316Ti不锈钢环境敏感断裂起裂时间研究

STUDY ON ENVIRONMENT SENSITIVE CRACKING TIME FOR 316Ti STAINLESS STEEL

采用慢应变速率（ＳＳＲＴ）和恒载荷（ＣＬＴ）试验方法，研究在压水堆（ＰＷＲ）一次侧工况下氯离子浓度、氧浓度、加载应力和应变速率对ＰＷＲ压力边界材料３１６Ｔｉ不锈钢环境促进起裂时间的影响。试验结果表明：起裂时间τ的对数ｌｇτ与载荷σ的对数ｌｇσ和Ｃｌ－浓度的对数ｌｇω（Ｃｌ－）皆呈良好的线性关系；产生应力腐蚀破裂（ＳＣＣ）的阈值应力与Ｃｌ－浓度和应变速率有关，随着Ｃｌ－浓度和应变速率的提高，阈值应力降低。

The time of environmentally assisted cracking of 316Ti stainless steel is studied by slow strain rate test (SSRT) and constant load test (CLT) methods The experimental results under the simulating water chemical conditions of PWR primary side show that the initial fracture time τ deponds on the concentration of Cl - ion w (Cl -) and the load σ The relationships between lg τ and lg w (Cl -), Δlg τ and Δ σ are all linear The threshold of stress corrosion cracking (SCC) is decreased with the increasing of w (Cl -) and σ