EP0004449A2 - Procédé de fixation pour outils abrasifs - Google Patents

Procédé de fixation pour outils abrasifs Download PDF

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Publication number
EP0004449A2
EP0004449A2 EP79300429A EP79300429A EP0004449A2 EP 0004449 A2 EP0004449 A2 EP 0004449A2 EP 79300429 A EP79300429 A EP 79300429A EP 79300429 A EP79300429 A EP 79300429A EP 0004449 A2 EP0004449 A2 EP 0004449A2
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EP
European Patent Office
Prior art keywords
workpiece
plating bath
metal
abrasive particles
process according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP79300429A
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German (de)
English (en)
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EP0004449A3 (en
EP0004449B1 (fr
Inventor
J. Lawrence Fletcher
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Individual
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Individual
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Filing date
Publication date
Priority claimed from US05/888,081 external-priority patent/US4155721A/en
Application filed by Individual filed Critical Individual
Publication of EP0004449A2 publication Critical patent/EP0004449A2/fr
Publication of EP0004449A3 publication Critical patent/EP0004449A3/en
Application granted granted Critical
Publication of EP0004449B1 publication Critical patent/EP0004449B1/fr
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • B24D18/0018—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for by electrolytic deposition
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D15/00—Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires

Definitions

  • This invention relates to a process for bonding abrasive particles to the surface of a metal workpiece.
  • the hardness and abrasive qualities of diamonds are well known, particularly those of synthetically produced virgin polycrystalline diamond particles.
  • Virgin polycrystalline diamond particles are of particular interest because of their greatly increased number of sharp points or cutting edges and lack of fracture planes.
  • Tools such as for sharpening and grinding have been prepared from natural and synthetic diamond particles by bonding these particles together in the form of a sharpening stone using a ceramic or polymeric matrix to bond the diamonds into a unitary structure.
  • this process consumes an excessive amount of diamond particles, and the ceramic structure is also easily susceptible to fracture.
  • such tools have increasingly been prepared by bonding diamond particles to the surface of a metal workpiece, while immersed in an electrolytic plating bath, by electrodeposition of a metallic bonding matrix on to the workpiece and around the diamond particles.
  • tools produced according to this latter process have generally been more durable and less expensive to make than the ceramically bonded tools, they have nevertheless evidenced an inherent weakness in that the diamond particles tend to be pulled from the metal workpiece by abrasive action during use of the tool. It has been found that pulling out of the diamond particles can be minimised by controlling the hardness of the metallic bonding matrix or by increasing the thickness and controlling the hardness of the metallic bonding matrix.
  • the hardness of a metallic bonding matrix can be changed by changing the type of metal used and/or by heat treatment, for various kinds of metals.
  • glazing is caused by one of two conditions. If a given material is cut or ground, minute particles (called “swarf”) tend to fill in the crevices between the diamond particles. Thus, one reason the cutting edge may become glazed is because the swarf is not abrasive enough to erode away the bonding matrix at the same rate as the diamond particles are being worn down. The other reason the cutting edge may become glazed is because the metal bonding matrix is not slick enough, and thus swarf will adhere to the bonding matrix and will fill in the crevices as described above.
  • swarf minute particles
  • the present invention provides a process for bonding abrasive particles to the surface of a metal workpiece by immersing the workpiece and the abrasive particles in an electrolytic plating bath comprising an aqueous solution of metal ions and electrodepositing a metallic bonding matrix on to the workpiece surface and around the abrasive particles adjacent the surface, the process being characterised in that prior to such electrodeposition the surface of the workpiece is etched to form cavities therein of dimensions such that each cavity is capable of receiving a portion of one abrasive particle and, subsequently to said etching step, the workpiece is at least partially embedded in a layer of the abrasive particles in the plating bath and an electromotive force is imposed across a metal anode in the plating bath and the workpiece whereby the abrasive particles become individually partially embedded in the cavities of the etched workpiece surface as the metal is plated on to the workpiece and around the embedded particles, and in that subsequent to said electrodeposition step the workpiece is at least partially immersed
  • Etching is believed to create small cavities in the workpiece surface, each cavity being adapted to individually receive a portion of an abrasive particle, thereby providing for a stronger mechanical bond between the particle/metal plated surface of the workpiece by recessing at least a part of the abrasive particle below the shear plane.
  • the swarf will not significantly adhere to the matrix and the swarf will evenly wear down the second coat of metal veneer, thus maintaining a cutting edge so as to prevent glazing.
  • the choice of type and thickness of the second metal coating will therefore depend on the ultimate use of the tool. Heat treatment after the second plating step can serve to control stresses in the plated surfaces and thereby provide a stronger bonded surface on the workpiece to prevent pulling out of the abrasive particles.
  • Partial or complete embedding of the etched workpiece in the layer of abrasive particles ensures the even distribution of the particles during plating in the first-mentioned plating bath. Such even distribution may also be enhanced by gentle rotation of the workpiece, care being taken not to dislodge particles already bonded to the workpiece.
  • a workpiece that is plated with diamond particles in accordance with the present invention advantageously incorporates the durability of diamond with the versatility of a metal substrate. While natural diamond or static synthesis diamond grit can be used, synthetically produced virgin polycrystalline diamond grit or particles are particularly useful due to their increased surface irregularities as compared to natural or static synthesis diamond particles.
  • Plating these diamond particles on to the surface of a metal workpiece provides a tool with an abrasive surface useful for many grinding and lapping applications, for example, those found in grinding wheels, lapping wheels, hones, tool sharpeners, etc..
  • a layer of diamond particles is bonded to the surface of a metal workpiece through electrodeposition of nickel or other suitable metal to the workpiece.
  • Diamond particles do not, in themselves, electroplate on the metal workpiece but are entrapped by the metal as it is electroplated thereon.
  • Uniform dispersion of diamond particles is assured by partially or totally embedding the workpiece in a layer of the diamond particles in an electroplating bath while an electromotive force imposed upon the bath assists in attracting the diamond particles to the workpiece, thereby enhancing the predetermined population and uniform packing of diamond particles on the workpiece surface.
  • the workpiece is surrounded by diamond particles which may be uniformly plated on to the workpiece in a substantially quiescent bath.
  • the workpiece After a predetermined layer of diamond particles has been bonded to the surface of the workpiece by the plating action of the metal, the workpiece is immersed in a second plating bath. There, a second coat of only metal is deposited over the diamond/metal surface.
  • this second coating of metal has the surprising advantage of wearing down evenly as the abrasive particles wear. This helps to prevent glazing of the cutting edge due to filling of the crevices between abrasive particles.
  • this second coat of metal wears, the abrasive particles will not loosen and pull out since they will remain firmly bonded to the cavities of the workpiece surface by the remainder of the second coat and by the first coat of metal.
  • the second plating step is then followed by heat treatment of the workpiece so as to harden and toughen the metal and relax any stresses that may have developed during any of the previous processing steps.
  • the temperature during heat treatment is held below the decomposition temperature of the diamond particles to preclude thermal decomposition.
  • a workpiece 10 is shown in an etching bath 14 comprising a solution 15 of aqueous sulphuric acid.
  • aqueous sulphuric acid has a 60% sulphuric acid concentration.
  • an electromotive force indicated at 12 is imposed between workpiece 10 and a cathode 16 or even a metal vessel 13 containing the acid solution 15.
  • a reverse DC current of about four amps at five to six volts for six or seven minutes has been found adequate.
  • workpiece 10 may be rotated either continuously or intermittently in the bath with a rotatable shaft 18.
  • Rotation of shaft 18 and workpiece 10 also agitates the solution and minimises undesirable concentration of electrolytic action of any one portion of the surface of the workpiece thereby assuring more uniform etching. After etching, any remaining sulphuric acid is removed by rinsing workpiece 10 with water.
  • an oxide coating may readily form on the surface of the workpiece after it is removed from the vessel 13 and rinsed.
  • Plating bath 20 may contain any suitable metal plating solution.
  • plating bath 20 contains a nickel plating solution 22 which may be a standard aqueous solution of nickel sulphate and nickel chloride heated to about 50° C .
  • This plating solution is well known in the art and is commonly referred to as a standard Watts bath.
  • the plating solution includes about 110 to 380 g/l nickel sulphate and about 60 to 302 g/l nickel chloride in a boric acid buffer.
  • Diamond particles 25 are provided as a layer 46 in the aqueous solution 22 at the bottom of the bath 20 so as to facilitate uniform distribution of diamond particles 25 about the workpiece 10 which is embedded in the layer 46.
  • Diamond particles 25 may be of any suitable size although the very fine particles (24 to 41 microns) are preferred for sharpening tools and the like. Grinding wheels and related tools may require particle sizes upwards of 24 mesh.
  • Workpiece 10 is mounted upon a shaft 32, which may be rotatable, and suspended in plating bath 20.
  • the workpiece may, if necessary, be rotated during plating to ensure an even dispersion of the particles on the workpiece surface, but care should be taken not to dislodge particles already bonded to the surface.
  • a nickel anode 34 is also suspended in plating bath 20 so as to be at least partly immersed in the solution 22.
  • An electromotive force 36 is applied between workpiece 10 and anode 34 with workpiece 10 connected so as to act as a cathode. In this manner, workpiece 10 is plated with nickel metal ions.
  • the plating action simultaneously entraps diamond particles 25 on the surface of workpiece 10 and the plated nickel metal 23 (see FIGURE 2) serves to mechanically bond diamond particles 25 to the etched surface of workpiece 10 as the particles 25 are individually embedded in the cavities 21 of the etched surface. It has been discovered that the imposition of an electromotive force 36 appears to cause an attraction between diamond particles 25 and workpiece 10 so as to more densely pack diamond particles 25 on the surface of workpiece 10. For example, approximately six minutes has been found satisfactory to form a single layer of 24 to 41 micron diamond.
  • the cavities 21 (FIGURE 2) created in workpiece 10 during the etching step greatly assist in forming a strong bond between workpiece 10 and the first diamond/nickel matrix 23.
  • Many of the diamond particles 25 are partially recessed into the cavities 21 so as to limit their exposure to the shear plane formed along the diamond/metal surface.
  • the diamonds 25 thus secured have surprising resistance to shear and breakage away from the workpiece 10.
  • workpiece 10 is removed from the plating bath and rinsed with water to remove any unplated residue from bath 20. While not essential, it has been found desirable to follow the rinsing step with an activation step wherein the diamond plated workpiece is treated by dipping or rinsing in a 50% hydrochloric acid solution prior to immersing the workpiece in a second plating bath 40. Surface activation is primarily used where the workpiece surface has been oxidised. If care is taken to avoid drying of the workpiece 10 during the etching and electroplating process, activation can usually be avoided. Prior to treatment in the second plating bath 40, the diamond adheres to the workpiece 10 as a soft pack.
  • the second plating bath 40 comprises an electroless plating solution 42 of metal ions.
  • the metal used may be nickel or any other suitable metal selected in accordance with the hardness and thickness characteristics desired in an intended application for workpiece 10.
  • Any suitable electroless plating solution could be used such as solutions marketed by the Allied Kelite Division of Richardson Chemical Co. (Product No. 794 A, B and HZ).
  • Tne workpiece is held in this electroless plating bath for sufficient time to achieve a suitable second coating of metal 27 (see FIGURE 2). For example, approximately 70 to 80 minutes has been found adequate for many intended applications.
  • the temperature in the electroless plating bath 40 is elevated to about 90°C or such other elevated temperature as may be recommended by the manufacturer of the solution.
  • electrolytic plating may be used.
  • Nickel plating has been found to deposit about 2 x 10 -5 m nickel per hour in this bath and it is presently preferred to substantially interfill the surface area around the diamonds 25 and/or cover the diamonds 25 adhering to the workpiece.
  • workpiece 10 After removal from the second or electroless plating bath 40, workpiece 10 is cleaned with water, dried and then subjected to heat treatment, in a furnace 43 wherein workpiece 10 is heated to approximately 315 0 C for approximately one hour. Heat treatment between 340°C and 400°C for one hour yields a workpiece having a Rockwell C-Scale hardness of 72. Hardness of 46 to 72 has been found desirable. The actual hardness achieved is a function of the type of metal plated on to workpiece 10 in the second plating bath 40 (which may be different to the metal plated in the first bath 20) and the temperature and firing time of the heat treatment step.
  • first plating bath shown in FIGURE 3 for electroplating diamond particles on to the etched surface of the workpiece 10 is similar to that described in connection with FIGURE 1 in that the or each workpiece 10 is at least partly embedded in a layer 46 of abrasive particles.
  • an enclosed box generally designated 41 is provided in the first plating bath 20.
  • the box 41 has sides 44 and a base 45.
  • Nickel anode 34 is placed in the bottom of box 41 and connected to an electromotive force 36 as described previously.
  • a port 48 permits plating solution 22 to enter the box 41.
  • port 48 may be used as an exit for plating solution 22 as hereinafter more fully described.
  • a porous platform 50 is supported by sides 44 of box 41.
  • a fine mesh net 52 is laid on top of porous platform 50 so as to prevent the diamond particles 46 from falling through the holes 54 of platform 50.
  • a second platform 56 covers the diamond particles 46.
  • Platform 56 has a plurality of openings 58 through which workpieceslO may extend so as to permit the etched portion of each workpiece 10 to be embedded into the layer 4G of diamond particles.
  • openings 58 are only large enough to permit a very small tolerance between each workpiece 10 and opening 58. This prevents diamond particles 46 from being carried out of the openings 58 during the plating process.
  • Each workpiece 10 is connected through a wire 60 of cable 62 to electromotive force 36.
  • plating solution 22 is drawn through port 48 into box 41.
  • plating solution 22 may be drawn through openings 58 and may exit through port 48.
  • Plating solution 22 may be circulated through box 41 by a pump (not shown), by convection currents, or by gravity flow.
  • the solution 22 and metal ions formed from anode 34 then arc passed through porous platform 50 and net 52, and through the layer of diamond particles 46.
  • Nickel or other metal is plated on to the workpiece 10 as the solution 22 circulates through box 41, and in this manner, diamond particles 25 may be uniformly plated into the cavities 21 (see FIGURE 2) etched into the surface of the workpiece 10 through the electrodeposition of metal on to the workpiece and around the particles 25.
  • the process of the present invention advantageously provides a stronger bond of diamond particles to the surface of a workpiece.
  • the second coating of metal plated on to the workpiece may be advantageously selected so as to provide a surface which will surprisingly enhance the wear of the workpiece by helping to prevent glazing of the cutting edge.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • ing And Chemical Polishing (AREA)
EP19790300429 1978-03-20 1979-03-19 Procédé de fixation pour outils abrasifs Expired EP0004449B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US05/888,081 US4155721A (en) 1974-11-06 1978-03-20 Bonding process for grinding tools
US888081 1978-03-20

Publications (3)

Publication Number Publication Date
EP0004449A2 true EP0004449A2 (fr) 1979-10-03
EP0004449A3 EP0004449A3 (en) 1979-11-14
EP0004449B1 EP0004449B1 (fr) 1981-12-30

Family

ID=25392489

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19790300429 Expired EP0004449B1 (fr) 1978-03-20 1979-03-19 Procédé de fixation pour outils abrasifs

Country Status (6)

Country Link
EP (1) EP0004449B1 (fr)
JP (1) JPS5921749B2 (fr)
AT (1) AT368053B (fr)
CA (1) CA1143692A (fr)
DE (1) DE2961643D1 (fr)
HK (1) HK92185A (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0129155A2 (fr) * 1983-06-20 1984-12-27 Luigi Pedrini Dispositif pour calibrer le granit, le marbre ou similaire en forme de plaque
GB2197335A (en) * 1986-11-14 1988-05-18 Peter Andrew Saville Abrasive tool
EP0633087A1 (fr) * 1993-07-07 1995-01-11 C. & E. FEIN GmbH & Co. Lame de scie pour scier les matériaux ferreux ductiles
EP1860211A2 (fr) * 2006-05-25 2007-11-28 SPX Corporation Composant de traitement alimentaire et son procédé de revêtement

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5863170B2 (ja) * 2011-01-31 2016-02-16 サンコール株式会社 固定砥粒ワイヤの製造方法
JP5824182B1 (ja) * 2015-06-29 2015-11-25 ジャスト株式会社 把持具の把持面のめっき処理方法及び把持具

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2360798A (en) * 1942-12-12 1944-10-17 Seligman Diamond-containing abrasive substance
DE752952C (de) * 1940-09-29 1951-08-16 Finzler Verfahren zur elektrolytischen Bindung hochwertiger Schleifmittel, z. B. Diamantkoerner, in Metall zwecks Herstellung von Schleifwerkzeugen
FR1147811A (fr) * 1956-04-20 1957-11-29 Procédé de fabrication de surfaces d'outils diamantées par électrolyse et produit obtenu
GB966604A (en) * 1960-03-14 1964-08-12 Karl Henry Mattsson Improvements in or relating to the production of wear-resistant surfaces of measuring tools or gauges
US3356599A (en) * 1964-07-20 1967-12-05 Shirley I Weiss Methods and apparatus for making annular cutting wheels
FR2075972A1 (fr) * 1970-01-07 1971-10-15 Kampschulte & Cie Dr W
FR2134846A5 (fr) * 1971-04-22 1972-12-08 Nasch Marguerite
GB1311854A (en) * 1969-07-17 1973-03-28 Atomic Energy Authority Uk Bearing surfaces formed of composite metal granule structures
US3957593A (en) * 1975-01-31 1976-05-18 Keene Corporation Method of forming an abrasive tool
US3973925A (en) * 1973-03-20 1976-08-10 Toshio Asaeda Manufacturing process for a metal bonded grinding tool and the metal bonded grinding tool produced thereby
US4079552A (en) * 1974-11-06 1978-03-21 Fletcher J Lawrence Diamond bonding process

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE752952C (de) * 1940-09-29 1951-08-16 Finzler Verfahren zur elektrolytischen Bindung hochwertiger Schleifmittel, z. B. Diamantkoerner, in Metall zwecks Herstellung von Schleifwerkzeugen
US2360798A (en) * 1942-12-12 1944-10-17 Seligman Diamond-containing abrasive substance
FR1147811A (fr) * 1956-04-20 1957-11-29 Procédé de fabrication de surfaces d'outils diamantées par électrolyse et produit obtenu
GB966604A (en) * 1960-03-14 1964-08-12 Karl Henry Mattsson Improvements in or relating to the production of wear-resistant surfaces of measuring tools or gauges
US3356599A (en) * 1964-07-20 1967-12-05 Shirley I Weiss Methods and apparatus for making annular cutting wheels
GB1311854A (en) * 1969-07-17 1973-03-28 Atomic Energy Authority Uk Bearing surfaces formed of composite metal granule structures
FR2075972A1 (fr) * 1970-01-07 1971-10-15 Kampschulte & Cie Dr W
FR2134846A5 (fr) * 1971-04-22 1972-12-08 Nasch Marguerite
US3973925A (en) * 1973-03-20 1976-08-10 Toshio Asaeda Manufacturing process for a metal bonded grinding tool and the metal bonded grinding tool produced thereby
US4079552A (en) * 1974-11-06 1978-03-21 Fletcher J Lawrence Diamond bonding process
US3957593A (en) * 1975-01-31 1976-05-18 Keene Corporation Method of forming an abrasive tool

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0129155A2 (fr) * 1983-06-20 1984-12-27 Luigi Pedrini Dispositif pour calibrer le granit, le marbre ou similaire en forme de plaque
EP0129155A3 (fr) * 1983-06-20 1986-10-08 Luigi Pedrini Dispositif pour calibrer le granit, le marbre ou similaire en forme de plaque
GB2197335A (en) * 1986-11-14 1988-05-18 Peter Andrew Saville Abrasive tool
EP0633087A1 (fr) * 1993-07-07 1995-01-11 C. & E. FEIN GmbH & Co. Lame de scie pour scier les matériaux ferreux ductiles
US5544643A (en) * 1993-07-07 1996-08-13 C&E Fein, Gmbh & Co. Method for saving ductile from material having a concrete lining
EP1860211A2 (fr) * 2006-05-25 2007-11-28 SPX Corporation Composant de traitement alimentaire et son procédé de revêtement
EP1860211A3 (fr) * 2006-05-25 2010-07-28 SPX Corporation Composant de traitement alimentaire et son procédé de revêtement

Also Published As

Publication number Publication date
AT368053B (de) 1982-09-10
EP0004449A3 (en) 1979-11-14
EP0004449B1 (fr) 1981-12-30
JPS54132892A (en) 1979-10-16
ATA200579A (de) 1982-01-15
DE2961643D1 (en) 1982-02-18
JPS5921749B2 (ja) 1984-05-22
CA1143692A (fr) 1983-03-29
HK92185A (en) 1985-11-29

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