热轧工艺对409L铁素体不锈钢深冲性的影响

对含有单一柱状晶的409L铁素体不锈钢连铸坯,采用不同终轧温度的热轧工艺,由常规热轧转变为温轧,再经过相同后续工艺;较低终轧温度的成品获得了较高rm值和较低△r值.终轧温度的降低使组织演变发生变化:热轧和冷轧组织中晶界和晶内剪切带增多,变形组织被细化、硬化,尤其是中心层附近的粗大带状晶粒;两者的增多又增加了退火过程中的...

Effect of Hot Rolling Process on Deep Drawability of 409L Ferritic Stainless Steel

Continuous-casting slabs with pure columnar grains of 409L ferritic stainless steel were hot rolled at different finishing temperatures(FT),i.e.the conventional hot rolling was transformed into warm rolling,then the same subsequent process was conducted.The results showed that the finished sheet rolled at lower FT has greater rm value and smaller Δr value.The decreased FT causes some variations in microstructural evolution as follows.In either hot or cold rolled sheets,the grain boundaries and in-grain shear bands increase to refine and harden the deformed microstructure,especially the coarse banded grains around mid-thickness layer.Then the nucleation sites due to recrystallization during annealing increase so as to refine and homogenize the annealed microstructure.Meanwhile,the textural evolution thus varies,such as the texture after hot rolling and annealing moves from {001～114}〈110〉 to the regions with greater φ1 and Φ angles;the texture peak after cold rolling shifts from {001}〈110〉 to {335}〈110〉;the γ-fiber texture after cold rolling and annealing increases and the peak shifts from {334}〈483〉 to {111}〈112〉,while the {001～114}〈110〉 and(0°<Φ<35°,φ1≈25°) textures decrease.