Binder for powder metallurgy, mixed powder for powder metallurgy, and sintered body

Patent metadata

Field	Value
Publication number	US-10240032-B2
Application number	US-201414762725-A
Country	US
Kind code	B2
Filing date	Feb 17, 2014
Priority date	Mar 4, 2013
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

The present invention provides a binder which has excellent effect on suppression of segregation or dust emission, while exhibiting excellent fluidity both at ordinary temperatures and at high temperatures. The present invention is a binder which is blended for use in a mixed powder for powder metallurgy, said mixed powder containing an iron-based powder and an auxiliary starting material powder. This binder is characterized by being composed of one or more polymers that are selected from among butene polymers having a melting point of from 50° C. to 85° C. (inclusive) and a heated melt fluidity at 190° C. of from 2.0 g/10 minutes to 3.6 g/10 minutes (inclusive) and methacrylic acid polymers having a weight average molecular weight of 1,000,000 or less.

First claim

The invention claimed is:

1. A binder, comprising:
a butene polymer having a melting point of 50 to 85° C. and a melt fluidity at 190° C. of 2.0 to 3.6 g/10 min, and
optionally a methacrylic acid polymer having a weight-average molecular weight of 1,000,000 or less.

2. The binder of claim 1 , comprising the methacrylic acid polymer.

3. The binder of claim 2 , comprising the methacrylic acid polymer in an amount of at least 5 mass %.

4. The binder of claim 1 , wherein the butene polymer is a copolymer of butene and a lower alkylene.

5. The binder of claim 4 , wherein the butene polymer is a butene-propylene copolymer or a butene-ethylene copolymer.

6. A mixed powder, comprising:
an iron-based powder;
an auxiliary material powder; and
the binder of claim 1 .

7. The mixed powder of claim 6 , wherein a content of the binder is 0.01 to 0.5 mass % relative to a total of 100 mass % of the iron-based powder and the auxiliary material powder.

8. The mixed powder of claim 6 , wherein at least some of the iron-based powder and at least some of the auxiliary material powder are covered with the binder.

9. A sintered body, produced by a method comprising:
pressing and sintering the mixed powder of claim 6 .

Assignees

• Kobe Steel Ltd

Inventors

• Ito Yoshihiro
• Yoshikawa Eiichiro
• Akagi Nobuaki
• Sato Mitsuhiro

Classifications

• B22F1/10

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

• B22F1/00

  Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties · CPC title

• C22C38/00 Primary

  Ferrous alloys, e.g. steel alloys (cast-iron alloys C22C37/00) · CPC title

• C08L33/02 Primary

  Homopolymers or copolymers of acids; Metal or ammonium salts thereof · CPC title

• B22F3/12

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