Recently, fuel efficiency regulations due to environmental problems have been strengthened, and demand for eco-friendly cars has increased. As a result, the automobile business has increased the application of hot stamping parts in high lightweight, h...
Recently, fuel efficiency regulations due to environmental problems have been strengthened, and demand for eco-friendly cars has increased. As a result, the automobile business has increased the application of hot stamping parts in high lightweight, high-strength collision safety parts compared to conventional internal combustion locomotives to satisfy various fuel efficiency regulations and environmental regulations.
In the case of an Al-Si plated boron steel plate used for general hot stamping, the Al-Si coating layer has the advantage of preventing the formation of an oxide layer when the material is heated, but the Al-Si coating layer melts together during welding to produce Fe3(Al, Si) intermetallic compounds. Furthermore, when hot stamping is carried out using an Al-Si plated boron steel plate, the production unit price of the parts is raised by paying the license cost by the process patent.
This paper proposes a hot stamping process technology to improve the surface properties of uncoated boron steel sheets. Hat Type specimens were subjected to hot stamping using an uncoated boron steel sheet and an Al-Si coated boron steel sheet, and the changes in surface properties before and after heat treatment were comparatively analyzed. In addition, using the Gleeble 3500 instrument capable of atmospheric control, we explored a method for improving surface characteristics according to atmospheric control conditions. An induction heating hot stamping simulator was then constructed and controlled atmosphere conditions were used to simulate the process to perform hot stamping of hat parts. After that, the oxidized layer and the decarburized layer were quantitatively analyzed for each part position.