冷加工对CN-1515奥氏体不锈钢包壳管亚结构的影响

Effect of Cold Processing on the Substructure of CN-1515 Austenitic Stainless Steel Cladding Tube

通过透射电镜(TEM)和背散射电子衍射(EBSD)对冷加工后CN-1515奥氏体不锈钢包壳管亚结构的演变规律进行研究。结果表明,随着冷轧变形量的提高,退火孪晶减少,形变孪晶数量逐渐增大,孪晶宽度和孪晶间距不断变小,孪晶宽度由变形量为15%时的0.03~0.043μm减小到25%时的<0.02μm,而位错胞的尺寸则呈现先变大后变小的趋势。另外,冷轧工艺条件下,形变孪晶的形态也是一直保持平直,冷拔时出现孪晶界的弯折。在相同变形量下,冷拔比冷轧会产生更多的形变孪晶。

The evolution law of substructure of CN-1515 austenitic stainless steel cladding tube after cold processing was studied by TEM(Transmission Electron Microscope)and EBSD(Electron Back-Scattered Diffraction).It showed that with the increase of cold rolling deformation,the annealing twins were reduced,the number of deformation twins was gradually increased,the twinning width and the twin spacing were continuously smaller,and the twin width was reduced from 0.03-0.043μm to<0.02μm when the deformation was at 15%and 25%,while the size of dislocation cells tended to become larger first and then smaller.In addition,the morphology of deformed twins kept straight all the time under cold rolling conditions,and twin boundary bending occurred during cold drawing.Under the same amount of deformation,more deformation twins would be produced in cold drawing than in cold rolling.