Austenitic High Mn Stainless Steel for High Pressure Hydrogen Gas

• US 20090159602A1
• Filed: 10/27/2006
• Published: 06/25/2009
• Est. Priority Date: 11/01/2005
• Status: Abandoned Application

• Current Assignee: Nippon Steel & Sumikin Stainless Steel Corporation (Nippon Steel Corporation)
• Original Assignee: Nippon Steel & Sumikin Stainless Steel Corporation (Nippon Steel Corporation)
• Inventors: Hatano, Masaharu, Takahashi, Akihiko
• Application Number:
  US12/084,305
• Publication Number:
  US 20090159602A1
• Time in Patent Office: Days
• US Class Current: 220/581
• CPC Class Codes: C22C 38/001 containing N
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/42 with copper
• CPC Class Codes: C22C 38/44 with molybdenum or tungsten
• CPC Class Codes: C22C 38/58 with more than 1.5% by weight of manganese

Abstract

The present invention proposes an austenitic high Mn stainless steel maintaining a hydrogen embrittlement resistance above that of SUS316L and adapted to a low temperature hydrogen environment by being designed in compositions to comprise, by mass %, C: 0.01 to 0.10%, N: 0.01 to 0.40%, Si: 0.1 to 1%, Cr: 10 to 20%, Mn: 6 to 20%, Cu: 2 to 5%, Ni: 1 to 6%, and a balance of Fe and unavoidable impurities and have an Md30 value of an indicator of an austenite stabilization degree satisfying −120<Md30<20, where Md30=497-462(C+N)-9.2Si-8.1Mn-13.7Cr-20(Ni+Cu)-18.5Mo

Claims

1. Austenitic high Mn stainless steel superior in hydrogen embrittlement resistance used in high pressure hydrogen gas environment, said austenitic high Mn stainless steel characterized by comprising, by mass %, C:

0.01 to 0.10%, N;

0.01 to 0.40%, Si;

0.1 to 1%, Cr;

10 to 20%, Mn;

6 to 20%, Cu;

2 to 5%, Ni;

1 to 6%, and a balance of Fe and unavoidable impurities and having an Md30 value of an indicator of an austenite stabilization degree satisfying the following formula (A);

−

120<

Md30<

20 

 

(A)

where, Md30(°

C.);

551-462(C+N)-9.2Si-8.1Mn-13.7Cr-29(Ni+Cu)-18.2Mo.

2. Austenitic high Mn stainless steel superior in hydrogen embrittlement resistance as set forth in claim 1 characterized by further containing, by mass %, Mo:

0.3 to 3.0%.

3. A high pressure hydrogen gas tank storing hydrogen gas of a pressure of 120 MPa or less, said high pressure hydrogen gas tank characterized in that the body and/or liner of said gas tank is comprised of austenitic high Mn stainless steel as set forth in claim 1.

4. A high pressure hydrogen gas pipe transporting hydrogen gas of a pressure of 120 MPa or less, said high pressure hydrogen gas pipe characterized in that said pipe is comprised of austenitic high Mn stainless steel as set forth in claim 1.