Cemented carbide articles and applications thereof

Patent metadata

Field	Value
Publication number	US-2017306456-A1
Application number	US-201715645475-A
Country	US
Kind code	A1
Filing date	Jul 10, 2017
Priority date	Dec 17, 2014
Publication date	Oct 26, 2017
Grant date	—

Abstract

In one aspect sintered cemented carbide articles are described herein which, in some embodiments, exhibit enhanced resistance to wear and thermal fatigue. Further, sintered cemented carbide articles described herein can tolerate variations in carbon content without formation of undesirable phases, including eta phase and/or free graphite (C-type porosity). Such tolerance can facilitate manufacturing and use of carbide grades where carbon content is not strictly controlled. A sintered cemented carbide body described herein comprises a hard particle phase including tungsten carbide and a metallic binder phase comprising at least one of cobalt, nickel and iron and one or more alloying additives, wherein the sintered cemented carbide has a magnetic saturation (MS) ranging from 0% to 73% and no eta phase.

First claim

1 . A method of producing a sintered cemented carbide article comprising:
providing a carbon deficient grade powder comprising a tungsten carbide phase and a metallic binder phase comprising at least one of cobalt, nickel and iron; providing an alloying additive to the metallic binder phase of the grade powder; consolidating the grade powder into a green part; and sintering the green part to provide the sintered cemented carbide article having a MS of 0% to 74% and no eta phase.

2 . The method of claim 1 , wherein the carbon deficient grade powder has carbon content of 82% to 99.5% of stoichiometric carbon content, for the grade powder.

3 . The method of claim 1 , wherein the carbon deficient grade powder has carbon content of 82% to 99% of stoichiometric carbon content for the grade powder:

4 . The method of claim 1 , wherein the carbon deficient grade powder has carbon content of 94% to 98% of stoichiometric carbon content for the grade powder.

5 . The method of claim 1 , wherein the alloying additive comprises one or more metallic elements.

6 . The method of claim 5 , wherein the metallic elements are transition metals.

7 . The method of claim 6 , wherein the transition metals are selected from Groups IIIB- VIIIB of the Periodic Table.

8 . The method of claim 6 , wherein the transition metals are selected from the group consisting of tungsten, ruthenium, manganese, copper, rhenium, chromium, osmium and molybdenum.

9 . The method of claim 6 , wherein the alloying additive has a hexagonal close-packed crystalline structure.

10 . The method of claim 6 , wherein the alloying additive has a cubic crystalline structure.

11 . The method of claim 1 , wherein the MS of the sintered cemented carbide article is 3-73%.

12 . The method of claim 1 , wherein the MS of the sintered cemented carbide article is 5-70%.

13 . The method of claim 1 , wherein the MS of the sintered cemented carbide article is 40-65%.

14 . The method of claim 1 , wherein the alloying additive is present in an amount of up to 50 wt. % of the metallic binder phase.

15 . The method of claim 1 , wherein the alloying additive is present in an amount of 10-30 wt. % of the metallic binder phase.

16 . The method of claim 1 , wherein the alloying additive is present in an amount of 30-50 wt. % of the metallic binder phase.

17 . The method of claim 1 , wherein carbon deficient grade powder further comprises at least one or tantalum carbide, niobium carbide, vanadium carbide, chromium carbide, zirconium carbide, hafnium carbide, titanium carbide and solid solutions thereof.

18 . The method claim 1 , wherein the sintered cemented carbide article has hardness of at least 80 HRA.

19 . The method of claim 1 , wherein the tungsten carbide phase has an average grain size of 0.5 um to 3 μm.

20 . The method of claim 1 , wherein carbon is not added to the grade powder composition.

Assignees

• Kennametal Inc

Inventors

• Trivedi Pankaj B
• Mehrotra Pankaj Kumar

Classifications

• C22C29/08 Primary

  based on tungsten carbide · CPC title

• B22F2005/001

  Cutting tools, earth boring or grinding tool other than table ware · CPC title

• C22C29/005

  comprising a particular metallic binder · CPC title

• C22C29/04

  based on carbonitrides · CPC title

• C22C29/067

  comprising a particular metallic binder · CPC title