The use of X-ray diffraction for phase identification of press hardened steels

• Autor(a) principal: COUTO, C.P.
• Data de Publicação: 2017
• Outros Autores: COSTA, P.D.O.L., MARTINEZ, L.G., TURRILLAS, X., ROSSI, J.L., WORKSHOP OF APPLIED CRYSTALLOGRAPHY TO MATERIALS SCIENCE AND ENGINEERING, 6th
• Tipo de documento: Artigo de conferência
• Título da fonte: Repositório Institucional do IPEN
• Texto Completo: http://repositorio.ipen.br/handle/123456789/27579

The numbers of hot stamped components have been steadily increasing in the automotive industry. Press hardened steels are generally used in hot stamping process since at the end of the process, the steel may achieve a tensile strength about 1500 MPa. The hot stamping process consists to heat the steel blank at total austenitization temperature and to transfer the blank into the press tooling for shaping and fast cooling to fully martensitic transformation. The transfer of the blank from the furnace to the press might promote at some extent, steel oxidation. The application of metallic coatings avoids this hindrance. The Al-Si has been the most applied coating on steel. In parallel, alternative coatings such as Zn-Ni have been developed. It is known that the heating causes chemical elements diffusion, which results in intermetallic formation between the elements presents in the coating and in the substrate. This study had the objective of characterizing hot stamped and coated 25MnB5 steel samples with Al-Si and Zn-Ni, with X rays diffraction (XRD) technique. Some literature suggested phases such as Zn-Fe, Zn-Ni-Fe or Al-Fe-Si were not seen on XRD results. Nonetheless, X-ray diffraction detected the presence of ZnO and ??-Fe for Zn-Ni coated steel plate and Al5Fe2, AlFe3 and ??-Fe for the Al-Si coated steel plate.