【摘要】 本文研究了T91钢高温时效过程中组织和力学性能演变规律;并通过高温持久强度试验,探讨不同组织样品的应力-时间关系,揭示显微组织与持久强度之间的关系,并给出剩余寿命分析公式。结果表明,T91钢在高温时效过程中板条马氏体退化为等轴铁素体,位错减少,M₂₃C₆、MX型碳化物开始析出长大。M₂₃C₆粗化以及板条马氏体结构退化是T91钢持久性能下降的主要因素。更多还原

【Abstract】 In this paper,the correlation between the evaluation of microstructure and mechanical properties for the T91 steel high temperature aging process were studied. By performing high temperature durability strength test,the relationships of stress and time of samples with different tissues were explored,the relationship between microstructure and lasting strength was revealed and residual life analysis formula was derived. The results show that high temperature aging of T91 steel displays the lath martensite degradation into equiaxed ferrite,decrease of dislocation,precipitation of M₂₃C₆ and MX and grow up. In summary,M₂₃C₆ coarsening and lath martensite structure degradation are main factor causing the reduction of durability performance of the T91 steel.更多还原