C和N含量及终锻温度对38MnVS6性能和组织的影响

摘要：通过显微组织定量统计、高分辨透射电镜及热力学计算等手段，研究了成分微调及终锻温度对38MnVS6非调质钢力学性能和显微组织的影响。结果表明，通过降C增N处理和降低终锻温度，实验钢屈服强度得到一定提高，塑韧性得到明显改善，室温冲击功由52J增加至83J。其作用机制为降C使铁素体体积分数增加,塑韧性得到改善；而增N后提高了钢的析出强化作用，弥补降C带来的强度损失；随着终锻温度的降低，铁素体数量增加且尺寸减小，细晶强化及韧化作用得到进一步提高。两方面综合作用使得实验钢强度保持稳定，而冲击韧性提高。

Effect of C and N contents and final forging temperature on mechanical properties and microstructure of 38MnVS6 steel

By the method of quantitative analysis of the microstructure, high resolution transmission electron microscopy and thermo dynamical calculation, the effect of adjustment of micro composition and final forging temperature on mechanical properties and microstructure of 38MnVS6 steel was studied. As the results showed, by lowering the content of carbon and adding the content of nitrogen, the strength could be increased while plasticity and toughness could be improved obviously. And the room temperature impact energy increased from 52 to 83J. The mechanism was that the drop in carbon content resulted in the increase in volume fraction of ferrite which enhance the toughness; the addition of nitrogen content could increase the precipitation strengthening effect, which made up the strength loss by carbon drop; and with the decrease in final forging temperature, the grain refined strengthening and toughening effects were improved by the grain refinement of ferrite and the increasing in ferrite percentage. The combination of adjustment of content and final forging temperature made the strength stay at a stable level and the toughness be improved.