Abstract：The evolutions of Vickers hardness， microstructure and precipitates in Ti and V microalloyed martensite steels with different tempering time at 600 ℃ were studied by Vickers， OM and TEM. Moreover， the precipitation kinetics of precipitates in martensite steels was calculated using the existing methods. The results showed that hardness of two steels firstly decreased， then increased and finally decreased with the prolonging of tempering time at 600 ℃. The peak hardness of both steel was observed after tempering for 1 h. Besides， the hardness of Ti-steel was always higher than that of V-steel in tempering process. It was found that the decrease of hardness at the beginning stage was due to the decrease of dislocation density. The precipitation of MC phase played the role of precipitation strengthening effect， leading to the increase of hardness to the peak value. With the prolonging of tempering time， the hardness decreased again due to the coarsening of MC phase and the recovery of matrix microstructure. Since the precipitation kinetics of Ti-steel was faster than that of V-steel and its coarsening rate was slower， the effect of precipitation strengthening and the restraint of matrix recovery in Ti-steel were more obvious than those in V-steel. As a result， the hardness of Ti-steel was always higher than that of V-steel in tempering process.
康俊雨，孙新军，李昭东，雍岐龙. TiC和VC在低碳马氏体钢回火中的析出和粗化[J]. 钢铁, 2015, 50(10): 64-70.
KANG Jun-yu，SUN Xin-jun，LI Zhao-dong，YONG Qi-long. Precipitation and coarsening of TiC and VC in tempering process of low carbon martensite steels. Iron and Steel, 2015, 50(10): 64-70.
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2015, Vol. 50 
