应变强化奥氏体不锈钢的低温冲击韧性

Cryogenic Impact Toughness of Strain Strengthened Austenitic Stainless Steel

对S30408和S31603奥氏体不锈钢在室温下进行不同应变量10%~20%的应变强化处理,然后分别在常温至-269℃进行低温冲击试验,研究了应变量对试验钢低温冲击韧性的影响。结果表明：两种钢的冲击韧性随着应变量的增大逐渐降低,应变强化后两种试验钢冲击吸收能随着试验温度的降低而逐渐降低,当温度低于-196℃（77 K）后冲击吸收能趋于平缓,呈现出＂平台＂;两种钢经过20%应变量强化后低温韧性仍较好,能够满足奥氏体不锈钢应变强化技术标准中低温冲击韧性指标要求。

S30408 and S31603 austenitic stainless steel were strengthened with different strain degrees 10%-20% at room temperature. The effect of stain degree on cryogenic impact toughness of austenitic stainless steel was investigated through impact tests from room temperature to-269 ℃. The results show that impact toughness of two steels decreased with increasing stain degree. The impact absorbed energy of S30408 steel and S31603 steel after strain strengthening decreased with the decrease of temperature. When the temperature was lower than-196 ℃（77K）, the impact absorbed energy became stable showing a platform. Both austenitic stainless steels had good cryogenic toughness after strain strengthening in large stain degree（20%）, which could conform to the requirements in technical standards.