Refractory metal plates with improved uniformity of texture
View Patent ↗A refractory metal plate is provided. The plate has a center, a thickness, an edge, a top surface and a bottom surface, and has a crystallographic texture (as characterized by through thickness gradient, banding severity; and variation across the plate, for each of the texture components 100//ND and 111//ND, which is substantially uniform throughout the plate.
1. A refractory metal plate having a center, a thickness, en edge, a top surface and a bottom surface, the refractory metal plate having a crystallographic texture as characterized by
through thickness gradient;
banding severity; and
variation across the plate,
for the texture components 100//ND and 111//ND using electron back-scatter diffraction with a 15 μm step in both the horizontal and vertical directions for each measurement,
wherein the maximum through-thickness gradient is less than or equal to 13% per mm, the maximum banding severity is less than or equal to 8%, and the maximum variation across the plate is lass than or equal to 11%;
wherein the metal plate is at least 99.95% pure refractory metal; and
wherein the metal plate has a grain size that is less than 60 μm.
2. The refractory metal plate of claim 1 , wherein the refractory metal plate is manufactured by ingot metallurgy, and the maximum through-thickness gradient is less than or equal to 9% per mm.
3. The refractory metal plate of claim 2 , wherein the maximum through-thickness gradient is less than or equal to 8% per mm.
4. The refractory metal plate of claim 3 , wherein the texture is determined from grains maps with grains separately identified for 100 and 111 within 15° of the normal direction.
5. The refractory metal plate of claim 3 , wherein the refractory metal plate is manufactured by powder metallurgy, and the metal plate is a sputtering target.
6. The refractory metal plate of claim 5 , wherein the maximum variation across the plate is less than or equal to 7% and the average variation across the plate is less than or equal to 4% for the texture components 100//ND and 111//ND.
7. The refractory metal Mate of claim 5 , wherein the average through-thickness gradient is less than or equal to 5% per mm for the texture components 100//ND and 111//ND, and the average banding severity is less than 5% for the texture components 100//ND and 111//ND.
8. The refractory metal plate of claim 5 , wherein the average through-thickness gradient is less than 2% per mm for the texture components 100//ND and 111//ND.
9. The refractory metal plate of claim 5 , wherein the maximum through thickness gradient is less than 3%, and the maximum banding severity is less than 5% for the texture components 100//ND and 111//ND.
10. The refractory metal plate of clalm 1 , wherein the metal plate is manufactured by ingot metallurgy, and the metal plate is a sputtering target.
11. The refractory metal plate of claim 10 , wherein the average through-thickness gradient is less than or equal to 4% per mm for the texture components 100// ND and 111//ND.
12. The refractory metal plate of claim 10 , wherein the average banding severity is less than or equal to 6% for the texture components 100//ND and 111//ND.
13. The refractory metal plate of claim 12 wherein a population of the metal plates has banding severity values with a standard deviation of less than 4.
14. The refractory metal plate of claim 10 , wherein the average variation across the plate is less than or equal to 6% for the texture components 100//ND and 111//ND.
15. The refractory metal plate of claim 10 , wherein the maximum through-thickness gradient is less than 8% per mm for the texture components 100//ND and 111//ND; and the maximum variation across the plate is less than 7% for the texture components 100//ND and 111//ND.
16. The refractory metal plate of claim 10 , whereln the average through-thickness gradient for the texture component 111//ND is less than or equal to 2% per mm.
17. The refractory meta plate of claim 1 , wherein the refractory metal is tantalum.
18. The refractory metal plate of claim 1 wherein the refractory metal is niobium.
19. The refractory metal plate of claim 18 , wherein the metal plate least 99.995%pure factory metal.
20. The refractory metal plate of claim 1 , wherein the plate is manufactured by ingot metallurgy, the plate is manufactured using a process including rolling the plate asymmatricaliy so that the platy has a texture as characterized by through-thickness gradient for the texture components 100//ND and 111//ND, where the average through-thickness gradient is less than or equal to 4% per mm.
21. The refractory metal plate of claim 1 , wherein the plate is manufactured by powder metallurgy, the plate is manufactured using a process including rolling the plate asymmetrically, wherein the asymmetric rolling is carded out on an inclined plane having an angle of incline between 2 and 20 degrees so that the plate has a texture as characterized by through-thickness gradient, where the average through-thickness gradient for the texture components 100//ND and 111//ND is less than or equal to 2% per mm.
22. The refractory metal plate of claim 1 , wherein a population of the metal plates has banding severity values with a standard deviation of less than 4.
23. The refractory metal plate of claim 1 , wherein the texture is determined from grains maps with grains separately identified for 100 and 111 within 15° of the normal direction.