15CrMo钢珠光体球化对机械性能的影响

Effects of Pearlite Spheroidization in 15CrMo Steel on the Mechanical Properties

石油化工设备所用的铁素体－珠光体型耐热钢在长期高温条件下服役后，显微组织中的片状珠光体将转变成球化体。为搞清这种组织变化对机械性能造成的影响，选用石化设备常用的１５ＣｒＭｏ钢，对其进行了不同热处理工艺条件下的模拟球化退火处理，获得了不同的组织形态。对３种具有不同组织形态的试样进行了高温拉伸试验。结果表明，珠光体球化使钢的高温强度降低，尤其是高温屈服强度降低显著。球化程度愈严重，钢的高温强度愈低。该结果可为球化后的设备能否继续服役提供一定的参考依据。

When ferritic-pearlite refractory steels used for petrochemical plants for long time at high temperature, lameller pearlite in steels will be changed into sphericity. In order to understand effects of pearlite spheroidization on the mechanical properties, 15CrMo steel is selected and spheroidized annealing for different conditions, and tensile tests at elavated temperature have also been investigated for samples with different microstructures. The results show that pearlite spheroidization decreases the elavated temperature strengthes of this steel, especially yield strength. The more serious for pearlite to spheroldize is, the lower its strength is. This conclusion will provide scientific basis for whether spheroidized steel can be used.