Machinability improving composition

Patent metadata

Field	Value
Publication number	US-9393617-B2
Application number	US-201414451073-A
Country	US
Kind code	B2
Filing date	Aug 4, 2014
Priority date	Dec 22, 2008
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

An iron-based powder composition is provided comprising, in addition to an iron-based powder, a minor amount of a machinability improving additive comprising at least one silicate from the group of phyllosilicates. The technology further concerns the use of the machinability improving additive and a method for producing an iron-based sintered part having improved machinability.

First claim

The invention claimed is:

1. An iron-based powder composition comprising:
an iron-based powder; and
a machinability improving additive in powder form, said machinability improving additive comprising a bentonite in powder form, wherein the content of the machinability improving additive is 0.05-1% by weight of the iron-based powder composition, wherein the average particle size, X 50 , of the machinability improving additive is below 20 μm.

2. The iron-based powder composition according to claim 1 , wherein the average particle size, X 50 , of the machinability improving additive is below 10 μm.

3. The iron-based powder composition according to claim 1 , wherein the average particle size, X 50 , of the machinability improving additive is below 5 μm.

4. The iron-based powder composition according to claim 1 , wherein the particle size, Xgg, of the machinability improving additive is below 50 μm.

5. The iron-based powder composition according to claim 1 , wherein the particle size, X 99 , of the machinability improving additive is below 30 μm.

6. The iron-based powder composition according to claim 1 , wherein the iron-based powder comprises less than 10% by weight of alloying elements.

7. The iron-based powder composition according to claim 1 , wherein the content of the machinability improving additive is 0.05-0.3% by weight of the iron-based powder composition.

8. The iron-based powder composition according to claim 1 , wherein the content of the machinability improving additive is 0.05-0.2% by weight of the iron-based powder composition.

9. A method for producing an iron-based sintered part having improved machinability, comprising:
preparing the iron-based powder composition of claim 1 ;
compacting the iron-based powder composition at a compaction pressure of 400-1200 MPa;
sintering the compacted part at a temperature of 1000-1300° C.; and
optionally, heat treating the sintered part.

10. A method for preparing an iron-based powder composition, the method comprising:
providing an iron-based powder; and
admixing the iron-based powder with a machinability improving additive in powder form to form the iron-based powder composition, the machinability improving additive comprising bentonite, wherein the bentonite is 0.05-1% by weight of the iron-based powder composition, wherein the average particle size, X 50 , of the machinability improving additive is below 20 μm.

11. The method according to claim 10 , wherein the average particle size, X 50 , of the machinability improving additive is below 10 μm.

12. The method according to claim 10 , wherein the average particle size, X 50 , of the machinability improving additive is below 5 μm.

13. The method according to claim 10 , wherein the particle size, X 99 , of the machinability improving additive is below 50 μm.

14. The method according to claim 10 , wherein the particle size, X 99 , of the machinability improving additive is below 30 μm.

15. The method according to claim 10 , wherein the iron-based powder comprises less than 10% by weight of alloying elements.

16. The method according to claim 10 , wherein the content of the machinability improving additive is 0.05-0.3% by weight of the iron-based powder composition.

17. The method according to claim 10 , wherein the content of the machinability improving additive is 0.05-0.2% by weight of the iron-based powder composition.

18. A method for preparing an iron-based powder composition, the method comprising:
providing an iron-based powder; and
admixing the iron-based powder with a machinability improving additive in powder form to form the iron-based powder composition, the machinability improving additive comprising bentonite, wherein the bentonite is 0.05-1% by weight of the iron-based powder composition, wherein the iron-based powder comprises less than 10% by weight of alloying elements.

19. The method according to claim 18 , wherein the content of the machinability improving additive is 0.05-0.3% by weight of the iron-based powder composition.

20. The method according to claim 18 , wherein the content of the machinability improving additive is 0.05-0.2% by weight of the iron-based powder composition.

Assignees

• Hoeganaes Ab Publ
• Hoganas Ab Publ

Inventors

• Andersson Olof
• Hu Bo

Classifications

• B22F1/12

  Metallic powder containing non-metallic particles (containing lubricating or binding agents or organic material B22F1/10) · CPC title

• B22F1/105

  containing inorganic lubricating or binding agents, e.g. metal salts · CPC title

• C22C33/0264

  the maximum content of each alloying element not exceeding 5% · CPC title

• B22F3/12

  Both compacting and sintering (by forging B22F3/17) · CPC title

• C22C33/02

  by powder metallurgy · CPC title