Method for creating a hardened steel assembly

Patent metadata

Field	Value
Publication number	US-9309581-B2
Application number	US-201414262534-A
Country	US
Kind code	B2
Filing date	Apr 25, 2014
Priority date	May 2, 2013
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A method of creating a hardened steel assembly from at least two parts may include the consecutive steps of first joining the at least two parts in a cold formed state to form an assembly, and then hardening the joined assembly.

First claim

The invention claimed is:

1. A method of creating a hardened steel assembly from at least two parts made of steel, comprising the consecutive steps of first joining the at least two parts in a cold formed state to form a steel assembly, the joining comprising a welding process which includes one or more of spot welding, laser welding, or gas metal arc welding, and then hardening the steel assembly.

2. The method according to claim 1 , further comprising forming at least one of the parts by pressing before the hardening process.

3. The method according to claim 1 , wherein the hardened steel assembly is removed from the hardening process at a temperature between 80 and 100 degrees centigrade inclusive.

4. The method according to claim 1 , wherein said steel of the hardened steel assembly is boron steel.

5. The method according to claim 1 , wherein said hardened steel assembly fully or in part constitutes a vehicle sub assembly.

6. The method according to claim 5 , wherein said vehicle sub assembly is a vehicle safety cage.

7. A method of manufacturing a vehicle safety cage comprising a hardened steel assembly, the hardened steel assembly made by the steps of: joining, by one of spot welding, laser welding, or gas metal arc welding, at least two parts made of steel in a cold formed state to form a steel assembly; and then hardening the steel assembly, to form a joined steel assembly.

8. The method of claim 7 , wherein at least one of said parts is formed by pressing before the hardening.

9. The method of claim 7 , wherein the method further comprises removing the hardened joined steel assembly from the hardening process at a temperature between 80 and 100 degrees centigrade inclusive.

10. The method of claim 7 , wherein said steel of the hardened steel assembly is boron steel.

Assignees

• Volvo Car Corp

Inventors

• Johansson Richard

Classifications

• B23K26/24

  Seam welding · CPC title

• B23K2103/04

  Steel {or steel} alloys · CPC title

• C21D9/46

  for sheet metals · CPC title

• B23K9/025 Primary

  for rectilinear seams · CPC title

• B23K2101/006

  Vehicles · CPC title