镍基合金800H的腐蚀性能研究  

Corrosion Behavior of Nickel Base Alloy 800H in Hightemperature and High-pressured Water

作　　者：沈朝[1] 吴恋恋 张乐福[1] 段振刚[1] 孙耀[1] 

机构地区：[1]上海交通大学核科学与工程学院,上海200240

出　　处：《腐蚀科学与防护技术》2014年第2期113-118,共6页Corrosion Science and Protection Technology

摘　　要：研究了镍基合金800H在550℃,25 MPa,600℃,25 MPa和650℃,25 MPa超临界水中的应力腐蚀开裂敏感性,及其在超临界650℃,25 MPa,次临界290℃,15.2 MPa水中的均匀腐蚀性能,同时研究了其在空气中不同温度条件下的机械强度。通过慢应变速率拉伸实验得到相应的应力-应变曲线。结果表明,随着温度的升高,800H的机械强度逐渐下降;SEM像表明800H在这3种工况下均具有应力腐蚀开裂的倾向。由其在空气中不同温度下的机械强度可知,其屈服强度和抗拉强度基本上随温度的升高而降低。800H在超临界水条件下的腐蚀实验表明,其腐蚀增重大致符合抛物线增长规律;而其在次临界条件下的腐蚀却呈现出减重的特征。Susceptibility to stress corrosion cracking （SCC） of nickel based alloy 800H was studied in supercritical water at 550 ℃, 25 MPa, 600 ℃, 25 MPa and 650 ℃, 25 MPa respectively, and its general corrosion behavior in supercritical water at 650 ℃, 25 MPa and in subcritical water at 290 ℃, 15.2 MPa respectively as well. The mechanical properties of alloy 800H were also exam- ined at different temperatures in air. The strain-stress curve of slow strain rate tensile （SSRT） tests shows that the strength of alloy 800H decreases as temperature increases. The ex situ scanning elec- tron microscopy （SEM） observation shows that alloy 800H under the three conditions in supercriti- cal water all exhibits susceptibility to SCC. The SSRT tests in air show that the yield strength and tensile strength of alloy 800H decrease as temperature rises. The results of general corrosion experi- ment in supercritical waters show that the weight gain of the alloy follows a parabolic law; howev- er, in subcritical water the alloy exhibits mass loss.

关 键 词：超临界 次临界 慢应变速率拉伸 应力-应变曲线 应力腐蚀开裂倾向 

分 类 号：TG172[金属学及工艺—金属表面处理]