热处理对45CrNiMoV钢析出相和力学性能影响  

Effect of heat treatment on precipitate and mechanical properties of 45CrNiMoV steel

作　　者：徐盛[1] 刘雅政[1] 周乐育[1] 闫永明[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《材料热处理学报》2014年第3期127-132,共6页Transactions of Materials and Heat Treatment

摘　　要：通过扫描电镜(SEM)、透射电镜(TEM)观察及硬度、拉伸性能测试,利用正交实验方差分析,研究了不同回火温度对45CrNiMoV高强钢析出相形貌和力学性能的影响。结果表明,实验钢回火温度对强度和冲击功均有显著影响,550℃回火后强/硬度达到最高值,600℃以上回火强/硬度急剧下降;实验钢回火温度从570℃提高到640℃,析出的碳化物形貌由条杆状向球形演变,570℃回火后,析出的细小的球状碳化物对马氏体板条边界存在钉扎作用。640℃回火后,析出的碳化物已经无法钉扎住板条边界;实验钢最佳热处理工艺为880℃油淬保温45 min+590℃回火240 min。Effects of tempering temperatures on 45CrNiMoV high-strength steel precipitates and its property were investigated by means of scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, orthogonal experiments, hardness and tensile tests. The results show that the relatively significant effect of tempering temperatures on strength and impact energy is observed. Strength and hardness of the steel get to the peak value when tempered at 550 ℃. When the temperature is above 600 ℃, the strength of the steel sharply decreases. As tempering temperature increasing from 570 ℃ to 640 ℃ , the shape of the precipitates evolve from rod to sphere gradually. Fine carbides precipitates help to stabilize the remaining lath boundaries when tempered at 570 ℃. The coarsening of the carbide particles are ineffective pinning of the lath boundary when tempered at 640 ℃. The optimum heat treatment process of the steel is quenching at 880 ℃ for 45 rain in oil and tempering at 590 ℃ for 4 h.

关 键 词：45CrNiMoV钢 回火温度 力学性能 析出物 

分 类 号：TG142.41[一般工业技术—材料科学与工程]