采用316L奥氏体不锈钢小尺寸试样进行预研制，初步确定了预制大尺寸试样应力腐蚀裂纹的参数。结果表明：3.5%（质量分数） NaCl溶液，-1.2 V （相对于SCE）外加电位，降低应变速率，并延长极化作用时间有利于应力腐蚀的发生，且降低断后伸长率。在此基础上，100 kN保载24 d后，以0.5×10^-6 s^-1应变速率进行慢应变速率试验，可在大尺寸试样上成功制得长度超过25 mm的裂纹，且大尺寸试样的断后伸长率仅为12%。

316L austenitic stainless steel small-size sample was pre-developed, and the stress corrosion cracking parameters of prefabricated large-size sample was preliminarily determined. The results showed that 3.5% (mass fraction) NaCl solution, -1.2 V (vs. SCE) applied potential, reducing the strain rate and prolonging the polarization time were conducive to the occurrence of stress corrosion and reduced the elongation after fracture. On this basis, after a holding load of 100 kN for 24 d, a slow strain rate test was carried out at a strain rate of 0.5×10^-6 s^-1, and a crack with a length of more than 25 mm could be successfully produced on a large-size sample. And the elongation after fracture of the large size sample was only 12%.