Hot isostatic pressing (HIP) fabrication of multi-metallic components for pressure-controlling equipment

1. A multi-metallic ram for a blowout preventer (BOP), the multi-metallic ram comprising:

a first portion formed from a first metal alloy;

a second portion formed from a second metal alloy;

a metal boundary layer present along an interface between the first metal alloy and the second metal alloy to enable the first metal alloy to form opposed exterior surfaces of a first section of the multi-metallic ram, and to enable the second metal alloy to form an interior in the first section between the opposed exterior surfaces of the first section of the multi-metallic ram, wherein the second metal alloy defines an outer surface of a second section of the multi-metallic ram; and

a diffusion bond at the interface between the first metal alloy and the second metal alloy that joins the first metal alloy to the second metal alloy within the multi-metallic ram.

2. The multi-metallic ram of claim 1 , wherein the first metal alloy and the second metal alloy are independently selected from the group consisting of: chromium-molybdenum (Cr—Mo) steels, chromium-nickel-molybdenum (Cr—Ni—Mo) steels, maraging steels, super martensitic stainless steels, precipitation-hardened nickel alloys, precipitation-hardened martensitic steels, solution-annealed nickel alloys, tool steels, cobalt-bound tungsten-carbides, nickel-bound tungsten-carbides, nickel-cobalt (Ni—Co) alloys, and cobalt-chromium (Co—Cr) alloys.

3. The multi-metallic ram of claim 1 , wherein the diffusion bond has a thickness of 1 millimeter or less, and there is no substantial mixing of the first metal alloy and the second metal alloy outside of the diffusion bond.

4. The multi-metallic ram of claim 1 , wherein a grain structure of the first metal alloy and of the second metal alloy is substantially homogenous near the diffusion bond.

5. The multi-metallic ram of claim 1 , wherein the interface between the first metal alloy and the second metal alloy is planar.

6. The multi-metallic ram of claim 1 , wherein the interface between the first metal alloy and the second metal alloy is curved.

7. The multi-metallic ram of claim 1 , wherein the interface between the first metal alloy and the second metal alloy has contours that correspond to non-planar features disposed on an outer surface of the multi-metallic ram.

8. The multi-metallic ram of claim 1 , wherein each of the opposed exterior surfaces formed from the first metal alloy has a thickness greater than about 3 millimeters.

9. The multi-metallic ram of claim 1 , wherein the multi-metallic ram is devoid of welds between the first metal alloy and the second metal alloy.

10. A multi-metallic ram for a blowout preventer (BOP), comprising:

a blade section formed from a first metal alloy;

a body section formed from a second metal alloy;

a metal boundary layer present along an interface between the first metal alloy and the second metal alloy to enable the first metal alloy to form opposed exterior surfaces of a first section of the multi-metallic ram, and to enable the second metal alloy to form an interior in the first section between the opposed exterior surfaces of the first section of the multi-metallic ram, wherein the second metal alloy defines an outer surface of a second section of the mulit-metallic ram; and

a diffusion bond disposed at the interface between the first metal alloy and the second metal alloy that joins the first metal alloy to the second metal alloy within the multi-metallic ram.

11. The multi-metallic ram of claim 10 , wherein the blade section has a tensile strength, a yield strength, or a combination thereof, that is at least 5 percent greater than that of the body section of the multi-metallic ram.

12. The multi-metallic ram of claim 11 , wherein the tensile strength, the yield strength, or a combination thereof, of the blade section is at least 200 percent greater than that of the body section of the multi-metallic ram.

13. The multi-metallic ram of claim 10 , wherein the body section has a percent elongation or a percent reduction in area at least 5 percent greater than that of the blade section of the multi-metallic ram.

14. The multi-metallic ram of claim 10 , wherein the body section comprises a region formed from a third metal alloy, and the multi-metallic ram comprises a second diffusion bond disposed along a respective interface between the second metal alloy and the third metal alloy that joins the second metal alloy to the third metal alloy within the multi-metallic ram.

15. The multi-metallic ram of claim 14 , wherein the region comprises a seal region of the multi-metallic ram configured to contact an elastomer seal, and the third metal alloy has a higher corrosion resistance than the second metal alloy.

16. The multi-metallic ram of claim 14 , wherein the region comprises a slide region of the multi-metallic ram configured to contact and slide against another metal component of the BOP during operation, and the third metal alloy has a hardness that is at least 5 percent greater than that of the second metal alloy.

17. A multi-metallic ram for a blowout preventer (BOP), the multi-metallic ram comprising:

a blade portion formed from a first metal alloy;

a body portion formed from a second metal alloy and coupled to the first portion;

a metal boundary layer present along an interface between the first metal alloy and the second metal alloy to enable the first metal alloy to form opposed exterior surfaces of a first section of the multi-metallic ram, and to enable the second metal alloy to form an interior in the first section between the opposed exterior surfaces of the first section of the multi-metallic ram, wherein the second metal alloy defines an outer surface of a second section of the multi-metallic ram; and

wherein the interface that joins the first metal alloy to the second metal alloy within the multi-metallic ram is devoid of welds.