在役2.25Cr-1Mo钢不同氢含量条件下韧脆转变行为  

Ductile-brittle transition of 2. 25Cr-1Mo steel in service with different hydrogen contents

作　　者：王霄鑫[1] 张峥[1] 有移亮[1] 常波[1] 李鹏[1] 

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100191

出　　处：《材料热处理学报》2010年第10期58-62,共5页Transactions of Materials and Heat Treatment

基　　金：质检公益性行业科研专项资助;机械装备失效分析技术(200810411)

摘　　要：基于Charpy冲击实验研究加氢反应器用2.25Cr-1Mo钢长期高温服役后的回火脆化倾向。为了研究氢含量对该材料韧脆转变行为的影响,对已发生一定程度回火脆化的2.25Cr-1Mo钢进行电化学充氢处理,分别将试样氢浓度控制在2×10-6和4×10-6。对充氢后的试样进行Charpy冲击实验和慢速率拉伸试验,并对冲击断口形貌进行宏观与微观观察与分析。结果表明2.25Cr-1Mo钢长期高温服役后有较大的氢脆敏感性,充氢使2.25Cr-1Mo钢的韧脆转变温度升高,断口中出现沿晶断裂特征,且随着氢含量的增加,其韧脆转变温度持续升高,沿晶断裂特征所占比例增加。最后对2.25Cr-1Mo钢受回火脆与氢脆共同作用下的韧脆转变机理进行了探讨。The temper embrittlement tendency of 2.25Cr-1Mo steel after long term service at 427 ℃ was investigated based on charpy impact test.In order to analsyse the effect of hydrogen content on ductile-brittle transition of 2.25Cr-1Mo steel,specimens with temper embrittlement were electrochemically hydrogen charged.The hydrogen content in the specimen was controlled at 2 × 10-6 and 4 × 10-6,respectively.Charpy impact test and tensile test were conducted on the specimens with different hydrogen contents.The fracture surface of the specimens was examined.The results indicate that 2.25Cr-1Mo steel after long term service at 427 ℃ has large susceptibility to hydrogen embrittlement,the ductile-brittle transition temperature is increased by the hydrogen charged,and some intergranular fracture is observed on the fracture surface of these speciments.The ductile-brittle transition temperature continues to rise and the percentage of intergranular fracture increases with the increase of hydrogen content.The mechanism of ductile-brittle transition of 2.25Cr-1Mo steel under the interaction of temper embrittlement and hydrogen embrittlement was discussed as well.

关 键 词：2.25CR-1MO钢 回火脆 氢脆 叠加效应 

分 类 号：TG142.33[一般工业技术—材料科学与工程] TG113.25[金属学及工艺—金属材料]