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以涡轮叶片用DZ125合金为研究对象,通过蠕变中断实验模拟涡轮叶片的服役损伤,并分别在1230,1240和1250℃进行恢复热处理,随后再次进行与恢复热处理前相同条件下的蠕变中断实验,对比研究了恢复热处理对DZ125合金蠕变退化组织与性能的影响.结果表明,DZ125合金在980℃,207 MPa条件下经蠕变中断实验与恢复热处理后,引发再结晶的临界应变量介于3.5%~10.0%之间.1230℃固溶热处理部分消除了合金在1.0%蠕变过程中形成的粗大g’相,导致其经2次时效处理后的基体组织中g’相大小不均匀,从而部分恢复其原有性能.固溶温度进一步提高至1240~1250℃,不仅消除了粗大g’相而且显著降低了残余共晶g’相含量,并在时效处理后获得均匀组织.因此,恢复热处理的效果得到显著提高,达到甚至超过原有性能.
Taking turbine blade DZ125 alloy as the research object, the service damage of the turbine blade was simulated by the creep interruption experiment and resumed to heat treatment at 1230, 1240 and 1250 ℃, respectively, and then the creep rupture experiment under the same condition as before recovery heat treatment , The effect of the recovery heat treatment on the creep degeneration structure and properties of DZ125 alloy was studied.The results show that the critical strain of recrystallization of DZ125 alloy after the creep rupture test and the recovery heat treatment at 980 ℃ and 207 MPa are between 3.5% ~ 10.0% .1200 ℃ solution heat treatment partially eliminates the coarse g ’phase formed during 1.0% creep of the alloy, resulting in uneven microstructure of g’ phase in the matrix after 2 aging treatments, Thereby partially recovering its original properties.The further increase of the solution temperature to 1240 ~ 1250 ℃ not only eliminated the coarse g ’phase but also significantly reduced the residual eutectic g’ phase content and obtained a uniform microstructure after aging treatment. The effect of heat treatment has been significantly improved to meet or exceed the original performance.