Hot local compression and die quench ausforming of quenchable steel sheet

Abstract. Characteristics of hot local compression were investigated to apply hot stamping to a plate forging process. A heated quenchable steel sheet was locally compressed in a thickness direction and held with a punch at the bottom dead centre for die quenching. The effect of a forming temperature on reduction ratio and hardness was examined. Holding at the bottom dead centre improved the compression ratio due to plastic deformation during martensite transformation. Additionally, the quenched hardness of the locally compressed portion increased due to ausformig.