合金元素V对电力金具用低合金CrMo钢组织和力学性能的影响

Effects of Alloying Element V on Microstructure and Mechanical Properties of Low Alloy CrMo Steel for Power Fittings

通过热处理实验、力学性能检测、微观组织检测等方法,研究了合金元素V对电力金具用低合金CrMo钢组织和力学性能的影响。结果表明,随着V含量增加,退火后粒状贝氏体上M-A组元尺寸逐渐增大;回火保温过程中,M-A组元分解程度与V含量相关,V含量越高,M-A组元分解越不充分,同时晶界析出的M_(23)C_(6)越多。含V量越高,M-A组元分解越不充分,从而导致材料的强度升高,而M-A组元的不充分溶解以及M_(23)C_(6)在晶界、亚晶界析出并长大是导致含V量高的材料冲击性能下降的主要原因。

The effects of alloying element V on the microstructure and mechanical properties of low-alloy CrMo steel used for power fittings were contrastive by studied by mechanical property testing and microstructure observation. The results show that with the increase of V content, the size of M-A component on the granular bainite gradually increases after annealing. The decomposition degree of M-A component is related to the V content during tempering. The higher the V content, the more insufficient the decomposition of the M-A component, and the more M_(23)C_(6)precipitates at the grain boundary. The higher the V content, the more insufficient the decomposition of the M-A component result in an increase in the strength of the material. With the increase of V content, the insufficient dissolution of M-A components, the precipitation and growth of M_(23)C_(6)at the grain boundary and in the subcrystal boundary are the main reasons for the decline of the impact toughness of the material.