Abrasive tool inserts with diminished residual tensile stresses and their production

1. An abrasive tool insert, which comprises:

(a) a substrate having a support face that includes:

(1) an inner support table, wherein the inner support table comprises at least one of; a series of concentric grooves, a series of outwardly radiating channels, a series of intersecting channels, a series of outwardly radiating ridges, and a series of substantially parallel raised ridges that extend from said support table;

(2) an outer shoulder having a width, S w ,

(3) a downwardly sloping interface from said support table to said shoulder which interface has a slope angle, S a ; and

(b) a continuous abrasive layer integrally formed on said substrate support face, which abrasive layer includes:

(1) a center having a height, D c ,

(2) a diameter, D d ,

(3) a periphery having a height, D p , in contact with said shoulder and which periphery forms a cutting edge;

wherein,

S w :D d ranges between about 0.01 and about 0.5; and

for each S a and S w :D d ,D c :D p is selected so as to diminish residual stress in the abrasive layer.

2. The abrasive tool insert of claim 1 , wherein said substrate comprises cemented metal carbide.

3. The abrasive tool insert of claim 2 , wherein said cemented metal carbide is selected from the group consisting essentially of Group IVB, Group VB, and Group VIB metal carbides.

4. The abrasive tool insert of claim 1 , wherein said abrasive layer is selected from the group consisting essentially of diamond, cubic boron nitride, wurtzite boron nitride, and combinations thereof.

5. The abrasive tool insert of claim 3 , wherein said abrasive layer is selected from the group consisting essentially of diamond, cubic boron nitride, wurtzite boron nitride, and combinations thereof.

6. The abrasive tool insert of claim 1 , wherein said S a and D c :D p each has a value corresponding to one of:

for S a ranging between about 20° and 30°, D c :D p ranging from between about 0.25 and 0.85;

for S a ranging between about 20° and 30°, D c :D p ranging from between about 0.35 and 0.75;

for S a ranging between about 20° and 30°, D c :D p ranging from between about 0.45 and 0.65;

for S a ranging between about 20° and 30°, D c :D p ranging from between about 0.5 and 0.55;

for S a ranging between about 25° and 35°, D c :D p ranging from between about 0.25 and 0.8;

for S a ranging between about 25° and 35°, D c :D p ranging from between about 0.3 and 0.7;

for S a ranging between about 25° and 35°, D c :D p ranging from between about 0.4 and 0.6,

for S a ranging between about 25° and 35°, D c :D p ranging from between about 0.45 and 0.55,

for S a ranging between about 30° and 40°, D c :D p ranging from between about 0.25 and 0.8;

for S a ranging between about 30° and 40°, D c :D p ranges from between about 0.25 and 0.7;

for S a ranging between about 30° and 40°, D c :D p ranging from between about 0.35 and 0.6;

for S a ranging between about 30° and 40°, D c :D p ranging from between about 0.45 and 0.5;

for S a ranging between about 35° and 45°, D c :D p ranging from between about 0.15 and 0.75;

for S a ranging between about 35° and 45°, D c :D p ranging from between about 0.25 and 0.65;

for S a ranging between about 35° and 45°, D c :D p ranging from between about 0.35 and 0.55,

for S a ranging between about 35° and 45°, D c :D p ranging from between about 0.4 and 0.5,

for S a ranging between about 40° and 50°, D c :D p ranging from between about 0.1 and 0.8;

for S a ranging between about 40° and 50°, D c :D p ranging from between about 0.2 and 0.7;

for S a ranging between about 40° and 50°, D c :D p ranging from between about 0.3 and 0.6;

for S a ranging between about 40° and 50°, D c :D p ranging from between about 0.4 and 0.5;

for S a ranging between about 45° and 55°, D c :D p ranging from between about 0.1 and 0.75;

for S a ranging between about 45° and 55°, D c :D p ranging from between about 0.2 and 0.7;

for S a ranging between about 45° and 55°, D c :D p ranging from between about 0.3 and 0.6;

for S a ranging between about 45° and 33°, D c :D p ranging from between about 0.4 and 0.5;

for S a ranging between about 50° and 60°, D c :D p ranging from between about 0.05 and 0.75;

for S a ranging between about 50° and 60°, D c :D p ranging from between about 0.15 and 0.65;

for S a ranging between about 50° and 60°, D c :D p ranging from between about 0.25 and 0.55;

for S a ranging between about 50° and 60°, D c :D p ranging from between about 0.35 and 0.45;

for S a ranging between about 35° and 65°, D c :D p ranging from between about 0.05 and 0.7;

for S a ranging between about 55° and 65°, D c :D p ranging from between about 0.1 and 0.6;

for S a ranging between about 55° and 65°, D c :D p ranging from between about 0.2 and 0.5;

for S a ranging between about 55° and 65°, D c :D p ranging from between about 0.3 and 0.4.

7. The abrasive tool insert of claim 6 , wherein for S a ranging between about 20° and 65°, D c :D p ranges from between about 0.1 and 0.8 and S w :D d ranges from about 0.01 to about 0.5.

8. The abrasive tool insert of claim 6 , wherein S w :D d ranges from about 0.01 to about 0.4.

9. The abrasive tool insert of claim 6 , wherein S w :D d ranges from about 0.01 to about 0.3.

10. The abrasive tool insert of claim 6 , wherein S w :D d ranges from about 0.01 to about 0.2.

11. The abrasive tool insert of claim 6 , wherein S w :D d ranges from about 0.01 to about 0.1.

12. The abrasive tool insert of claim 1 , wherein said sloping interface is curved.

13. An abrasive tool insert, which comprises:

(a) a cylindrical substrate having a support face that ranges from about 6 to about 30 mm in diameter and that includes:

(1) an innersupport table, wherein the inner support table comprises at least one of: a series of concentric grooves, a series of outwardly radiating channels, a series of intersecting channels, a series of outwardly radiating ridges, and a series of substantially parallel raised ridges that extend from said support table,

(2) an outer shoulder having a width, S w ,

(3) a downwardly sloping interface from said support table to said shoulder which interface has a slope angle, S a ; and

(b) a continuous abrasive layer integrally formed on said substrate support face, which abrasive layer includes:

(1) a center having a height, D c ,

(2) a diameter, D d , which ranges from about 6 to about 30 mm in diameter,

(3) a periphery having a height, D p , that ranges front about 2 to 6 mm and is in contact with said shoulder and which periphery forms a cutting edge;

wherein,

S w :D d ranges between about 0.01 and about 0.5; and

for each S a and S w :D d , D e :D p is selected so as to diminish residual stress in the abrasive layer.

14. The abrasive tool insert of claim 13 , wherein S w ranges from about 0.003 to about 0.083 mm.

15. The abrasive tool insert of claim 14 , wherein said substrate comprises cemented metal carbide.

16. The abrasive tool insert of claim 15 , wherein said cemented metal carbide is selected from the group consisting essentially of Group IVB, Group VB, and Group VIB metal carbides.

17. The abrasive tool insert of claim 13 , wherein said abrasive layer is selected from the group consisting essentially of diamond, cubic boron nitride, wurtzite boron nitride, and combinations thereof.

18. The abrasive tool insert of claim 13 , wherein S a ranges from about 40° to about 50° and said D c :D p ranges from about 0.1 to about 0.8.