# US 8,540,785 B2 · Bonded abrasive tool and method of forming > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,785 B2 - Document ID: US8540785B2 - Status: Granted - Kind: B2 - Application number: 13/570,134 - Filed: 2012-08-08 - Published: 2012-11-29 - Granted: 2013-09-24 - Earliest claimed: 2008-12-30 - Assignees: Saint-Gobain Abrasives, Inc.; Saint-Gobain Abrasifs - Applicants: Konstantin S. Zuyev; Walter Strandgaard; Joel A. Fife; Muthu Jeevanantham - Inventors: Konstantin S. Zuyev; Walter Strandgaard; Joel A. Fife; Muthu Jeevanantham - Web page: https://patentgrep.com/patent/US8540785B2 ## CPC - B24D 3/32: for porous or cellular structure - B24D: TOOLS FOR GRINDING, BUFFING OR SHARPENING (abrading-bodies specially designed for tumbling apparatus, e.g. abrading-balls B24B31/14; honing tools B24B33/08; lapping tools B24B37/11) ## Abstract A bonded abrasive tool includes a bonded abrasive body having a bond matrix material including an organic bond material, abrasive grains contained within the bond matrix material, and chopped fiber bundles within the bond matrix material. The tool further has a porosity within the bonded abrasive body, wherein a majority of the porosity includes pores surrounding the chopped fiber bundles. ## Claims ### Claim 1 A bonded abrasive tool comprising: a bonded abrasive body comprising: a bond matrix material comprising an organic bond material; abrasive grains contained within the bond matrix material; chopped fiber bundles within the bond matrix; and porosity within the bonded abrasive body, wherein the porosity comprises two phases, a first phase comprising small pores uniformly dispersed within the bond matrix material, and a second phase comprising large pores selectively disposed around the chopped fiber bundles. ### Claim 2 (depends on 1) The bonded abrasive tool of claim 1, wherein the large pores are voids extending laterally around portions of the peripheral surfaces of the chopped fiber bundles. ### Claim 3 (depends on 1) The bonded abrasive tool of claim 1, wherein the large pores are voids extending longitudinally along a portion of the length of the chopped fiber bundles. ### Claim 4 (depends on 1) The bonded abrasive tool of claim 1, wherein the large pores comprise irregular cross-sectional shapes. ### Claim 5 (depends on 1) The bonded abrasive tool of claim 1, wherein the small pores comprise a circular cross-sectional shape. ### Claim 6 (depends on 1) The bonded abrasive tool of claim 1, wherein the large pores have an average pore size (P1) and the small pores have an average pore size (Ps), and the bonded abrasive body comprises a pore size ratio between the average size of the large pores and the small pores (P1:Ps) of at least about 2:1. ### Claim 7 (depends on 6) The bonded abrasive tool of claim 6, wherein the pore size ratio (P1:Ps) is within a range between about 2:1 and about 10:1. ### Claim 8 (depends on 1) The bonded abrasive tool of claim 1, wherein the large pores have an average pore size (P1) within a range between about 1 mm and about 10 mm. ### Claim 9 (depends on 1) The bonded abrasive tool of claim 1, wherein the small pores have an average pore size (Ps) of not greater than about 1 mm. ### Claim 10 (depends on 1) The bonded abrasive tool of claim 1, wherein the bonded abrasive body comprises not greater than about 12 vol % porosity. ### Claim 11 (depends on 1) The bonded abrasive tool of claim 1, wherein at least about 75 vol % and not greater than about 98 vol % of the total volume of porosity is large pores. ### Claim 12 (depends on 1) The bonded abrasive tool of claim 1, wherein a majority of the porosity comprises pores surrounding the chopped fiber bundles. ### Claim 13 A bonded abrasive tool comprising: a bonded abrasive body comprising: a bond matrix material comprising an organic bond material; abrasive grains contained within the bond matrix material; chopped fiber bundles within the bond matrix having a length within a range between about 1 mm and about 5 mm; and porosity within the bonded abrasive body, wherein the porosity comprises two phases, a first phase comprising small pores having circular cross-sectional shapes uniformly dispersed within the bond matrix material, and a second phase comprising large pores extending laterally around portions of the peripheral surfaces of the chopped fiber bundles. ### Claim 14 (depends on 13) The bonded abrasive tool of claim 13, wherein the bonded abrasive body comprises a fracture toughness within a range between about 750 J/mm2 and about 1100 J/mm2. ### Claim 15 (depends on 13) The bonded abrasive tool of claim 13, wherein the chopped fiber bundles comprise a length (l), a width (w), and an aspect ratio (l:w) defined by the length and the width of at least about 2:1. ### Claim 16 (depends on 13) The bonded abrasive tool of claim 13, wherein chopped fiber bundles comprise at least about 200 fibers bonded together with an organic binder. ### Claim 17 (depends on 13) The bonded abrasive tool of claim 13, wherein the chopped fiber bundles comprise a glass material. ### Claim 18 A bonded abrasive tool comprising: a bonded abrasive body comprising: a bond matrix material comprising an organic bond material; abrasive grains contained within the bond matrix material; chopped fiber bundles within the bond matrix; and porosity within the bonded abrasive body, wherein the porosity comprises two phases, a first phase comprising small pores uniformly dispersed within the bond matrix material, and a second phase comprising large pores surrounding the chopped fiber bundles, the bonded abrasive body demonstrating a material removal rate (MMR) of at least about 13 in3/min and having a G-ratio (MMR/WWR) of not greater than about 40 while grinding a metal workpiece having a thickness of 0.5 inches with a downforce applied to the bonded abrasive body of at least about 45 HP. ### Claim 19 (depends on 18) The bonded abrasive tool of claim 18, wherein the MRR is within a range between about 13 in3/min and about 17 in3/min. ### Claim 20 (depends on 18) The bonded abrasive tool of claim 18, wherein G-ratio is within a range between about 25 and about 40.