高温氧化对30Cr1Mo1V钢蠕变-疲劳裂纹扩展速率的影响

摘要

Influence of oxidation on creep-fatique crack growth (CFCG) of 30CrlMolV steels has been studied in air or argon environment respectively at room temperature, 540 ℃ and 650 ℃. Results show that the CFCG rate increases obviously with reducing loading frequency at high temperatures in air environment. During loading process with different holding durations, the CFCG rate in air is obviously higher than in inert atmosphere, indicating that oxidation plays a role in effecting the crack growth. In inert atmopheres, the CFCG rate increases with rising holding time, whereas in air envrionment, when the holding time is more than 60 s, the CFCG rate rises linearlly with time, indicating that the crack growth is time-dependent this moment.%在室温、540℃和650℃下,分别研究了空气或氩气气氛中氧化对30Cr1Mo1V钢蠕变-疲劳裂纹扩展速率的影响.结果表明:在高温下,在空气中和加载频率较低时,30Cr1Mo1V钢的裂纹扩展速率均明显增加.在加载过程中引入保载时间,空气中30Cr1Mo1V钢的裂纹扩展速率明显高于惰性环境中,说明氧化影响着疲劳裂纹扩展行为.在惰性气氛中,裂纹扩展速率随保载时间的延长而增大.在空气中,当保载时间超过60 s时,裂纹扩展速率随时间呈线性比例增大,表明此时裂纹扩展行为与时间因素相关.