Effect of bismuth element with low melting point on embrittlement behavior of steel
LIU Hai-tao1,2,3, WANG Jian1, YANG Zheng-yuan1, YIN Bao-shu1, ZHANG Jia-de1, ZHANG Gao-xiang1
1. School of Materials Science and Engineering, Henan University of Science and Technology,Luoyang 471023, Henan, China; 2. Henan Key Laboratory of Non-ferrous Materials Science and Processing Technology, Luoyang 471023, Henan, China; 3. Collaborative Innovation Center of Non-ferrous Metals Henan Province, Luoyang 471023, Henan, China
Abstract：In order to prove the "two-sidedness" effect of low melting point elements bismuth during the machining and the high temperature deformation processes in the steel,the influence of bismuth on the embrittlement behavior of steel in different temperature ranges was studied by the cutting experiment,high temperature thermoplastic experiment and microstructure analysis. The results showed that embrittlement of steel by bismuth in the cutting process can promote the formation of "C-shaped" brittle chips and make bismuth free-cutting steel having an excellent machinability. This embrittlement behavior was mainly associated with the liquid metal embrittlement of bismuth in steel,which significantly reduced the plastic of steel at bismuth liquidus temperature. The influence of bismuth on the embrittlement behavior of steel during high temperature deformation was mainly related to the segregation of bismuth film at the austenite grain boundary,which endangered the grain boundary strength of steel,and then significantly reduced the thermoplastic behavior of steel at the experimental temperature range of 1 000 ℃ and below.
刘海涛, 王键, 杨争媛, 尹宝舒, 张家得, 张高祥. 低熔点元素铋对钢脆化行为的影响[J]. 钢铁, 2020, 55(1): 81-85.
LIU Hai-tao, WANG Jian, YANG Zheng-yuan, YIN Bao-shu, ZHANG Jia-de, ZHANG Gao-xiang. Effect of bismuth element with low melting point on embrittlement behavior of steel. Iron and Steel, 2020, 55(1): 81-85.
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2020, Vol. 55 
