Method for bonding stainless steel members and stainless steel

• US 10,449,629 B2
• Filed: 11/22/2016
• Issued: 10/22/2019
• Est. Priority Date: 09/27/2013
• Status: Active Grant

• Current Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Original Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Inventors: Katoh, Masahito, Shiratori, Tomomi
• Primary Examiner(s): Stoner, Kiley S
• Application Number:
  US15/359,216
• Publication Number:
  US 20170072503A1
• Time in Patent Office: 1,064 Days
• Field of Search: 228193-195, 2282331-2341, 2282351-2353, 22826241-26242
• CPC Class Codes: B23K 20/021 Isostatic pressure welding
• CPC Class Codes: B23K 20/023 Thermo-compression bonding
• CPC Class Codes: B23K 20/227 with ferrous layer
• CPC Class Codes: B23K 2103/05 Stainless steel
• CPC Class Codes: C21D 2211/001 Austenite
• CPC Class Codes: C21D 2211/008 Martensite
• CPC Class Codes: C21D 6/002 containing Cr C21D6/004 takes precedence
• CPC Class Codes: C22C 38/001 containing N
• CPC Class Codes: C22C 38/002 containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/04 containing manganese
• CPC Class Codes: C22C 38/44 with molybdenum or tungsten
• CPC Class Codes: C22C 38/54 with boron
• CPC Class Codes: C22C 38/58 with more than 1.5% by weight of manganese

Abstract

A method for bonding stainless steel members includes: contacting a first stainless steel member with a second stainless steel member that has a strain exceeding 50% reduction; and heating the first and second stainless steel members to a re-crystallization initiation temperature or higher, after the contacting.

Claims

1. A method for bonding stainless steel members comprising:

transforming a second austenitic stainless steel member substantially into martensite by performing rolling with respect to the second austenitic stainless steel member at a temperature that is equal to an Md point or lower, the Md point being a temperature at which martensite transformation is achieved by processing;

contacting a first austenitic stainless steel member with the second austenitic stainless steel member; and

diffusion bonding by heating the first and second austenitic stainless steel members to an As temperature or higher, after the contacting,

wherein in the heating, the first austenitic stainless steel member and the second austenitic stainless steel member are heated to a temperature that is equal to the As temperature or higher and is equal to a re-crystallization initiation temperature plus 100 degrees C. or lower.

2. The method for bonding stainless steel members as claimed in claim 1, wherein the first austenitic stainless steel member contains at least 30 volume % of martensite.

4. The method for bonding stainless steel members as claimed in claim 1, wherein the first austenitic stainless steel member and the second austenitic stainless steel member are in a solid-phase during contacting.

3. A method for bonding stainless steel members comprising:

transforming a second austenitic stainless steel member substantially into martensite by performing rolling with respect to the second austenitic stainless steel member at a temperature that is equal to an Md point or lower, the Md point being a temperature at which martensite transformation is achieved by processing;

contacting a first austenitic stainless steel member that contains at least 30 volume % of martensite with the second austenitic stainless steel member; and

diffusion bonding by heating the first and second austenitic stainless steel members to an As temperature or higher, after the contacting.