Coextrusion fabrication method
A method of forming a composite article by injecting at least two composite materials comprising metal carbides into a mold to form a green compact is disclosed. The composite materials may be metal powders comprising a binder metal, a hard particle. The composite material may further comprise a plastic binder. The two different composite materials are injected into the mold to form the green compact. Additionally, the composite materials may be injected through a die before entering the mold. In a specific embodiment, the die forms at least one internal channel within the green compact.
1. A method of forming an article, the method comprising:
coextruding at least two composite material powders comprising metal carbides to form an extruded green compact having at least two regions, wherein at least one of the composite material powders includes greater than zero to less than 5 weight percent cubic carbides, and
forming at least one internal channel within the extruded green compact intersecting at least two regions of the extruded green compact.
2. The method of claim 1 , wherein the at least one of the composite material powders includes greater than zero to less than 3 weight percent cubic carbides.
3. The method of claim 1 , wherein the at least two composite material powders comprise a first composite material powder and a second composite material powder, wherein the composition of the first composite material powder differs from the composition of the second composite material powder.
4. The method of claim 1 , wherein the at least two composite material powders individually comprise a metal carbide and a binder.
5. The method of claim 1 comprising coextruding at least two composite material powders through at least one of a funnel and a die.
6. The method of claim 5 , wherein coextruding at least two composite material powders comprises pumping a first composite material powder through a first portion of the funnel, and pumping a second composite material powder through a second portion of the funnel, wherein the two composite material powders exit the funnel in intimate contact with each other.
7. The method of claim 5 , wherein the at least one of a funnel and a die comprises at least one element to form the at least one internal channel within the extruded green compact.
8. The method of claim 5 , wherein the at least one of a funnel and a die comprises at least one wire to form the at least one internal channel within the extruded green compact.
9. The method of claim 1 , wherein the at least two regions of the extruded green compact differ in at least one characteristic.
10. The method of claim 1 , wherein the at least one internal channel in the extruded green compact intersects an outer region of the extruded green compact and a core region of the extruded green compact.
11. The method of claim 5 , wherein the at least one of a funnel and a die comprises at least two wires, wherein each wire forms an internal channel within the extruded green compact.
12. The method of claim 5 , wherein the at least one of a funnel and a die comprises internal spiral serrations.
13. The method of claim 5 wherein the at least one of a funnel and a die comprises a rotating die.
14. The method of claim 5 , wherein the at least one of a funnel and a die comprises a channel die.
15. The method of claim 1 comprising loading a feed chamber of a coextruder with the at least two composite material powders.
16. The method of claim 1 , wherein the extruded green compact comprises a first composite material powder and a second composite material powder, and the composite material powders are coaxially disposed.
17. The method of claim 1 , wherein the extruded green compact comprises at least an outer region and a coaxially disposed core region, wherein the outer region comprises the first composite material powder, the core region comprises the second composite material powder, and the first composite material powder differs from the second composite material powder in at least one characteristic.
18. The method of claim 1 , wherein the extruded green compact comprises at least one helical channel.
19. The method of claim 1 , wherein the extruded green compact comprises two channels.
20. The method of claim 1 , wherein the method comprises coextruding three composite material powders comprising metal carbides to form the extruded green compact, wherein at least one of the composite material powders includes greater than zero to less than 5 weight percent cubic carbides.
21. The method of claim 20 , wherein the extruded green compact comprises an outer region comprising the first composite material powder, a first inner region comprising the second composite material powder, and a second inner region comprising the third composite material powder.
22. The method of claim 20 , wherein the extruded green compact comprises a tip comprising the first composite material powder, an inner region comprising the second composite material powder, and an outer region comprising the third composite material powder.
23. The method of claim 20 wherein the first composite material powder, the second composite material powder, and the third composite material powder are cemented carbide powders, each cemented carbide powder individually comprising a metal carbide and a binder.
24. The method of claim 1 , wherein the first composite material powder and the second composite material powder are cemented carbide powders, each cemented carbide powder individually comprising a metal carbide and a binder.
25. The method of claim 1 , wherein the article is selected from a rotary cutting tool blank, a rotary cutting tool, and a rod.
26. The method of claim 1 , wherein the article is a rotary cutting tool selected from a drill, an end mill, a reaming tool, a countersinking tool, a counterboring tool, and a tapping tool.
27. The method of claim 1 , wherein the article is an elongate generally cylindrical article.
28. A method of forming an article, the method comprising:
providing two composite material powders comprising metal carbides, wherein at least one composite material powder includes greater than zero to less than 5 weight percent cubic carbides, and
coextruding the at least two composite material powders to form an extruded green compact,
wherein the composite material powders are in individually extruded forms prior to coextruding.
29. The method of claim 28 , wherein the extruded forms prior to coextruding is one of a rod, a tube, a bar, and a strip.
30. The method of claim 28 , wherein the extruded forms prior to coextruding have a shape that is one of a rectangle, a gear profile, and a star shape.
31. The method of claim 28 comprising loading a feed chamber of a coextruder with the at least two composite material powders.
32. The method of claim 31 , wherein loading the feed chamber comprises loading a first composite material powder in the form of an extruded rod into the feed chamber.
33. The method of claim 32 , wherein the extruded rod is formed by individually extruding the first composite material powder directly into the feed chamber.
34. The method of claim 32 , wherein loading the feed chamber comprises loading a second composite material powder in the form of an extruded tube into the feed chamber.
35. The method of claim 34 , wherein the extruded tube is individually extruded directly into the feed chamber.
36. The method of claim 28 , wherein a first extruded form is an extruded rod and a second extruded form is an extruded tube.
37. The method of claim 36 , wherein the extruded rod is disposed in the extruded tube prior to coextruding the extruded forms.
38. The method of claim 28 , wherein the composition of a first composite material powder differs from the composition of a second composite material powder.
39. The method of claim 28 , wherein the first and second composite material powders include a binder.
40. The method of claim 28 , wherein the first composite material powder and the second composite material powder are cemented carbide powders, each cemented carbide powder individually comprising a metal carbide and a binder.
41. The method of claim 28 , wherein the at least two composite material powders are coextruded through at least one of a funnel and a die.
42. The method of claim 41 , wherein the at least one of a funnel and a die comprises internal spiral serrations.
43. The method of claim 28 , wherein the extruded green compact includes an internal channel.
44. The method of claim 28 , wherein the at least one composite material powder includes greater than zero to less than 3 weight percent cubic carbides.
45. The method of claim 28 , wherein the article is selected from a rotary cutting tool blank, a rotary cutting tool, and a rod.
46. The method of claim 28 , wherein the article is a rotary cutting tool selected from a drill, an end mill, a reaming tool, a countersinking tool, a counterboring tool, and a tapping tool.
47. The method of claim 28 , wherein the article is an elongate generally cylindrical article.