agglomerate of top described preparation again and spread and adhere to this initially in conjunction with promptly being dispersed in the coating precursor initially in conjunction with in the coating precursor.Generally be that abrasive material agglomerate spot printing is got on, preferably can form individual layer.Initially the thickness in conjunction with coating should be able to bury one deck abrasive material agglomerate, and its another layer of adhering.In addition, agglomerate should evenly distribute.For obtain to have abrasive material perpendicular to thickness and the cross section by mid-depth point (total cross-sectional area of its abrasive material agglomerate with by from central point along thickness to 75% some cross section of contact-making surface distance; substantially the same); with size and shape basically uniformly the abrasive grain confusion be applied to initially in conjunction with in the coating, small difference is on average fallen.

The member that can obtain is accepted the effect as first energy of heating, ultraviolet light or electron beam, make that the partly solidified at least formation of first binder precursor can not flow initially in conjunction with coating.For example, at 50-130 ℃, 80-110 ℃ of heat treated is 30 minutes-3 hours more fortunately with the member that obtains.Then, by as any common process such as spraying, roller coat or curtain coatings, will contain with the identical or different second organic group binder precursor of the first organic group binder precursor and be coated on the abrasive material agglomerate.Make the abrasive component of gained accept the effect as second energy of heating, ultraviolet light and electron beam identical or different at last, make initially in conjunction with coating and second binder precursor solidifies fully or polymerization becomes thermosetting polymer with first energy.

By top described, can prepare the coated abrasive article that Knoop hardness is at least the bonding system of 70KHN, different is that the filler particles that uses in first and second binder precursors is the calcium metasilicate that is used in combination with the silanes coupling agent.

Use the method for coated abrasive article

Can use the grinding tool grinding work-piece.Workpiece material can be as metal, alloy, exotic alloys, pottery, glass, timber, like the material of any kind of wooden class material, composite, painted surface, plastics, reinforced plastics, rock material and combination thereof.Workpiece can be flat or different shape is arranged.The example of workpiece has glass, plastic lens, tv glass screen, metal Automation Elements, plastic components, particieboard, camshaft, bent axle, furniture, the turbine blade of glass, the Plastic eyeglasses of glass glasses, the Automation Elements and the magnetic medium of paint.

In the process of lapping, abrasive product moves with respect to workpiece, and is perhaps opposite, and grinding tool is ground workpiece.According to application, the power of grinding on the interface is about the 0.1-1000 kilogram, looks the application scenario and different.Be the 1-500 kilogram generally in the power of grinding on the interface.In addition, can under moistening condition, grind.Wet condition comprises water and/or liquid organic compound.Liquid organic compound commonly used comprises organic compound, lapping liquid and the liquid soap of lubricant, oil, emulsification.These liquid also can contain other additive, as defoamer, degreasing agent and corrosion inhibitor.During grinding, grinding tool can carry out oscillating movement on the grinding interface, produces more smooth surface on polished parts.

Grinding tool of the present invention can manually use or be contained in as use on the resinder.Grinding tool can be made as abrasive band, abrasive band roller, mill or abrasive disc.

Grinding belt is used, and is that the two ends with abrasive disc are joined together to form the endless belt.Also can use the endless belt described in the WO 93/12911.Generally, annular grinding belt can be pressed nog plate or contact wheel with one and be rotated around at least one dummy roll.Regulate the hardness of pressuring template or contact wheel, to obtain the surface smoothness of required grinding speed and workpiece.The speed of grinding belt depends on desired grinding speed and surface smoothness, generally is about 20-100 surface meter per second, is typically 30-70 surface meter per second.The magnitude range of band widely is about 0.5-100 centimetre, is preferably 1.0-30 centimetre, is about to be 5-1000 centimetre, is preferably 50-500 centimetre.

Grinding belt can be the grinding tool of continuous length, and its width is about 1-1,000 millimeter, is preferably the 5-250 millimeter.This grinding belt generally not around getting up to use, is placed on the supporting pad, and this supporting pad is pressed on grinding belt on the workpiece, reels then.Grinding belt can infeed abrasive material interface and dislocation continuously.

Mill can be included in the grinding tool field be called " chrysanthemum shape " shape mill, its diameter is about 50-1,000 millimeter, is preferably the 50-100 millimeter.The general mat of mill one bindiny mechanism is fixed on the supporting pad, with 100-20, and 000 rev/min, be generally 1,000-15,000 rev/min is rotated.

Coated abrasive article of the present invention can grind rockwell's hardness " C " especially effectively and be at least about 25, typically is at least about 35, preferably at least about is 45, better is at least about 50 hard workpiece.Such workpiece material comprises steel and cast iron.When coated abrasive article of the present invention with before workpiece contacts by preceding described through after the finishing, effective especially to the hard precise finiss of hard workpiece.In the life span of grinding tool, when it can not satisfy desired performance, for example in the time can not satisfying the requiring of surface smoothness and/or grinding precision, just it is carried out finishing.

Measure hardness according to ASTM Standard Number A370-90.The example of hardened steel and cast iron member comprises camshaft, bent axle, engine components, bearing surface, and the machine part that must be able to stand serious or medium abrasive conditions in long-time.Abrasive method comprises provides coated abrasive article of the present invention earlier, and coated abrasive article is contacted with hard workpiece, makes coated abrasive article be moved by grinding component relatively.Can be in the presence of current or lubricant grinding work-piece.At one preferably in the embodiment, coated abrasive article comprises a backing and abrasive material, and a bonding system and many abrasive material agglomerate are arranged in its abrasive material, and a kind of vitrifying adhesive and many superabrasive abrasive particles are arranged in the agglomerate.

A suitable purposes of the present invention is that available grinding tool of the present invention grinds as United States Patent (USP) 4,833, the camshaft of description in 834.

Embodiment

Following non-limiting example can further specify the present invention.Unless otherwise indicated, all parts, percentage among the embodiment, compare etc. and to be weight portion, percetage by weight, weight ratio.Abbreviation below use the back:

The DIW deionized water;

EP1 epoxy resin, shell chemical company (Houston, the product of commodity TX) " Epon 828 " by name;

The EPH1 epoxy curing agent, Henkel company (Minneapoils, the product of commodity MN) " Versamid125 " by name;

EP2 epoxy resin, the product of the commodity of shell chemical company (Houston TX) " Epon 871 " by name;

The EPH2 epoxy curing agent, Henkel Polymers Division (LaGrange, the product of commodity IL) " Genamid 747 " by name;

The PR bakelite contains 0.75-1.04% free formaldehyde and 6-8% free-phenol, and percent solids is about 78%, and all the other are water, and pH is about 8.5, and viscosity is about the 2400-2800 centipoise;

The SCA silane coupling agent, the product of the commodity of Union Carbide " A-1100 " by name

PH2 2-benzyl-2-N, N-dimethylamino-1-(4-morpholino phenyl)-1-butanone, Ciba Geigy company (Hawthorne, the product of commodity NY) " Irgacure 369 " by name;

The SWA1 wetting agent, Akzo Chemie America (Chicago, the product of commodity IL) " Interwet33 " by name;

The SWA2 wetting agent, the product of the commodity of Union Carbide company " SIlwetL-7604 " by name;

The SAG1 cubic boron nitride has 60% nickel coating layer, is General Electric (Worthington, OH) product of commodity " CBN II " by name;

The SAG1 cubic boron nitride is General Electric (Worthington, OH) product of commodity " CBNI " by name;

The AO alumina abrasive grain;

The MDA methylene dianiline, BASF AG (Parsippany, NJ) product;

The MAA methacrylic acid, Rohm and Haas (Philadelphia, product PA);

PMA polypropylene glycol methyl ether acetate;

The UPR polyether polyols with reduced unsaturation, Uniroyal chemistry Co., Ltd (Middlebury, the product of commodity CT) " Adiprene BL-16 " by name;

PEG4D PEG400 diacrylate, Sartomer Co., Ltd (Exton, product PA);

UAO urethanes acrylate, Morton International (Chicago, the product of commodity IL) " Uvithane 893 " by name;

The AC amine hardener, Albemarle company (Baton Rouge, the product of commodity LA) " Ethacure100 " by name;

The EGME ethylene glycol monobutyl ether (EGMBE) also claims polysolve, Olin company (Stmford, product CT);

The PS100 hydrocarbon solvent, Exxon chemical company (Houston, the product of commodity TX) " WC-100 " and " Aromatic 100 " by name;

The CMST calcium metasilicate, NYCO (Willsboro, the product of trade name NY) " 325 Wollastonite ";

The CMSK calcium metasilicate, NYCO (Willsboro, the product of trade name NY) " 400 Wollastonite ";

The ASF2 silica filler, the product of the commodity of DeGussa GMBH (Germany) " Aerosil R-972 " by name;

The ASC clay, Engelhad company (Edison, the product of commodity NJ) " ASP 600 " by name.

In Comparative examples A and B and embodiment 1-6, made the coating grinding belt:

Comparative examples A

The used backing of Comparative examples A is polyester backing (360 gram/rice ²), it has been coated with pre-sizing menting property with 60 parts of EP1/40 part EPH1 and has been coated with back side sizing menting property with 50 parts of EP1/50 part EPH1 resins that added calcium carbonate and bronze powder again.The abrasive material slurry of the listed prescription of table 1 is coated on this backing with doctor knife coater, and this belt of gained solidified 90 minutes at 90 ℃ then cold curing 10 minutes, solidified 14 hours at 113 ℃.Made the endless belt of long 132 inches (335.3 centimetres) with common opposite joint joining method.When splicing, the back side sizing menting property that is added with bronze powder is scraped off, in order to avoid produce difference in thickness at the splicing position.It is wide that belt is cut into 15/16 inch (2.38 centimetres).

Table 1-abrasive material slurry

Component	Amount
		????DIW	????12.7
????ASC	????3.5
		????PR	????33.3
????ASF2	????0.8
		????SWA1	????0.2
????SAG1(74MIcron)	????49.5

Model at Litton Landis Industries is this grinding belt of test Comparative examples A on single strap cam travelling wheelhead roll grinder of " 3L CNC ".There is many mat golds hard rock of the convex surface rubber drive wheels of 50 centimetres of diameters, three section headers to support shoe plate on the grinding machine, is positioned at the free pulley of mould circle above and below, also is useful on the shoulder that guides grinding belt.Grinding belt is contained on the machine, and the tension force of grinding belt is 80-100 pound (1417.6N/mm) on the per inch bandwidth, and grinding belt is with the speed running of 7000 surface feet/minute (35 surperficial meter per second).Polished parts are automobile camshafts, and it has Rockwell " C " hardness is the hardened steel cam of 58-60.Axle is with the rotating speed rotation of 20rpm during grinding.Before the grinding, grinding belt has been carried out finishing and finishing, made the workpiece after the grinding can meet the desired precision of producer.During finishing,,, and contact with the surface that drives grinding belt with the rotation of the rotating speed of 5000rpm with the finishing rod of a plating with 4 inches of adamantine diameters (10.2 centimetres).Used cooling agent is the liquid that contains 6% artificial oil (product of Masterchemical Trim, commodity are called VHP E200) in water when finishing and grinding operation.

Obtain qualified surface smoothness and tapering on polished cam, grinding belt need be repaired and finishing with diamond dressing wheel.Through finishing and finishing, just eliminated the grinding cut, make the surface smoothness of workpiece bring up to little cun of 16-30 (0.4-0.8 micron) from 62 little cun (1.6 microns).

Comparative example B

The non junction band that the backing that uses among the comparative example B prepares for the method by announcements in WO 93/12911 such as Benedict.On the very thin non-woven polyester fabric with blade coating on the listed epoxy/polyurethane mixture of table 2.With 30 rhizoids on the per inch (being every centimetre of last 12 rhizoids), with 200 danier glass fibres and polyester capillaries alternately, spiral is involved in this resin.This process is to carry out on the wheel of 132 inches of girths (335.2 centimetres).

The bonding resin of table 2-fiber

Component	Amount
		????UPR	????37.4
????MDA	????4.4
		????PMA	????8.2
????EP1	????16.7
		????EP2	????16.7
????EPH2	????16.7

Initially being sprayed on this backing of the prescription that table 3 is listed in conjunction with coating.Spot printing SAGI (particle mean size is 25 microns) on initially in conjunction with coating, the density of spot printing is 0.057 gram/inch ²If (on the SAGI particle nickel coating being arranged, then is 0.143 gram/inch ²) (0.0088 gram per centimeter ²Or 0.022 gram per centimeter ²).82 ℃ of precuring one hour, the glued coating that table 4 is listed was sprayed on the abrasive particle.Belt solidified 1 hour at 82 ℃, and 103 ℃ solidified 14 hours, solidified 1 hour at 143 ℃ again.It is wide that belt is cut into 7/8 inch (22.2 centimetres).

Table 3-is initially in conjunction with formulation for coating material

Component	Amount
		????DIW	????17.20
????SCA	????0.44
		????CMST	????43.01
????CMSK	????-
		????PR	????38.28
????ASF2	????0.43
		????SWA1	????0.32
????SWA2	????0.32

The glued formulation for coating material of table 4-

Component	Amount
		????DIW	????17.20
????SCA	????0.44
		????CMST	????43.01
????CMSK	????-
		????PR	????38.28
????ASF2	????0.43
		????SWA1	????0.32
????SWA2	????0.32
		????85/15PS100/DIW	????-
????P-320?AO	????-
		????P-400?AO	????-

Grinding condition is identical with Comparative examples A.Grinding belt is repaired and finishing, and its lapped face fineness is brought up to little cun of 16-40 (0.4-1 micron) from 105 little cun (2.6 microns), and has eliminated the grinding cut.After once repairing, before not losing the flatness of wheel, can grind 120 cams on the camshaft, the flatness of cam is substandard just now.Measured the wearing and tearing of grinding belt, calculated G ratio, the volume of the volume that G ratio equals the metal that grinds off from cam grinding belt wearing and tearing when grinding.Be calculated as follows G ratio:

G ratio=(cam girth) (cam is wide) (material that is ground off is thick)/(grinding belt length) (cam width) (thickness that grinding belt reduces)

The G ratio of comparative example B is about 140.Observed maximum tension is 0.6%.

Embodiment 1

Embodiment 1 employed backing is polyester weft sateen fabric (285 gram/rice ²), soak into phenol/latex mixture of 90/10, obtain 360 gram/rice ²Weight.Add an epoxy back sizing menting property, weight is increased to 420 gram/rice ², add pre-sizing menting property, weight is increased to 450 gram/rice ²It is wide that backing is cut into 12 inches (30.5 centimetres).Determine 132.1 inches long, flush at 67 ° of angles, and splice with 3/4 inch (1.9 centimetres) wide splicing thing with a sinusoidal wave die head.Spliced belt is enclosed within on 132 inches of girths (335.3 centimetres), wide 15 inches (38 centimetres) the aluminium matter wheel hub.Scrape the resin of the listed prescription of coating table 5 on backing, coating thickness is about 4-6 Mill (102-152 micron), and weight is 0.036 gram per centimeter ²After the coating, this wheel hub is with 3rpm rotating speed rotation, makes partly solidified 40 seconds of the acrylate of resin with " D " lamp of 600 watts/inch Fusion Systems.

The bonding resin of table 5-fiber

Component	Amount
		????UPR	????48.7
The PMA that contains 35%MDA	????15.2
		????UAO	????18.0
????PEG4D	????17.6
		????PH2	????0.5

Coat the second layer with same resin again, thickness is 16-20 Mill (406-508 micron).With per inch bandwidth 24 rhizoids, 400 daniers (products of the commodity of E.I.DuPont company " Kevlar 49 " by name) and the polyester fiber silk of 440 daniers alternately are rolled onto on the backing.Resin is wipeed off, and solidified 40 seconds with aforesaid Fusion Systems lamp.Belt after the coating shines about 30 minutes (at this moment wheel hub will rotate) again with cured resin under two infrared curing lamps.Behind the cool to room temperature, take off backing from wheel hub, it is wide to be cut into 5 inches (12.7 centimetres).

The preparation of abrasive material agglomerate, be mixed with resin, it be applied in the silicone mold that the perforate at mould top is 0.050 inch (1270 microns) square with the listed prescription of table 6, its bottom is 0.025 inch (635 microns) square, 0.035 inch of hole depth (890 microns).Table 11 has been described the glass powder that is used for embodiment 1-4 slurry that table 8 is listed.Slurry in 90 ℃ of dryings and curing mold 30 minutes.From mould, take out the cube of gained.For preventing that the cube agglomerate bonds together in calcination process, 100 AO and the 10.0 gram DIW that restrain 220 ranks (74 microns of particle mean sizes) are mixed with the cube agglomerate of 200 gram precalcinings.Cover the AO of 220 grades of systems of one deck 75 grams in the bottom of aluminium oxide saggar earlier, put compound again.Saggar is placed in the small-sized stove of a blowing air.In four hours furnace temperature is elevated to 900 ℃ from 25 ℃,, stops heating then and be cooled to ambient temperature overnight afterwards 900 ℃ of insulations 3 hours.Will be through calcining vitrified agglomerate material by 16 purpose sieves, it is separated from each other and removes thin AO.

With the listed prescription of table 9 initially in conjunction with the polyester textile one side of coating blade coating at backing, weight in wet base is 0.22 gram/inch ²(0.034 gram per centimeter ²).With the agglomerate of above-mentioned preparation with 0.34 gram/inch ²(0.053 gram per centimeter ²) the weight point be coated onto on the initial binding resin.Belt is put into 90 ℃ baking oven 90 minutes, make initially in conjunction with coating precuring and agglomerate is bonded on the backing.With the rubber rollers (Xiao Er A hardness=30) of a softness with listed glued resin-coated of table 10 to being with.Glued resin-coated weight is 0.41 gram/inch ²(0.064 gram per centimeter ²).Belt solidified 3 hours at 130 ℃ 90 ℃ of precuring 16 hours.After the curing, with the belt alternating bending for several times, be cut into 1.0 inches (2.54 centimetres) wide tests.

The nonferromagnetic substance of following test grinding belt.Employed grinding machine identical with described in the Comparative examples A.The workpiece that grinds is that rockwell's hardness " C " is 58-64, has the automobile camshaft of 0.453 inch (1.15 centimetres) wide cam that hardens.Before the grinding, under the same conditions grinding belt is repaired and finishing.But the concentration of the oil of cooling agent in water is 5.75%.

The finishing of grinding belt and finishing are to make grinding belt contact with a diamond dressing wheel, make narrow diamond dressing wheel move back and forth on the width on the grinding belt.When grinding belt thickness reaches 0.069 inch (0.176 centimetre), it is fully repaired, to guarantee successfully to grind the cam of camshaft.

Advance mill speed to first protruding abrasive wheel that carries out with 0.001 inch of revolution (25 microns), the flatness that summit on this wheel surface differs to the height overall and the plane of the lowest point is 0.000060 inch (1.5 microns), and average surface profile is 20 little cun (0.5 microns).After having ground 48 cams, surface smoothness drops to 28 little cun (0.7 micron), and flatness is reduced to 0.000130 inch (3.3 microns).Record the wearing and tearing of grinding belt, cam of every grinding is 0.0000045 inch (0.114 micron).Calculating G ratio is 96.

Once more grinding belt is repaired and finishing.Thickness to band is reduced to 0.067 inch (0.172 centimetre).The mill speed of advancing with 0.001 inch of camshaft revolution (25.4 microns) is ground first cam.Drawing its surface smoothness is 21 little cun (0.55 micron), the flatness that summit on this wheel surface differs to height overall and its plane of the lowest point is 0.000080 inch (2.03 microns), after grinding 48 cams, surface smoothness drops to 28 little cun (0.7 micron), and flatness is reduced to 0.000100 inch (2.54 microns).Record the wearing and tearing of grinding belt, cam of every grinding is 0.0000031 inch (0.078 micron).Calculating G ratio is 139.

Again grinding belt is repaired and finishing, made its thickness reduce to 0.0669 inch.Advance mill speed and be increased to 0.0015 inch of revolution.Ground first cam, surface smoothness is 24 little cun, and flatness is 0.00010 inch (2.03 microns).After grinding 48 cams, surface smoothness drops to 35 little cun, and flatness is reduced to 0.000210 inch.Record the wearing and tearing of band, cam of every grinding is 0.0000075 inch (0.078 micron).Calculating G ratio is 58.

Again grinding belt is repaired and finishing, made its thickness reduce to 0.0659 inch.Advance mill speed and be reduced to 0.00067 inch of revolution.Ground first cam, surface smoothness is 21 little cun, and flatness is reduced to 0.000085 inch.After grinding 118 cams, surface smoothness drops to 24 little cun, and flatness is reduced to 0.000170 inch.Record the wearing and tearing of grinding belt, cam of every grinding is 0.0000021 inch.Calculating G ratio is 206.

In comparative example,, under similarity condition, fail to reach the above-mentioned flatness of cam with same equipment with the grinding belt that disperses abrasive particle (not being its agglomerate) preparation.

To above-mentioned grinding belt, repair one by one with finishing to meet the requirements of flatness.Want success and use grinding belt to carry out the grinding of camshaft effectively, importantly should can obtain the flatness that cam grinds always.

Embodiment 2

Prepare embodiment 2 employed backings by the mode similar to embodiment 1, difference is that the resin formula that viscose fibre is used is that table 6 is listed, has also described other below and has been different from embodiment 1 part.

The resin of table 6-fiber bonding

Component	Amount
		????UPR	????66.5
????AC	????7.8
		????MAA	????0.1
????PEG4D	????25.0
		????PH2	????0.6

Behind coating resin on the backing, with the 3rpm swing roller, and with 400 watts/inch Fusion Systems " V " lamp cured resin 60 seconds.

Coat the same resin of the second layer, thickness is 16-20 Mill (406-105 micron).800 denier fibers of the commodity of E.I.DuPont company " Kevlar " by name are wound on the backing with 42 of per inch bandwidth.Resin is wipeed off, made resin solidification 60 seconds with same Fusion Systems lamp again.To be subjected to two infrared curing light irradiations about 120 minutes through the belt of coating (this simultaneously cylinder rotation) with cured resin.Behind the cool to room temperature, take off backing from cylinder, it is wide to be cut into 5 inches (12.7 centimetres), is used for coating.

Press embodiment 1 mode mixture table 8 listed slurry with preparation vitrifying agglomerate.Slurry in 90 ℃ of dryings and curing mold 30 minutes.From mould, take out the cube agglomerate with helping of ultrasonic feeler.For preventing that agglomerate bonds together in calcination process, the AO of 100 gram 150 ranks (105 microns of particle mean sizes) and the agglomerate material of precalcining are mixed.Bottom at the aluminium oxide saggar covers 150 grades of other AO of one deck earlier, puts compound again.Saggar is placed in the small-sized stove of a blowing air.900 ℃ of calcining agglomerate.Will be through calcining vitrified agglomerate material by 16 purpose sieves, it is separated from each other and removes thin AO.

With the listed prescription of table 9 initially in conjunction with the coating blade coating on backing, it is heavy to be 0.21 gram/inch ²(0.033 gram per centimeter ²).With the agglomerate of above-mentioned preparation with 0.57 gram/inch ²(0.088 gram per centimeter ²) the weight point be coated onto on the initial binding resin.Belt is put into 90 ℃ baking oven 90 minutes, make initially to be bonded on the backing in conjunction with coating precuring and with agglomerate.

With a soft rubber roller (Xiao Er A hardness=30) with listed glued resin-coated of table 10 to being with.Glued resin-coated weight is 0.50 gram/inch ²(0.0775 gram per centimeter ²).Belt precuring 90 minutes in 90 ℃ of baking ovens was solidified 10 hours at 105 ℃, solidified 3 hours at 130 ℃.After the curing, with the belt alternating bending for several times, it is wide to be cut into 0.75-1.0 inch (1.9-2.5 centimetre), tests.

Nonferromagnetic substance to hardened steel cam test grinding belt.Employed grinding machine is the prototype belt grinding machine to the similar basically J.D.Phillips company of Litton Landis grinding machine.Supporting shoe plate is a polymorphic diamond shoe plate, has placed free pulley in the above and below of shoe plate, and all there is the flange of guiding grinding belt on each limit of shoe plate.With the convex surface rubber drive wheels of 12 inches of diameters (30.5 centimetres), with the tension force of 50-73 pound/inch (8.8-12.8N/mm) and the speed drive belt of 7740 surface feet/minute (39.3 meter per second).With 3 inches of diameters (7.6 centimetres) rotating speed is that the 10rpm diamond wheel is repaired and finishing grinding belt.About 1/2 inch of the contact width of diamond wheel and band (1.27 centimetres).The diamond of rotation is in from left to right laterally operation on belt of the left side of band conversion.The workpiece that grinds is the automobile camshaft that is used for bent-eight, the rockwell's hardness of its cam " C " is 60-62, size is about 0.45 inch (1.14 centimetres), and used cooling agent is the mixed liquor of a kind of artificial oil (Cimperial 1010) and water, and the concentration of oil in water is 5%.

Before finishing, finishing and grinding, grinding belt thickness is about 0.100 inch (0.25 centimetre).It is that grinding belt is contacted with diamond dressing wheel that grinding belt is repaired with finishing, makes diamond wheel slowly cross the width of grinding belt, when belt thickness reaches 0.085 inch, it is fully repaired, to guarantee successfully to grind the cam of camshaft.

Eight statures on the test grinding machine, each can grind two cams on the camshaft.Grind two cams in front earlier, then grinding belt is moved to second stature and grind third and fourth cam.The maximum cam number that not mobile grinding belt can grind is 94.

428 cams have been ground with grinding belt.This moment, the wearing and tearing of grinding belt were still slight, so can not accurately measure its wearing and tearing and calculate G ratio.

The surface smoothness of the cam basal plane that begins to grind after the grinding belt finishing is about 13 little cun (0.325 micron) at first.After grinding 180 cams, the surface smoothness of basal plane still is 20 little cun (0.5 micron).The final stretching of band is approximately less than 1.8%.

Embodiment 3

Mode by embodiment 2 prepares embodiment 3 employed backings, and difference is for using the listed bonding resin of fiber of table 7.

The bonding resin of table 7-fiber

Component	Amount
		????UPR	????67.2
????AC	????7.8
		????MAA	????0.1
????PEG4D	????24.4
		????PH2	????0.5

With the slurry of the listed prescription of table 8, prepare the abrasive material agglomerate by the method for embodiment 2.For preventing that the precalcining agglomerate bonds together in calcination process, the SAG2 of 200/230 rank (74 microns of particle mean sizes) is mixed with the agglomerate material.Aluminium oxide saggar bottom covers with 200/230 grade of other SAG2, puts compound again.Saggar is placed in the small-sized stove of a blowing air.900 ℃ of calcinings.Will be through calcining vitrified agglomerate material by ANSI 16 purpose sieves, it is separated from each other and removes thin SAG2.

With the listed prescription of table 9 initially in conjunction with the polyester textile one side of coating blade coating at backing, its weight is 0.25 gram/inch ²With the agglomerate of above-mentioned preparation with 0.73 gram/inch ²The weight point be coated onto on the initial binding resin.Belt is put into 90 ℃ baking oven 90 minutes, make initially in conjunction with coating precuring and agglomerate is bonded on the backing.With a soft rubber roller (Xiao Er A hardness=30) with listed glued resin-coated of table 10 to being with.Glued resin-coated weight is 0.43 gram/inch ²Belt solidified 10 hours at 105 ℃ 90 ℃ of precuring 90 minutes, solidified 3 hours at 130 ℃.After the curing, with the belt alternating bending for several times, be cut into wide test of 0.75-1.0 inch (1.9-2.5 centimetre).

The nonferromagnetic substance of test grinding belt on the hardened steel cam and the cast iron that hardens.Grinding condition is as follows.Employed grinding machine is the Litton Landis grinding machine among the top embodiment.Convex surface rubber wheel with 20 inches of diameters (50.8 centimetres), with the tension force of 80-100 pound/inch (14-17.6N/mm) and surperficial 6000-11000 surface feet/minute the speed drive belt, this rubber wheel was beaten with thick abrasive material and was made its rough surface, reduced the slip of grinding belt on driving wheel.Mode by the front is repaired and finishing grinding belt.About 1/8 inch of the contact width on diamond dressing wheel and grinding belt surface (0.32 centimetre), this takes turns when changeing the from left to right transverse movement of the left side by grinding belt, commutation more afterwards, transverse movement from right to left.To be rockwell's hardnesses " C " be the cast iron cam shaft of 48-50 for the automobile camshaft and the rockwell's hardness " C " of the hardened steel of 58-64 to the parts that grind.During grinding, cam rotates with 20rpm, and does oscillating movement with 1.4Hz and amplitude 0.120 inch (0.3 centimetre).Cooling agent is Masterchemical Trip VHP E200, and its concentration is 3-6%.

Before finishing, finishing and grinding, grinding belt thickness is about 0.130 inch (0.33 centimetre).Backing thickness is 0.050 inch (0.127 centimetre).What apply on grinding belt is that one deck diameter is about the agglomerate of 0.040 inch (0.102 centimetre).Some agglomerate have also by mistake been coated as the second layer.But these extra agglomerate have come off time during initial finishing/finishing.

It is will grinding belt be contacted with a diamond dressing wheel that grinding belt is repaired with finishing, and the narrower diamond wheel of order moves around on bandwidth.When belt thickness reaches 0.089 inch (0.226 centimetre), grinding belt fully repaired with finishing guarantee successfully to grind the cam of camshaft.

To the cam of hardened steel camshaft, the G ratio range under various grinding conditions is 60-110.To the cast iron cam that hardens, the G ratio range is 98-427.

During test, the stretching of band is less than 1.0%.When the tension force that applies remove overnight after, grinding belt be returned to its former length 0.5% in.

Embodiment 4

The method of embodiment 3 prepares the grinding belt of present embodiment.Backing preparation method by embodiment 3 prepares backing and abrasive material agglomerate, and difference is long 158 inches (400 centimetres) of the grinding belt that obtains, wide 1.0 inches (2.54 centimetres).

The initial binding resin blade coating that table 9 is listed is to the polyester textile one side of backing, and coating weight is 0.21 gram/inch ²(0.105 gram per centimeter ²).With 0.68 gram/inch ²(0.105 gram per centimeter ²) above-mentioned agglomerate point is coated onto on the initial binding resin.Belt is put into 90 ℃ baking oven 90 minutes, makes initial resin precuring, and agglomerate is bonded on the backing.

With a soft rubber roller (Xiao Er A hardness=30) with listed glued resin-coated to belt of table 10.Glued weight resin is 0.27 gram/inch ²(0.042 gram per centimeter ²).Belt precuring 90 minutes in 90 ℃ baking oven was solidified 10 hours at 105 ℃, solidified 3 hours at 130 ℃.After finishing curing, with the belt alternating bending for several times, be cut into 1.0 inches (2.54 centimetres) wide tests.

By following test grinding belt.The grinding machine of test usefulness is single belt camshaft grinding machine machine of the model C BS1 of German Schaudt.Support shoe plate wide 1.07 inches (2.73 centimetres), placed the free pulley of convex surface in the above and below of shoe plate, the tension force on the grinding belt is 50 pounds/inch ²(8.8N/mm), by 15 inches of diameters (38 centimetres), the rubber wheel of wide 3 inches (7.5 centimetres) is with 9000 surface feet/minute (45 surperficial meter per second) speed drive, and this rubber wheel is beaten slightly to cross with coarse grained abrasive and made the surface smart rough, to reduce the slip of grinding belt on driving wheel to greatest extent.The parts that grind are the cast iron automobile camshafts (rockwell's hardness " C " is 54 in the hypotenuse and the end of cam, is 42 on basal plane) that harden, and widely are about 0.5 inch (13 millimeters).The cooling agent that uses during grinding is OemetaFrigimet MA 174-N, and concentration is 2.5% in the water.

With 5.9 inches of diameters (15 centimetres), the diamond wheel of wide 0.012 inch (0.3 millimeter) is repaired and finishing grinding belt with 3000 feet per minute clocks (15 meter per second) rotation.The diamond wheel of rotation on the right side of band, laterally passes through earlier from right to left, and transposition is horizontal from right to left again.

I.e. 1520 cams of 190 camshafts have been ground with each milling cycle of taking turns 34 seconds.At the test initial stage, repair and finishing grinding belt per five camshafts (40 take turns) back.The camshaft radical that grinds between adjacent finishing and finishing is increased to 36 (288 cams) gradually, still is in the specification requirement scope because confirmed workpiece.Calculating the total G ratio that grinds 1520 cams is 300, and this value is lower, and this is because grinding belt is too much in finishing of test initial stage and finishing number of times.To back 560 cams that grind, G ratio is 1000.In the test with stretching less than 0.7%.

Table 8 is listed the abrasive material agglomerate slurry prescription of the abrasive material agglomerate that is used to prepare embodiment 1-4.

Table 8-vitrifying agglomerate slurry

Component	Embodiment 1	Embodiment 2	Embodiment 3	Embodiment 4
					????SAG2	????47.2	????56.8	????47.2	????47.2
Level	????200/230	????120/140	????140/170	????140/170
					Glass powder	????17.7	????21.2	????17.7	????17.7
????EP1	????6.8	????2.7	????6.8	????6.8
					????EPH1	????3.0	????1.2	????3.0	????3.0
????PS100	????3.0	????3.9	????3.0	????3.0
					????85/15?PS100/DIW	????22.3	????14.2	????22.3	????22.3

Table 9 and 10 described respectively embodiment 1-4 initially in conjunction with coating and glued coating.

Table 9-is initially in conjunction with formulation for coating material

Component	Embodiment 1	Embodiment 2	Embodiment 3	Embodiment 4
					????DIW	????17.6	????10.83	????10.83	????10.83
????SCA	????0.5	????0.20	????0.20	????0.20
					????CMST	????43.4	????-	????-	????-
????CMSK	????-	????51.10	????51.10	????51.10
					????PR	????37.7	????36.57	????36.57	????36.57
????ASF2	????0.4	????0.80	????0.80	????0.80
					????SWA1	????0.2	????0.25	????0.25	????0.25
????SWA2	????0.2	????0.25	????0.25	????0.25
					Knoop hardness	????88-89	????90-100	????90-100	????90-100

The glued formulation for coating material of table 10-

Component	Embodiment 1	Embodiment 2	Embodiment 3	Embodiment 4
					????DIW	????12.3	????17.70	????17.70	????17.70
????SCA	????2.0	????0.30	????0.30	????0.30
					????CMST	????32.9	????-	????-	????-
????CMSK	????-	????52.00	????52.00	????52.00
					????PR	????30.0	????29.0	????29.0	????29.0
????ASF2	????0.4	????0.50	????0.50	????0.50
					????SWA1	????0.2	????0.25	????0.25	????0.25
????SWA2	????0.2	????0.25	????0.25	????0.25
					????85/15?PS100/DIW	????4.2	????-	????-	????-
????P-320?AO	????8.9	????-	????-	????-
					????P-400?AO	????8.9	????-	????-	????-
Knoop hardness	????100-105	????100-105	????100-105	????100-105

In slurry, use the listed glass powder of table 11 according to table 8.Glass powder is ground to its granularity less than 325 orders.The thermal coefficient of expansion substantially the same (3.5 * 10 of the super abrasive grain that uses among the thermal coefficient of expansion of the glass powder that forms and the embodiment ^-6/ ℃).Epoxy resin is as the temporary bonding agent of agglomerate.In prescription, add boron oxide, in order that the bonding between reinforcing glass and abrasive particle.

The prescription of table 11-glass powder

Component	Amount
		Silica	????51.5％
Boron oxide	????27.0％
		Alundum (Al	????8.7％
Magnesia	????7.5％
		Zinc oxide	????2.0％
Calcium oxide	????1.1％
		Sodium oxide molybdena	????1.0％
Potassium oxide	????1.0％
		Lithia	????0.5％
Total amount	????100.0％

Claims (10)

1. coated abrasive article, it comprises:

(a) backing of first first type surface is arranged;

(b) be coated in abrasive material on first first type surface, abrasive material has a contact-making surface and a reverse side, and contact-making surface adheres on first first type surface, is abrasive material thickness from the contact-making surface to the reverse side, contains in the abrasive material

(i) the bonding system of organic group,

(ii) be bonded in the many abrasive material agglomerate in the bonding system, each agglomerate

(1) contain an inorganic bond and many abrasive particles,

(2) its size and shape are even basically,

It is characterized in that perpendicular on thickness and the abrasive material cross section by mid-depth point, total cross-sectional area of its abrasive material agglomerate with by substantially the same to 75% the some cross section of contact-making surface distance from central point along thickness.

2. coated abrasive article as claimed in claim 1, its feature are that also backing is that stretch percentages is approximately less than 2% low stretching backing.

3. coated abrasive article as claimed in claim 1, its feature are that also the bonding system of organic group comprises one initially in conjunction with a coating and a sizing menting property, initially is at least 70KHN in conjunction with the average Knoop hardness that has one deck in coating and the sizing menting property at least.

4. coated abrasive article as claimed in claim 1, its feature are that also these many abrasive particles are the abrasive particles that are selected from the superabrasive of diamond, cubic boron nitride and combination thereof.

5. coated abrasive article as claimed in claim 1, its feature also are section four sides pyramid that is shaped as of each agglomerate.

6. coated abrasive article as claimed in claim 1, its feature are that also each agglomerate is a cube.

7. coated abrasive article, it comprises:

(1) backing of first first type surface is arranged;

(2) be coated in abrasive material on first first type surface, contain in the abrasive material:

(a) the bonding system of organic group,

(b) be distributed in many abrasive material agglomerate in the bonding system, each agglomerate contains an inorganic bond and is shaped as the many abrasive particles that cut the four sides pyramid.

8. method of making coated abrasive article is characterized in that it comprises:

(a) provide a backing that first first type surface is arranged;

(b) form abrasive material, abrasive material has a contact-making surface and a reverse side, contact-making surface adheres to first first type surface of backing, from the contact-making surface to the reverse side abrasive material thickness, wherein perpendicular on thickness and the abrasive material cross section by mid-depth point, total cross-sectional area of its abrasive material agglomerate with by from central point along thickness to 75% some cross section of contact-making surface distance, substantially the same, it comprises

(1) first first type surface at backing is coated with initially in conjunction with coating, and this coating contains a kind of first organic group binder precursor;

(2) provide many abrasive material agglomerate, these abrasive particle condensates

(i) contain a kind of inorganic bond and many abrasive particles,

(ii) its size and shape are even basically;

(3) agglomerate is dispersed in initially in conjunction with in the coating;

(4) a kind of effect of the energy is initially accepted in order in conjunction with coating, makes first binder precursor partly solidified at least;

(5) the glued coating of coating on the abrasive material agglomerate, this gluing coating contains the second organic group binder precursor;

(6) sizing menting property is accepted the effect of the another kind of energy, second binder precursor is solidified, and first binder precursor is solidified fully.

9. one kind is ground the method that rockwell's hardness is at least 25 hard workpiece, it is characterized in that it comprises

(1) provide one to comprise a kind of coated abrasive article that contains backing and abrasive material, a bonding system and abrasive material agglomerate are arranged in the abrasive material, agglomerate contains:

(a) there is not the inorganic, metal oxide of free metal basically

(b) be essentially the abrasive particle of superabrasive abrasive particle;

(2) coated abrasive article is contacted with workpiece;

(3) make coated abrasive article and workpiece do relative motion.

10. before method as claimed in claim 9, its feature also are grinding tool and workpiece contacts,, reach precise finiss to hard workpiece by coated abrasive article is carried out finishing.

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