论文部分内容阅读
为研究电站高温金属部件在高温应力作用下显微组织老化损伤程度的演化规律,设计了高温应力时效老化试验,对供货态T91钢在不同温度不同应力条件下进行高温时效老化.用金相显微镜、扫描电镜、透射电镜、定量金相和显微硬度等试验方法研究组织性能变化.结果表明,T91经不同温度老化后的微观组织随着温度和应力的升高,回火马氏体位向特征分散,晶界和晶内沉淀相粒子尺寸粗化,沉淀相颗粒Feret直径从原始供货态0.200μm增加到0.435μm.在相同温度下应力对组织老化的影响明显,马氏体板条内位错密度降低,板条亚结构退化,马氏体板条特征逐渐消失.随着温度的提高硬度呈现加速下降变化趋势,硬度的下降与析出相颗粒尺寸的增加同步变化,且变化趋势相似.
In order to study the evolvement law of aging damage degree of high temperature metal parts under high temperature stress, a high temperature stress aging aging test was designed to treat aged T91 steel under high temperature aging under different temperature and different stress. Microstructure, microstructure, microstructure, microstructure, microstructure and properties of T91 after aging at different temperatures with the increase of temperature and stress, the orientation of tempered martensite The grain size of the precipitated phase was broadened from the grain size of0.200μm to the original grain size of0.435μm. The effect of stress on the microstructure aging was obvious at the sametemperature, The density of dislocation decreases, the lath substructure deteriorates and the martensite lath disappears gradually. The hardness decreases with the increase of temperature, and the decrease of hardness changes synchronously with the increase of particle size of precipitation phase.