DE1916110A1 - Press powder mass - Google Patents

Description

Dipl. Ing.F.Weickmann, Dipl.lng. H.Weickmann, Dipl.Phys.Dr.K.Flnckl Dipl. Ing. F. A. Weickmann, Dipl. Chem. B. Huber

8München27, Höhlitr. 22

Sch / Gl

NORXON ABRASIVES LIMITED, Welwyn Garden City, Hertfordshire, England

Press powder mass

The invention relates to food powder, which in particular for the production of a matrix for a grinding element or have a core used for a grinding wheel.

Molding powder compounds often contain a resin with a filler, v / which is intended to impart the desired properties to the molded article. For example, glass fibers can be used as a filler can be used to give strength to the molded article. Furthermore, a metal powder can be used to

90984 1/1557

BATH ORIGINAL,

a molded article having a high thermal conductivity equip.

It has now been found that the use of a non-metallic filler in a resin in combination with a metal powder has a greater strength and thermal conductivity than This is the result of a combination of the leagues of either the non-metallic filler or metal powder, respectively fllr »ion alone rented with dta Hare, was to be expected were, but follow · has.

Then the cargo is a Prtespulvtraasee we available placed, dl · «in hair» «in a non-metallic filler and contains a metal powder. Babel aaohtn der nieht-metalli «= · see filler 8 - 46 Voluaen-jt of the total mass and the metal powder 8-20 toluene- ^ dtr of total mass.

A combination of strength and thermal conductivity required of cores for sole wheels. Duroh the invention will now a core for a grinding wheel is provided, which has been produced from the press powder composition according to the invention. The powder mass was also used as a matrix for a Abrasive element are used, wherein an abrasive powder of the matrix is exposed to form a grinding element.

For grinding cemented tungsten carbide or other hard ones Materials are usually abrasive = interspersed with elements washers used. Ser-like disks "consist of a diamond-bearing surface that is attached to a base that does not contain diamond. This base is called a called preformed core or carrier.

90984171557

BATH ORIGINAL

The core materials used up to now usually consist of a hit-hardening molding material that contains either mineral fillers, such as asbestos fibers, or metallic fillers, such as aluminum powder. Solid metals such as aluminum or its alloys can also be used as cores. However, all these materials have disadvantages . The technically produced materials filled with mineral fillers have, despite their good strength properties, a very poor thermal conductivity, so that their use is limited to such grinding operations, coolants can be added when they are carried out. If heat is to be dissipated from the contact surface via the disc body, as is the case when grinding "hard metal" without the use of a coolant, use a metal body or press powder filled with a metal powder, such as aluminum.

Solid metal cores are limited to simple shapes. In addition, these cores come into question »if the core does not have to be removed after the diamond-containing © grinding edge has worn out. With metal powders filled © Press powders are i despite their good Verarbeitungseigensehaften and thermal conductivity relatively soft and weak. With the development of diamonds and binding materials of old improved quality, higher grinding pressures are adhered to, and your energy consumption also increases. This has the consequence that the binding material fails during the normal service life of the grinding wheel, which -, * has the consequence that the diamond edges separate from the core

It has now been found that diamond grinding wheels with cores which wor produced from the press powder mass according to the invention

90 98 4 1/1 55 7

BAO ORIGINAL

• J £ &; S: Sft: BÖ- otÄigÄnÄÄr; llfetalX- '; pulver mix, and awar Me z} i'ws ^^^ i2QL, Y &] Lvm ^^^ / '^ ® ^' ^ '^^^ ^{:! ss} powder, rises. It has also been found that metal powders give better results than metal powders in the form of lpag @ l-shaped powders. = are conductive and can also be deformed in the usual way.

• The following examples © explain the invention.

example 1

An upright grinding wheel with a diameter !? of 254 ram (10 inches) and a width of 19 _p ö nra (3/4 inch) with a 76 iEra => hole contains a © Diamant-Se & Leifschicht (from 9.8 Voluzaazi «? £ diamond and 90» 2 $ one Phenolenaaldshya resin (manufactured by Bakelite Limited) in a depth of 1.6 Esm (1/16 inch) around its circumference * The core material consists of an asbestos-filled phenolic press powder (marketed by Birkbv ^ s Ltd. under the name So 808/1 with a content of .40 volume ^ asbestos filler) s deai 50 weight ^ (15.7 volume * * ^) of an electrically conductive copper powder (rope, which through #rf sieve with a A clear width of 0.05 mm (-500 inches to pass through) have been mixed in. The core is manufactured in the usual way, namely by introducing the compound into a suitable form and by hardening it

BATH ORIGINAL

and pressure. The core is then. on its circumference saves and put back into shape. Dana gets the mix from diamond and resin poured into the cavity, followed by heating under pressure. In this way the diamond grinding = edge connected to the core. The disc is then used to set the exact shape before finishing and Grösee hardened in an oven. At a constant Grinding speed is the life of the disc around 40. larger than the one that has been known to be satisfactory so far th products that have the same mixture of resin and diamond, but with a different core.

A beveled dome wheel with a diameter of 5 / 3.11 / 16 inches and a depth of 44 am (1 3/4 inches) with a 31.7 bm (1 1/4 inches) hole has a dia manten grinding part (with a composition similar to the abrasive layer according to Example 1, but this layer contains 8.6 volumes «· ^). This rope is in a Depths of 1.6 mm (1/16 inch) and a length of 11.1 mm (7/16 inch) on the tape of the 5 inch diameter knife. The disk v / e is a core on j which has been produced using a copper-containing powdered powder, the composition of this press powder being that in example 1 is similar to the composition described. However contains the pressed powder 8.6 volumes »^ silicon carbide instead of asbestos and 58.6 volumes - = ^ of the resin. This disc can be in a satisfactory manner for sanding cemented Use tungsten carbide. The previously known discs ,, the are identical to the disks according to the invention in every respect, with the exception that they have different core materials contain, fail either as a result of a failure to

9 0 9 8 4 "f y 15 5 7

BATH ORIGINAL

■ ■ - 6 -. ■ '; ■ - ■ "■';

lust or as a result of overheating.

It has been found that, if the mass is used as a core for a grinding wheel, the rope size of the metal powder should preferably be such that the 3 pieces pass through a sieve with a mesh size of 0.05 in (300 mesh ) go through "In addition, the best combination of! strength and thermal conductivity is then achieved _p when 16 vol mechanical strength. If electrical conductivity is required, then the proportion of metal powder should be sufficient to produce the required electrical conductivity. Other metal powders can be used, for example powders made of aluminum, silver, metal alloys or coated metals, eg iron or copper, which is coated with silver.

The non-metallic filler can be made of any suitable material. Preferably an inorganic fibrous material is used, Bsispielsiireise konratn glass fibers, carbon stoffasem W, silicon carbide or AluminiuMoxjdfasern into consideration.

90 98 41/1557

BATH

Claims (14)

wmmmm rtiche; 1 _# - powder compound, geke nnBeichne t by an ear ζ, a and a Met ^ lpjtailyer j being the Ö ~ 4 £ V ^ volumen ^ dfepf Sesaatmass and the metal powder S - 2) 0; Volume ^ of ee # amii: raaaae make up. 2. Composition according to claim T, characterized in that the ™ Hara made from a phenol aldehyde resin. 3. Composition according to claim 1 or 2, characterized in that the non-metallic filler is a mineral filler is. 4. Hasse according to claim 3, characterized in that the non-metallic filler an inorganic fibrous Material is. 5. Composition according to claim 4, characterized in that the Non-metallic filler is made up of asbestos. G 6. mass according to one of claims 1-5 »marked thereby-» net that the metal powder is made of copper. 7. Composition according to one of claims 1 - *>, characterized in that the metal powder consists of aluminum or silver. 8. mass according to one of claims 1 ~ 5i, characterized in that that the metal powder consists of an alloy. 9. Composition according to one of claims 1 -5, characterized in that BADORiGlNAL - ^ net that the metal powder from a soaked with metal Consists of metal powder. BATH ORIGINAL Claims 10. Use of the molding powder composition according to one of claims 1 to 9 for the production of a grinding element which Contains abrasive particles in a matrix which has been made from the molding powder mass. 11. Use of the pressed powder composition according to one of the claims 1 to 8 for the production of a grinding wheel in which a grinding wheel is attached to a core and the core is made of " the powder molding compound has been produced. 12. Use according to claim 11, wherein the abrasive article . the grinding wheel contains diamonds. 13. Use of a molding powder composition according to claim 1 to 9 containing a dendritic metal powder for the purpose of claim 10 or 11. 14. Use of a Preßpulvermasse according to any one of claims 1 to 9, wherein the metal powder particles pass through a sieve having a mesh width of 0.05 mm hindurch- i for the purpose of claim 1 to O. 13 909841 / t55 7 BATH ORIGINAL