应变强化对奥氏体不锈钢高温疲劳行为的影响  

Effect of Cold Stretching on Fatigue Behavior of Austenitic Stainless Steel at Elevated Temperature

作　　者：韩豫[1] 王可胜[1] 刘全坤[2] 

机构地区：[1]宁波工程学院机械工程学院,宁波315016 [2]合肥工业大学材料科学与工程学院,合肥230009

出　　处：《机械工程学报》2013年第12期32-37,共6页Journal of Mechanical Engineering

基　　金：国家高技术研究发展计划(863计划;2009AA044802);浙江省自然科学基金(Y1111068);宁波市自然科学基金(2012A610055)资助项目

摘　　要：采用应变强化技术制造奥氏体不锈钢制压力容器可以使容器壁厚减薄,是实现压力容器轻型化设计的有效手段。为研究应变强化过程中容器的风险增量,对固溶态和应变强化预处理态的S31603奥氏体不锈钢在550℃、应力控制模式下的疲劳行为开展系统研究。研究结果表明,应变强化预处理前后材料均表现出持续的循环硬化响应,但经应变强化预处理后材料的循环应变幅和平均应变响应均小于固溶态材料;由于材料在试验温度下发生动态应变时效,其平均应变表现出突然阶跃行为,且应变强化前后材料出现平均应变阶跃次数大致相同;室温下不超过10%的应变强化预变形处理能有效提高材料的屈服强度,减小材料的循环应变幅响应,延长材料的高温疲劳寿命,从而为应变强化奥氏体不锈钢制容器在高温环境下的可靠运行提供保证。Cold stretching technique is an effective way to enable thinner wall thickness of the austenitic stainless pressure vessel and thus can achieve lightweight design. In order to investigate the risk increment of the cold stretched vessel, the fatigue behaviors of solution annealed（SA） and cold stretched（CS） S31603 austenitic stainless steel is systematic studied under stress controlling mode at 550 ℃. The results show that： Sustained cyclic hardening response is displayed for both SA and CS material, only the cyclic strain amplitude and mean strain response of CS material is lower than SA one. Abrupt jump of mean strain is found at 550℃ which could be attributed to the dynamic strain aging effects. The times of abrupt jump under different cyclic stress for both SA and CS materials are nearly the same. By comparing with the SA material, no more than 10% deformation of the CS material makes the yield strength enhance and the cyclic strain amplitude decrease, which contribute to improve the fatigue life of the material and provide guarantee for reliable operation of the cold stretched austenitic stainless pressure vessel at elevated temperature.

关 键 词：应变强化 奥氏体不锈钢 疲劳 高温 应力控制 

分 类 号：O346[理学—固体力学] TG142[理学—力学]