Mixed powder for powder metallurgy

Patent metadata

Field	Value
Publication number	US-12187976-B2
Application number	US-202017594561-A
Country	US
Kind code	B2
Filing date	Jan 28, 2020
Priority date	Apr 23, 2019
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

A mixed powder for powder metallurgy comprises: an iron-based powder; and a lubricant, wherein the lubricant consists of a low-melting-point lubricant having a melting point of 86° C. or less and a high-melting-point lubricant having a melting point of more than 86° C., the low-melting-point lubricant has at least one of an amide group, an ester group, an amino group, and a carboxyl group, a ratio R1 of the low-melting-point lubricant to whole of the lubricant is 5 mass % or more and less than 90 mass %, a ratio R2 of a mass of a free lubricant to a mass of a binding lubricant is 0 or more and 15 or less, and an amount R3 of the low-melting-point lubricant contained as the free lubricant is less than 0.10 parts by mass with respect to 100 parts by mass of the iron-based powder.

First claim

The invention claimed is:

1. A mixed powder for powder metallurgy, comprising:
an (a) iron-based powder; and
a (b) lubricant,
wherein the (b) lubricant contains a fatty acid metal soap,
the (b) lubricant consists of a low-melting-point lubricant having a melting point of 86° C. or less and a high-melting-point lubricant having a melting point of more than 86° C.,
the low-melting-point lubricant is at least one of a fatty acid monoamide having a melting point of 80° C. or more and a fatty acid having a melting point of 75° C. or more,
the low-melting-point lubricant has at least one selected from the group consisting of an amide group, an ester group, an amino group, and a carboxyl group,
a ratio R1 of the low-melting-point lubricant to whole of the (b) lubricant is 5 mass % or more and less than 90 mass %,
a ratio R2 of a mass of a (b2) free lubricant to a mass of a (b1) binding lubricant is 0 or more and 15 or less, where the (b1) binding lubricant is the (b) lubricant adhering to a surface of the (a) iron-based powder, and the (b2) free lubricant is the (b) lubricant not adhering to the surface of the (a) iron-based powder, and
an amount R3 of the low-melting-point lubricant contained as the (b2) free lubricant is less than 0.10 parts by mass with respect to 100 parts by mass of the iron-based powder.

2. The mixed powder for powder metallurgy according to claim 1 , wherein the (b1) binding lubricant and the (b2) free lubricant contain a fatty acid derivative having at least one of an alkyl group having a carbon number of 11 or more and an alkenyl group having a carbon number of 11 or more.

3. The mixed powder for powder metallurgy according to claim 1 , wherein a lubricant having a melting point of 100° C. or more is contained as the high-melting-point lubricant, and
a ratio R4 of the lubricant having a melting point of 100° C. or more to the whole of the (b) lubricant is 10 mass % or more.

4. The mixed powder for powder metallurgy according to claim 1 , wherein the high-melting-point lubricant is at least one selected from the group consisting of a fatty acid amide, a fatty acid metal soap, and a mixture thereof.

5. The mixed powder for powder metallurgy according to claim 1 , wherein the low-melting-point lubricant is a monoamide having a fatty chain containing an unsaturated bond.

6. The mixed powder for powder metallurgy according to claim 1 , further comprising one or both of an (e) alloying powder and a (f) machinability improver.

7. The mixed powder for powder metallurgy according to claim 6 , wherein one or both of the (e) alloying powder and the (f) machinability improver are adhered to the surface of the (a) iron-based powder via the (b1) binding lubricant.

8. A mixed powder for powder metallurgy, comprising:
an (a) iron-based powder;
a (b) lubricant; and
at least one of (c) carbon black and a (d) carbonate,
wherein the (b) lubricant does not contain a fatty acid metal soap,
the (b) lubricant consists of a low-melting-point lubricant having a melting point of 86° C. or less and a high-melting-point lubricant having a melting point of more than 86° C.,
the low-melting-point lubricant has at least one selected from the group consisting of an amide group, an ester group, an amino group, and a carboxyl group,
a ratio R1 of the low-melting-point lubricant to whole of the (b) lubricant is 5 mass % or more and less than 90 mass %,
a ratio R2 of a mass of a (b2) free lubricant to a mass of a (b1) binding lubricant is 0 or more and 15 or less, where the (b1) binding lubricant is the (b) lubricant adhering to a surface of the (a) iron-based powder, and the (b2) free lubricant is the (b) lubricant not adhering to the surface of the (a) iron-based powder, and
an amount R3 of the low-melting-point lubricant contained as the (b2) free lubricant is less than 0.10 parts by mass with respect to 100 parts by mass of the iron-based powder.

9. The mixed powder for powder metallurgy according to claim 8 , wherein the (b1) binding lubricant and the (b2) free lubricant contain a fatty acid derivative having at least one of an alkyl group having a carbon number of 11 or more and an alkenyl group having a carbon number of 11 or more.

10. The mixed powder for powder metallurgy according to claim 8 , wherein a lubricant having a melting point of 100° C. or more is contained as the high-melting-point lubricant, and
a ratio R4 of the lubricant having a melting point of 100° C. or more to the whole of the (b) lubricant is 10 mass % or more.

11. The mixed powder for powder metallurgy according to claim 8 , wherein the high-melting-point lubricant is a fatty acid amide.

12. The mixed powder for powder metallurgy according to claim 8 , wherein the low-melting-point lubricant is a monoamide having a fatty chain containing an unsaturated bond.

13. The mixed powder for powder metallurgy according to claim 8 , further comprising one or both of an (e) alloying powder and a (f) machinability improver.

14. The mixed powder for powder metallurgy according to claim 13 , wherein one or both of the (e) alloying powder and the (f) machinability improver are adhered to the surface of the (a) iron-based powder via the (b1) binding lubricant.

Assignees

• Jfe Steel Corp

Inventors

• SHIMAMOTO Hanako
• Matsuoka Ryosuke
• Ashizuka Kohsuke
• Unami Shigeru

Classifications

• C10M2215/285

  used as base material · CPC title

• C10M2215/265

  used as base material · CPC title

• C10M2207/2895

  used as base material · CPC title

• C10M2207/2835

  used as base material · CPC title

• C10M2207/2815

  used as base material · CPC title