Loading patent…
AssigneeNippon Steel & Sumitomo Metal Corporation
InventorsYoshifumi Kobayashi, Kazuyuki Kawano, Yasunori Itoh, Shinichi Suzuki, Shintaro Yamanaka
Estimating the term…
On part of a surface of a metal sheet that is to be heated by radiant heat transfer with a near-infrared ray, a region where reflectance for a radiant ray is made lower than that of the original surface of the metal sheet is formed. As reflectance reducing treatment, painting or thermal spraying in a blackish color, plating in a blackish color, treatment for increasing roughness of the surface of the metal sheet, blasting, etching, blackening, surface layer quality changing treatment of the metal sheet, or the like can be adopted. The metal sheet is turned into a heated metal sheet partially having a different temperature by being heated by radiant heat transfer, and thereafter, the heated metal sheet is subjected to thermal processing accompanied by cooling, for example, by hot stamping.
A metal sheet comprising a reflectance-reduced region where reflectance for a radiant ray is reduced formed only on a part of a surface of the metal sheet that is to be heated by radiant heat transfer, and wherein the reflectance-reduced region comprises Al2O3—TiO2-based thermal spray material.
Dependencies are inferred from the claim text.