Effect of the tempering cooling rate on the toughness of bainite welds
CAI Zhipeng1, WANG Liang1, PAN Jiluan1, QIAO Shangfei2, HUO Xin2, WANG Peng2, LIU Xia1,2
1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China;
2. Process Department of Turbine Works, Shanghai Electric Power Generation Equipment Co., Ltd., Shanghai 200240, China
Abstract：Large components with thick walls have slow cooling rates during tempering. Improper tempering parameters can cause temper brittlement in CrMoV steels. The effect of tempering cooling rate on the toughness of bainite welds is investigated for thick circular components. Slow tempering cooling rates reduce the weld toughness. Multi-layer, multi-pass welds experience layered brittle fracture, which illustrates that slow tempering cooling rates affect only local welds with the greatest toughness reduction in the heat affected zone (HAZ) between the layers. Auger electron spectroscopy (AES) analyses show that the segregation of C, O and Ni along the prior austenite grain boundaries is associated with the toughness reduction.
蔡志鹏, 王梁, 潘际銮, 乔尚飞, 霍鑫, 王朋, 刘霞. 回火冷却速度对贝氏体焊缝韧性的影响[J]. 清华大学学报（自然科学版）, 2015, 55(10): 1045-1050.
CAI Zhipeng, WANG Liang, PAN Jiluan, QIAO Shangfei, HUO Xin, WANG Peng, LIU Xia. Effect of the tempering cooling rate on the toughness of bainite welds. Journal of Tsinghua University(Science and Technology), 2015, 55(10): 1045-1050.
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2015, Vol. 55 
