Hardmetals and method for producing the same

Patent metadata

Field	Value
Publication number	US-12006559-B2
Application number	US-202017767496-A
Country	US
Kind code	B2
Filing date	Oct 5, 2020
Priority date	Oct 11, 2019
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

The invention concerns the field of hardmetal materials and relates to hardmetals such as those which can, for example, be used as cutting material for tools. The object of the present invention is to specify hardmetals which include a novel concept for the structural composition of the hardmetals. The object is attained with hardmetals which are at least made up of hard phases in particle form and metal binder arranged therebetween, wherein a high-entropy hard phase (HEH) is composed of at least four metals (Me) of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides of the metals, wherein the respective amounts of the metals in the HEH are essentially equal.

First claim

The invention claimed is:

1. Hardmetals at least made up of hard phases in particle form and metal binder arranged therebetween, wherein a high-entropy hard phase (HEH), the content of which in the hardmetal according to the invention is at least 50 vol %, is composed of at least four metals (Me) of the 4th and/or 5th and/or 6th subgroup of the periodic table of elements (PTE) in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides of the metals, and wherein the respective amount x, y, and z in total of the carbon (C), nitrogen (N), and oxygen (O) in the carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides of the metals of the 4th and/or 5th and/or 6th subgroup of the PTE is in accordance with MeC x N y O z satisfies 0.7≤x+y+z≤1, and wherein the respective amounts of the metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the at least four metals in the HEH are essentially equal or the amount of one or more of said metals differs therefrom by maximally 20 at. %, and wherein the carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides of the metals of the 4th and/or 5th and/or 6th subgroup of the PTE are present in each hard phase particle as a solid solution, and furthermore maximally 50 vol % of the hard phases have a different hard phase composition, and wherein all metal binders are present in the amounts of 0.1 to 40 vol %.

2. The hardmetals according to claim 1 , in which 50-100 vol % of the hard phases are an HEH of at least four metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides.

3. The hardmetals according to claim 1 , in which 0-50 vol % of the hard phases in the hardmetal are composed of one, two, or three metals of the 4th and/or 5th and/or 6th subgroup of the periodic table of elements (PTE) in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides of the metals.

4. The hardmetals according to claim 1 , in which the hard phases are composed of carbides or nitrides of the metals of the 4th and/or 5th and/or 6th subgroup of the PTE.

5. The hardmetals according to claim 1 , in which the respective amounts of x, y, and z in total of the carbon (C), nitrogen (N), and oxygen (O) in the carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides with metals of the 4th and/or 5th and/or 6th subgroup of the PTE is in accordance with MeC x N y O z satisfies 0.9≤x+y+z≤1.

6. The hardmetals according to claim 1 , in which the amounts of the metals are present according to the following:
HEH has a number of n metals of the 4th and/or 5th and/or 6th subgroup of the PTE with n=4 to 9,

wherein
in the case of n=4 to 6 the amounts of the respective metals can differ according to (1/n 100)±1.0 at. %, and/or
in the case of n=7 to 9 the amounts of the respective metals can differ according to (1/n 100)±5 at. %, and/or
the amounts of n−3 (n minus 3) of the metals can also differ by respective amounts of >10 at. %, in relation to the total metal content in the HEH, wherein the amount of one of the metals can maximally be 70 at. % in relation to the total metal content of the HEH.

7. The hardmetals according to claim 1 , in which each amount of a metal differs by maximally 20 at. %.

8. The hardmetals according to claim 1 , in which the hard phase HEH is present such that it is composed of five or more metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides.

9. The hardmetals according to claim 1 , in which, in the HEH of at least four metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, and/or oxycarbonitrides, the amount of each of the at least four metals is essentially equal.

10. The hardmetals according to claim 1 , in which metals of hard phases are selected from a group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W.

11. The hardmetals according to claim 1 , in which the metal binders are any of Co, Ni, Fe, Mn, Cu, Cr, Ti, or mixtures thereof.

12. The hardmetals according to claim 1 , in which 5 to 32 vol % metal binder is contained in the hardmetals.

13. The hardmetals according to claim 1 , wherein:
the metal binders are Co, Ni, Fe, Mn, Cu, Cr, Ti, or mixtures thereof in the form of low-carbon or high-carbon steels or high-entropy metal alloys.

14. The hardmetals according to claim 1 , in which 80-98 vol % of the hard phases are an HEH of at least four metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, oxy carbides, and/or oxycarbonitrides.

15. The hardmetals according to claim 1 , in which the hard phase HEH is present such that it is composed of six or more metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, oxycarbides, and/or oxycarbonitrides.

16. A method for producing hardmetals comprising:
mixing and synthesizing powders from at least four metals of the 4th and/or 5th and/or 6th subgroup of the periodic table of elements (PTE) in the form of carbides, nitrides, carbonitrides, and/or oxycarbonitrides into an HEH powder or into HEH granules;
adding maximally 50 vol % additional hard phase powders or hard phase granules to the HEH powder or the granules of the HEH;
mixing the hard phase powders or hard phase granules with metal binder in powder form in an amount of 0.1 to 40 vol %; and
sintering hardmetal powder or hardmetal granules, and after shaping the hardmetal powder or hardmetal granules to form shaped component parts, and after forming shaped component parts, sintering the shaped component parts.

17. The method according to claim 16 , wherein: in the shaping, the component parts are shaped from the mixture with organic binders, the organic binders are then removed, and then the shaped component parts are sintered.

18. The method according to claim 16 , wherein:
the shaping is performed by pressing, extruding, injection molding, CIP (cold isostatic pressing), and/or by additive shaping.

19. The method according to claim 16 , wherein:
the sintering occurs in a pressure-free or pressure-assisted manner by means of sinter hot isostatic pressing, hot isostatic pressing (HIP), hot pressing, or SPS.

20. The method according to claim 16 , wherein:
at least five or six or seven powders of metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of carbides, nitrides, carbonitrides, and/or oxycarbonitrides are mixed and the mixture is synthesized with metal binders in situ during the sintering to form hardmetals containing HEH.

21. The method according to claim 16 , wherein:
four powders of metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of carbides and/or nitrides are mixed and the mixture is synthesized with metal binders in situ during the sintering to form hardmetals containing HEH.

22. The method according to claim 16 , wherein:
0 to <50 vol % of powders from hard phases of one or two or three metals of the 4th and/or 5th and/or 6th subgroup of the PTE in the form of a solid solution of carbides, nitrides, carbonitrides, and/or oxycarbonitrides are used.

23. The method according to clai

Assignees

• Fraunhofer Ges Forschung

Inventors

• Pötschke Johannes
• Herrmann Mathias

Classifications

• C22C29/02

  based on carbides or carbonitrides · CPC title

• C22C29/04

  based on carbonitrides · CPC title

• C22C29/12

  based on oxides · CPC title

• C22C29/16

  based on nitrides {(containing cubic BN or wurtzitic BN and diamond C22C26/00)} · CPC title

• B22F1/10

  Metallic powder containing lubricating or binding agents; Metallic powder containing organic material · CPC title