Copper alloy plate, plating film-attached copper alloy plate, and methods respectively for manufacturing these products

Patent metadata

Field	Value
Publication number	US-11781234-B2
Application number	US-201917416551-A
Country	US
Kind code	B2
Filing date	Dec 18, 2019
Priority date	Dec 26, 2018
Publication date	Oct 10, 2023
Grant date	Oct 10, 2023

Abstract

A copper alloy plate including 0.3 mass % or more and 1.2 mass % or less of Mg, 0.001 mass % or more and 0.2 mass % or less of P, and the balance Cu with inevitable impurities in a thickness center portion in a plate thickness direction; Mg concentration on a plate surface is 30% or less of bulk Mg concentration at the thickness center portion; a surface layer part having a depth from the plate surface to where it is 90% of the bulk Mg concentration is provided; and in the surface layer part, the Mg concentration increases from the plate surface toward the thickness center portion with a concentration gradient 1.8 mass %/μm or more and 50 mass %/μm or less.

First claim

The invention claimed is:

1. A copper alloy plate containing 0.3 mass % or more and 1.2 mass % or less of Mg, 0.001 mass % or more and 0.2 mass % or less of P, and the balance Cu with inevitable impurities in a thickness center portion in a plate thickness direction, wherein
surface Mg concentration on a plate surface is 30% or less of bulk Mg concentration at the thickness center portion; and
in a surface layer part from the plate surface to a depth in which Mg concentration is 90% of the bulk Mg concentration, the Mg concentration increases from the plate surface toward the thickness center portion with a concentration gradient 1.8 mass %/μm or more and 50 mass %/μm or less.

2. The copper alloy plate according to claim 1 , wherein a thickness of the surface layer part is 0.6 μm or less.

3. A plating film-attached copper alloy plate further comprising a plating film formed on the surface layer part of the copper alloy plate of the copper alloy plate according to claim 1 .

4. The plating film-attached copper alloy plate according to claim 3 , wherein average concentration of Mg in the plating film is 10% or less of the bulk Mg concentration.

5. The plating film-attached copper alloy plate according to claim 3 , wherein the plating film consists of one or more layers selected from tin, copper, zinc, nickel, gold, silver, palladium, and alloy thereof.

6. A method of manufacturing the copper alloy plate according to claim 1 , comprising an Mg condense treatment forming the concentration gradient of Mg in a plate thickness direction and forming an Mg condense part in which Mg is condensed by diffusing Mg in an Mg containing copper alloy plate toward a surface of the Mg containing copper alloy plate and a surface part remove treatment forming the surface layer part by removing the Mg condense part.

7. A method of manufacturing the plating film-attached copper alloy plate according to claim 3 , wherein the plating film is formed by electrolytic plating treatment with current density 0.1 A/dm 2 or more and 60 A/dm 2 .

8. The method of manufacturing the plating film-attached copper alloy plate according to claim 7 , wherein after the electrolytic plating treatment forming the plating film including tin, reflow treatment is performed with heating peak temperature 230° C. or more and 330° C. or less and heating time at the heating peak temperature is 0.5 seconds or more and 30 seconds or less.

Assignees

• Mitsubishi Materials Corp

Inventors

• Miyashima Naoki
• Maki Kazunari
• Funaki Shinichi
• Kubota Kenji

Classifications

• C25D5/10 Primary

  Electroplating with more than one layer of the same or of different metals (for bearings C25D7/10) · CPC title

• C22C9/00

  Alloys based on copper · CPC title

• C25D5/505

  of electroplated tin coatings, e.g. by melting · CPC title

• Y10T428/12903

  Cu-base component · CPC title

• B23K35/26

  with the principal constituent melting at less than 400°C · CPC title