中文摘要：

对普通铸态粗晶304不锈钢（CP—SS304）进行深度轧制，制备出纳米晶304不锈钢（BN—SS304）板材，将两试样经过同种磨削加工后在室温下恒速率拉伸．通过激光共聚焦显微镜对断裂试样不同位置表面轮廓的观察，得到试样断口附近和夹持端的表面粗糙度．结果表明，拉伸断裂后BN—SS304在任一位置的粗糙度均小于CP—SS304．越靠近断口，表面粗糙度越大，且BN—SS304在断口附近表面粗糙度增幅较大．

英文摘要：

Bulk nanocrystalline 304 stainless steel （BN -SS304 ） was prepared by severe rolling technique with its conventional polycrystalline counterpart （ CP - SS304 ）. The two samples for tensile test were processed by the same grinding method, and the tensile test with a constant rate was carried out at room temperature. The surface roughness near the fracture and the gripped end was obtained by the observation of the fracture surface profile in different positions with laser scanning confocal microscopy. The results show that the values of roughness of BN-SS304 at any position are less than those of CP-SS304 after tensile test. The closer to the fracture, the greater the surface roughness is. The values of surface roughness of BN-SS304 near the fracture increase more than those of CP-SS304.