摘要
利用慢应变速率试验,采用非标准的漏斗状试样,对国产690合金与321不锈钢异种金属焊接部位(包括690合金热影响区、焊缝、321不锈钢热影响区)在100 mg/L Cl^(-1)除O_2条件下和100 mg/L Cl^(-1)饱和O_2条件下的应力腐蚀行为进行研究。并通过慢应变速率应力-位移曲线和断口形貌对微观组织、氯离子、氧含量对于材料的应力腐蚀(SCC)的影响进行分析。结果表明:690合金热影响区在100 mg/L Cl^(-1)除O_2条件下不易发生SCC,在100 mg/L Cl^(-1)饱和O_2条件下表现出一定的SCC倾向;321不锈钢热影响区在2种条件下均表现出明显的SCC倾向;690合金热影响区的粗大晶粒不利于塑性变形的晶粒间相互协调,导致了热影响区SCC的倾向增大。
Stress corrosion cracking （SCC） behaviors of welded joint with inconel 690 and 321 stainless steel （including soldering seam, heat-affected zone of inconel 690 and heat-affected zone of 321 stainless steel） were studied through slow strain rate tension （SSRT） test under 100 mg/L Cl^-1 without O2 as well as 100 mg/L Cl^-1 with saturated O2. Effects of microstructure, chlorine ion and oxygen content on SCC behaviors of the materials were analyzed through SSRT stress-displacement curves and fracture morphology. It is found that the heat-affected zone （HAZ） ofinconel 690 is with low probability of SCC under 100 mg/L Cl^-1 without O2, and showed a certain degree of SCC tendency under 100 mg/L Cl^-1 with saturated O2, while HAZ of 321 stainless steel is with high probability of SCC under both conditions. The coarse grains of inconel 690 HAZ make against the intercoordination between grains during the plastic deformation, and reduce the strengthening and toughening of grain boundaries, and therefore, increase the SCC tendency of the HAZ.
出处
《核动力工程》
EI
CAS
CSCD
北大核心
2017年第4期153-158,共6页
Nuclear Power Engineering
