初始应变速率对00Cr22Ni5Mo3N双相不锈钢超塑性的影响

Effect of initial strain rate on superplasticity of 00Cr22Ni5Mo3N duplex stainless steel

对00Cr22Ni5Mo3N双相不锈钢经过固溶处理和冷轧变形后,在950℃下保温5min,以不同的初始应变速率进行恒温超塑性拉伸试验,研究初始应变速率对00Cr22Ni5Mo3N双相不锈钢超塑性的影响规律。计算m值并观察不同初始应变速率下拉断后的组织,研究m值和断后组织随初始应变速率的变化规律,揭示初始应变速率影响材料超塑性的原因。试验结果表明:初始应变速率较低时,材料的组织比较粗大,初始应变速率增大时,材料的组织变得细小均匀。随着初始应变速率的增大,材料的伸长率和m值呈现相同的变化趋势,都是先增大后减小,并在1.5×10-3 s-1时所取得最大值分别为1070%和0.65。

After solution treatment and cold rolling deformation of 00Cr22Ni5Mo3N, super plastic deformation was tested with different initial strain rates for 5 min insulation under 950 ℃. Effect of initial strain rate on the super-plasticity of 00Cr22Ni5Mo3N duplex stainless steel was researched. The m-value was calculated and the microstructure after the tensile test was observed,and the variation of m-value and microstructure along with the initial strain rate was studied. The results show that when the initial strain rate is low, the microstructure becomes coarsely, on the contrary, the microstructure becomes fine. When the initial strain rate increases, variations of elongation and the m-value show the same tendency which increase first and then decrease. When the initial strain rate is 1.5×10-3 s-1, the elongation and the m-value achieve the maximum value of 1070% and 0.65 respectively.