TWIP钢的拉伸应变硬化行为.pdf

42 11 Vol.42, No. 11 2 0 0 7 11 Iron and Steel November 2007 TWIP 1 1 1 1, 2 1 熊荣刚 , 符仁钰 , 黎 倩 , 张 梅 , 李 麟 ( 1. , 200072; 2. , 200122) : 5 TWIP : 5 Hollomond, 1 n , 4 n , n :, ; ;, ,,,TWIP : TWIP ; ; : T 142. 4 : A : 0449749X(2007) Tensile Strain Hardening Behaviour of TWIP Steels 1 1 1 1, 2 1 XION Ronggang , FU Renyu , LI Qian , ZHAN Mei , LI Lin ( 1. School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China; 2. Shanghai Huizhong Automotive Manufacturing Co. , Ltd. , Shanghai 200122, China) Abstract: The strain hardening behaviour of five TWIP steels with different Mn content was investigated by static tensile test and metallography. The results show that Hollomond relationship is inapplicable. The n value of No. 1 steel was increased first and then decreased with increasing true strain. However, the n value of other steels was in creased with increasing true strain. Moreover, for the same steel, the n value was increased with increasing strain rate. The micro mechanisms are: with the increase of Mn content, formation of the twin will gradually play a leading role. T here are many annealing twins before tension. With the development of deformation, many deformation twins are formed. The interaction between twins and dislocations are coordinated with strain hardening rate. Subsequent ly, the necking is delayed and the ability of uniform deformation is obtained. Key words: T WIP steel; strain hardening; deformation twins ,,