ZG35CrMo贝壳状断口及其对性能的影响

Behavior Influence of Fracture of Conchoidal ZG35CrMo

ZG35CrMo调质处理后出现的贝壳状断口大多表现为沿柱状枝晶界面发生的沿晶韧断。电弧炉熔炼Al终脱氧的ZG35CrMo,当其残Al量在0.022%以下时,贝壳状断口是由晶界面上析出的MnS、复合型硫氧化物以及元素偏聚造成的。钢中出现贝壳断口不影响其拉伸强度,但明显降低冲击韧性和断面收缩率,且与贝壳断口面积百分比间有如下关系: a_k(J/cm^2)=128.8-0.723△S_1(%);ψ_k(%)=44.59-3.76×10~2△S_2(%)-1.972×10^(-3)△S_2~2(%)。采用高温扩散退火及随后的热处理可改善或消除贝壳状断口,并可提高机械性能。单纯提高正火或回火温度。虽不能消除贝壳状断口,但也可改善机械性能。

The fracture of conchoidal ZG35CrMo show along columnar crystal face happened tough break.After modified treatment, ZG35CrMo can be melted by arc furnace A act as final deoxidizer.Conchoidal fracture consist of crystal surface separate out compound MnS oxysulphur and element segregation .It's not infulence fensile strength, but reduce impact toughness apparently and contraction of area, and with conchoidal fracture area percent have such relation:a_k(J/cm^2)=128.8-0.723△S_1(%); ψ_k(%)=44.59-3.76×10^(-2)△S_2(%)-1.972×10^(-3)△S_2~2(%).It's improve or eliminate conchoidal and raise mechanica behavior fracture, if introduce high temperture diffuse annealing and heat treatment. It improved mechanical behavior and can't eliminat eonchoidal fracture if simple raise treatment of normalizing or tempering.