Bonded abrasive article and method of grinding

• US 9,278,431 B2
• Filed: 12/30/2013
• Issued: 03/08/2016
• Est. Priority Date: 12/31/2012
• Status: Active Grant

• Current Assignee: Saint-Gobain Abrasives Incorporated (Compagnie De Saint-Gobain), Saint-Gobain Abrasifs (Compagnie de Saint-Gobain SA)
• Original Assignee: Saint-Gobain Abrasives Incorporated (Compagnie De Saint-Gobain), Saint-Gobain Abrasifs (Compagnie de Saint-Gobain SA)
• Inventors: Ramanath, Srinivasan, Saucier, Kenneth A., Upadhyay, Rachana, Wang, Cong
• Primary Examiner(s): Morgan, Eileen
• Application Number:
  US14/143,260
• Publication Number:
  US 20140187123A1
• Time in Patent Office: 799 Days
• Field of Search: 451/9, 451/10, 451/11, 451/28, 451/41, 451/44, 451/56, 451/63, 451/533, 451/541, 451/548, 513/09
• US Class Current: 1/1
• CPC Class Codes: B24B 1/00 Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
• CPC Class Codes: B24B 9/00 Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor B24B21/00 takes precedence; for sharpening cutting edges on tools B24B3/00; removing burrs by loose abrasive material B24B31/00
• CPC Class Codes: B24D 3/008 Abrasive bodies without external bonding agent
• CPC Class Codes: B24D 3/06 metallic or mixture of metals with ceramic materials, e.g. hard metals, "cermets", cements
• CPC Class Codes: B24D 3/342 incorporated in the bonding agent
• CPC Class Codes: B24D 5/00 Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor

Abstract

An abrasive article configured to grind a workpiece having a fracture toughness of less than about 6 MPa·m ½ includes a body comprising abrasive particles contained within a bond material comprising a metal, wherein the body comprises a ratio of V_AG/V_BM of at least about 1.3, wherein V_AG is a volume percent of abrasive particles within a total volume of the body and V_BM is a volume percent of bond material within the total volume of the body, and wherein the abrasive particles have an average particle size of 1 to 45 microns.

Claims

1. An abrasive article configured to grind a silicon nitride workpiece having a fracture toughness of less than about 6 MPa·

m^0.5, the abrasive article comprising;

a body comprising abrasive particles contained within a bond material comprising a metal, wherein the body comprises a ratio of V_AG/V_BM of at least about 1.3, wherein V_AG is a volume percent of abrasive particles within a total volume of the body and V_BM is a volume percent of bond material within the total volume of the body,

wherein the abrasive particles have an average particle size of about 1 to about 45 microns;

wherein during a periphery insert grinding test operation of the abrasive article on at least one edge of the silicon nitride workpiece, the edge of the silicon nitride workpiece has a maximum chip size of less than about 0.0025 inches and the maximum chip size is at least 8% less than the maximum chip size achieved during a periphery insert grinding test operation of a conventional metal-bonded abrasive article on the at least one edge of the silicon nitride workpiece; and

wherein the periphery insert grinding test operation is conducted at a rough feed rate of 2 inches/min and a finish feed rate of 1.0 inches/min with the abrasive article operating at 8500 SFPM and a cut depth of 0.025 inches.

2. The abrasive article of claim 1, wherein the bond material comprises at least 1 vol % of an active bond composition of the total volume of the bond material.

3. The abrasive article of claim 2, wherein the active bond composition comprises a compound including a metal or metal alloy.

4. The abrasive article of claim 2, wherein the active bond composition comprises a metal element selected from the group of metal elements consisting of titanium, vanadium, chromium, zirconium, hafnium, tungsten, and a combination thereof.

5. The abrasive article of claim 2, wherein the active bond composition comprises a compound selected from the group consisting of carbides, nitrides, oxides, and a combination thereof.

6. The abrasive article of claim 2, wherein the active bond composition is disposed at an interface of the abrasive particles and the bond material.

7. The abrasive article of claim 1, wherein the bond material comprises at least one transition metal element.

8. The abrasive article of claim 1, wherein the bond material comprises a metal selected from the group of metals consisting of copper, tin, silver, molybdenum, zinc, tungsten, iron, nickel, antimony, and a combination thereof.

9. The abrasive article of claim 1, wherein the bond material comprises a metal alloy including copper and tin.

10. The abrasive article of claim 1, wherein the ratio of V_AG/V_BM is at least about 1.5.

11. The abrasive article of claim 1, wherein the bond material comprises an average fracture toughness (K_1c) of not greater about 4.0 MPa m^0.5.

12. The abrasive article of claim 1, wherein the bond material comprises an average fracture toughness (K_1c) within a range between about 0.6 MPa m^0.5 and about 4.0 MPa m^0.5.

13. The abrasive article of claim 1, wherein the active bond composition is present in an amount within a range between about 1 vol % and about 40 vol % of the total volume of the bond material.

14. The abrasive article of claim 1, wherein the body comprises at least about 5 vol % porosity of the total volume of the body.

15. The abrasive article of claim 1, wherein the body comprises a ratio of V_P/V_BM of at least about 1.5, wherein V_p is a volume percent of particulate material including abrasive grains and fillers within a total volume of the body and V_BM is a volume percent of bond material within the total volume of the body.

16. The abrasive article of claim 1, wherein the abrasive article exhibits a material removal rate of at least about 1.0 in³/min/in [10 mm³/sec/mm] on a silicon nitride workpiece.

17. The abrasive article of claim 1, wherein the abrasive article exhibits a feed rate of at least about 0.5 inches/min with a silicon nitride workpiece.

18. A method of removing material from a silicon nitride workpiece comprising:

providing a workpiece having a fracture toughness of less than about 6 MPa·

.m^0.5; and

removing material from at least an edge of the workpiece with an abrasive article, wherein the abrasive article comprises a body comprising abrasive particles contained within a bond material comprising a metal, wherein the body comprises a ratio of V_AG/V_BM of at least about 1.3, wherein V_AG is a volume percent of abrasive particles within a total volume of the body and V_BM is a volume percent of bond material within the total volume of the body,

wherein the abrasive particles have an average particle size of 1 to 45 microns;

wherein during a periphery insert grinding test operation of the abrasive article on at least one edge of the silicon nitride workpiece, the edge of the silicon nitride workpiece has a maximum chip size of less than about 0.0025 inches and the maximum chip size is at least 8% less than the maximum chip size achieved during a periphery insert grinding test operation of a conventional metal-bonded abrasive article on the at least one edge of the silicon nitride workpiece; and

wherein the periphery insert grinding test operation is conducted at a rough feed rate of 2 inches/min and a finish feed rate of 1.0 inches/min with the abrasive article operating at 8500 SFPM and a cut depth of 0.025 inches.