Welding high strength steels
The steel industry addressed the demands for weight reduction and strength by developing the new multiphase steels (HCT600). But the high strengths of the steels cause other problems in production. The pressing forces reach their limits and the springback behaviour is another problem. Hot-formed steels have been developed as a good alternative, e.g. 22Mnb5, which have good formability and only reach their high strength after heat treatment. Special control algorithms (IQ Flex) for spot welding were developed for this purpose.