Bending properties of 1 800 MPa grade microalloyed hot stamping steel
ZHAO Hai-feng1,2, XU De-chao1,2, ZHANG Bo-ming1,2, TENG Hua-xiang1,2
1. Research Institute of Technology,Shougang Group Co., Ltd., Beijing 100043, China; 2. Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology, Beijing 100043, China
Abstract：Through three-point bending test and microscopic analysis of mechanical properties, the effect of different austenitizing temperatures on the bending properties of 1 800 MPa grade microalloyed hot stamping steel was studied. The results showed that when the austenitizing temperature was between 830-890 ℃, the bending angle of test steel was bigger than 55°. When the austenitizing temperature reached 920 ℃, the energy absorption capacity and the maximum bearing capacity of test steel were significantly reduced. Due to the interaction between the increase of tensile strength caused by the increase of KAM and the weakening of tensile strength caused by the increase of austenite grain size and the coarsening of lath martensite, the mechanical properties of test steel did not change significantly under different austenitizing temperatures and test directions.
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2021, Vol. 31 
