Cemented carbide containing tungsten carbide and fine grained iron alloy binder

Patent metadata

Field	Value
Publication number	US-11725262-B2
Application number	US-202217886949-A
Country	US
Kind code	B2
Filing date	Aug 12, 2022
Priority date	Nov 10, 2016
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A sintered cemented carbide body including tungsten carbide, and a substantially cobalt-free binder including an iron-based alloy sintered with the tungsten carbide. The iron-based alloy is approximately 2-25% of the overall weight percentage of the sintered tungsten carbide and iron-based alloy. The tungsten carbide may be approximately 90 wt % and the iron-based alloy may be approximately 10 wt % of the overall weight percentage of the sintered tungsten carbide and iron-based alloy. The tungsten carbide may comprise a substantially same size before and after undergoing sintering. The iron-based alloy may be sintered with the tungsten carbide using a uniaxial hot pressing process, a spark plasma sintering process, or a pressureless sintering process. The sintered tungsten carbide and iron-based alloy has a hardness value of at least 15 GPa and a fracture toughness value of at least 11 MPa√m.

First claim

What is claimed is:

1. A method of forming a tungsten carbide cemented body, the method comprising:
providing tungsten carbide; and
sintering a substantially cobalt-free binder comprising a dispersion strengthened, iron-based alloy that comprises iron, nickel and zirconium, wherein said cobalt-free binder is sintered with, and uniformly distributed around, the tungsten carbide,
wherein the sintered tungsten carbide and iron-based alloy comprises a hardness value of at least 15 GPa and a fracture toughness value of at least 11 MPa√m
and further wherein the iron-based alloy comprises a solid solution phase without a graphite.

2. The method of claim 1 , wherein the sintering comprises a uniaxial hot pressing process.

3. The method of claim 1 , wherein the sintering comprises a field assisted sintering technology process.

4. The method of claim 1 , wherein the sintering comprises a pressureless sintering process.

5. The method of claim 1 , wherein the iron-based alloy is approximately 2-25% of the overall weight percentage of the sintered tungsten carbide and iron-based alloy.

6. The method of claim 1 , wherein the tungsten carbide comprises approximately 90 wt % and the iron-based alloy comprises approximately 10 wt % of the overall weight percentage of the sintered tungsten carbide and iron-based alloy.

7. The method of claim 1 , wherein the tungsten carbide comprises a substantially same size before and after undergoing sintering.

8. The method of claim 1 , wherein the tungsten carbide comprises an average microparticle size of approximately 0.5-20 μm.

9. The method of claim 1 , wherein the substantially cobalt-free binder comprises a particle diameter of less than 100 nm.

10. The method of claim 1 , wherein the iron-based alloy binder comprises zirconium.

Assignees

• U S Army Res Laboratory Attn Rdrl Loc I
• Us Army

Inventors

• Pittari Iii John J
• Kilczewski Steven M
• Swab Jeffrey J
• Darling Kristopher A
• Hornbuckle Billy C
• Murdoch Heather A
• Dowding Robert J

Classifications

• C22C1/051

  Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor · CPC title

• C22C29/02 Primary

  based on carbides or carbonitrides · CPC title

• B22F3/105 Primary

  by using electric current {other than for infrared radiant energy}, laser radiation or plasma (B22F3/11 takes precedence){; by ultrasonic bonding (B22F3/115 takes precedence)} · CPC title

• B22F3/14

  simultaneously · CPC title

• C22C29/067

  comprising a particular metallic binder · CPC title