Effect of Microstructure on the Mechanical Properties of 980MPa Grade Steel

摘要

The demand of 980DP steel with high yield ratio is increasing to satisfy the needs of anti-crashing and rollforming. They require good bendability and stretch flangeability. In addition, some automaker requires good spot weldability of 980DP steel1). It is well-known that high yield ratio is related with the volume fraction of second phases, and bendability and stretch flangeability with the differences of strength between the ferrite and hard phases2). It is also well-known that spot weldability is related with the content of carbon. The aim of this work was to investigate the effect of microstructure on the mechanical properties of 980MPa grade steel.