Method for producing an energy-storing container made of lightweight steel

Patent metadata

Field	Value
Publication number	US-10253399-B2
Application number	US-201615003503-A
Country	US
Kind code	B2
Filing date	Jan 21, 2016
Priority date	Nov 26, 2010
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

An energy-storing container is made of a lightweight steel having the following chemical composition (in wt %): C 0.04-2%; Mn 14-30%; Al 1.5-12%; Si 0.3-3%; Cr 0.12-6%, and additionally one or more of the following elements: Ti, V, Nb, B, Zr, Mo, Ni, Cu, W, Co, P, N, each at up to 5% and in total at up to 10%, wherein the remainder is Fe including common steel tramp elements, wherein the concrete alloy composition is selected in order to limit the α′-martensite fraction before or after a forming process to no more than 3%, with the stipulation that the α′-martensite equivalent according to 0.1*wt % Mn+wt % C+0.05*wt % Si is between 3.4 and 10.5.

First claim

What is claimed is:

1. A method of minimizing hydrogen embrittlement of a lightweight steel with the following chemical composition (in wt %):
C 0.04-2%
Mn 14-30%
Al 1.5-12%
Si 0.3-3%
Cr 0.12-6%,
one or more elements selected from Ti, V, Nb, B, Zr, Mo, Ni, Cu, W, Co, P, and N, each up to 5% and in total up to 10%, wherein the remainder is Fe including common steel tramp elements, said method comprising:
limiting a proportion of α′-martensite allowed in a lightweight steel to a maximum of 3% by calculating an α′-martensite equivalent according to the formula:
0.1*wt % Mn+weight % C+0.5*wt % Al+0.05*wt % Si≥3.6≤10.5;

and
determining a Mn, Al, C and Si content in accordance with the calculated α′-martensite equivalent for formulation of the lightweight steel.

2. The method of claim 1 , wherein the Cr content is in the range from 2 to 6%.

3. The method of claim 1 , wherein the Cr content is in the range from 0.12 to <2%.

4. The method of claim 1 , wherein the lightweight construction steel has a triplex structure with finely distributed kappa carbides and the following chemical composition (in wt %):
C 0.5-1.2%
Mn 14-22%
Al 6-10%
Si 0.3-3%
Cr <4%.

5. The method of claim 1 , further comprising producing the energy storing container form the steel with the Mn, Al, C and Si content according to the calculated α′-martensite equivalent.

6. The method of claim 1 , wherein the lightweight steel has an elongation at break A80 of >40% for producing complex structured containers by forming.

Assignees

• Salzgitter Flachstahl Gmbh

Inventors

• Braun Michael
• Otto Manuel
• Georgeou Zacharias
• Springub Bianca

Classifications

• C22C38/56

  with more than 1.7% by weight of carbon · CPC title

• C22C38/42

  with copper · CPC title

• C22C38/001

  containing N · CPC title

• C22C38/54

  with boron · CPC title

• C22C38/52

  with cobalt · CPC title