钢恒温超塑焊接过程中原子的动态扩散行为

Dynamic diffusion behavior of atoms in isothermal superplastic welding process of steel

通过对40Cr/T10A钢试样待焊面表层实施组织超细化预处理,借助于电子探针仪现代理化检测手段和最小二乘法数学分析方法,测试计算了40Cr/T10A钢恒温超塑焊接过程中置换扩散型Cr原子的动态扩散浓度分布曲线、动态扩散系数和动态扩散激活能.结果表明,在40Cr/T10A钢恒温超塑焊接过程中,Cr原子的动态扩散激活能与晶界扩散激活能相近,扩散主要沿晶界进行,动态扩散系数比常规扩散提高两个数量级.

Through the ultra-fining pretreatment on the surface of 40Cr and T10A steels, the dynamic diffusion concentration distribution curves, dynamic diffusion coefficient and diffusion activation energy of substitutional atom Cr in the isothermal superplastic welding process of both steels were measured and calculated by means of the electron probe of modern physical and chemical detection method and the least square method of mathematical analysis. The experimental results indicate that the dynamic diffusion activation energy of atom Cr in the isothermal superplastic welding process of 40Cr/T10A steels is closer to the activation energy of matrix phase grain boundary self-diffusion, and the atoms at two sides of interface mostly diffuse through the grain boundary, in which the dynamic diffusion coefficient of atom Cr has increased by two orders of magnitude comparison with conventional diffusion.