The carbide precipitation was analyzed during aging of 2.25Cr–1Mo steel at 550 °C. The as-received steel was aged in two different manners: the first treatment was an isothermal aging at 550 °C for time up to 1000 h, and the second one was carried out by a cyclical aging, which consisted of aging at 550 °C for 1 h, water quenching at room temperature and then newly heating at 550 °C. This procedure was repeated up to 300 times. The M₂₃C₆ and M₆C carbide precipitation took place intragranularly and intergranularly for both aging treatments. The carbide coarsening was detected to occur with the increasing aging time. Nevertheless, the growth kinetics of precipitation occurred more rapidly in the case of cyclical aging. The specimen hardness decreased with the aging time in both cases; however, it occurred in shorter aging time for the cyclical aging. Nanoindentation testing indicated the increase in ductility with the aging time, and the cyclically aged specimens showed larger ductility than the isothermally aged specimens.

分析了2.25Cr-1Mo钢在550°C时效期间的碳化物沉淀。接收到的钢以两种不同的方式进行时效处理：第一种处理是在550°C下进行等温时效长达1000小时，第二种处理是通过周期性时效进行，其中包括在550°C时效进行时效。保持1小时，在室温下用水淬灭，然后在550°C下重新加热。重复该过程多达300次。M ₂₃ C ₆和M ₆在两种时效处理中，碳化物的沉淀都发生在晶内和晶间。随着时效时间的增加，发现碳化物粗大化。然而，在周期性老化的情况下，沉淀的生长动力学发生得更快。两种情况下，试样的硬度均随着时效时间的延长而降低。但是，它的循环时效时间较短。纳米压痕测试表明，延展性随时效时间的增加而增加，而周期性时效的试样则比等温时效的试样具有更大的延展性。