2.25Cr1Mo传热管切向微动磨损性能研究

Study on Tangential Fretting Abrasion Performance of 2.25Cr1Mo Heat Transfer Tubes

钠冷快堆换热器中的冷却剂与构件之间的流致振动会导致传热管发生微动磨损。以钠冷快堆换热器传热管候选材料2.25Cr1Mo钢为研究对象,研究其在不同法向载荷(10、20、30 N)下的切向微动磨损行为和损伤演变规律;采用光学显微镜(OM)、扫描电镜(SEM)及EDS对磨痕的形貌及摩擦化学反应进行分析;通过白光干涉仪获得传热管的磨损量。结果表明:随着法向载荷的增加,2.25Cr1Mo钢的微动模式由完全滑移转变为部分滑移,摩擦因数、磨损体积随着法向载荷的增加先增加后减小;当载荷为10~20 N时,2.25Cr1Mo钢的主要磨损机制为磨粒磨损、分层剥落以及氧化磨损,当载荷为30 N时,主要磨损机制为黏着磨损、塑性变形和氧化磨损。

In sodium-cooled fast reactors,the flow-induced vibration between the coolant and components in the heat exchanger can cause fretting wear of the heat transfer tubes.2.25Cr1Mo steel,a candidate material for the heat transfer tube of the fourth-generation sodium-cooled fast reactor,was taken as the research object.The tangential fretting wear behavior and damage evolution of 2.25Cr1Mo steel under different normal loads(10 N,20 N,30 N)were studied.Optical microscope(OM),scanning electron microscope(SEM)and EDS were used to analyze the tribo-chemical reaction of the wear scar and the composition of local micro-area,and the wear volume of the 2.25Cr1Mo steel was obtained by a white light interferometer.The results show that with the increase of normal load,the fretting mode of 2.25Cr1Mo steel changes from full slip to partial slip.The friction coefficient and the wear volume first increase and then decrease with the increase of the normal load.When the load is from 10 N to 20 N,the main wear mechanisms of 2.25Cr1Mo steel are abrasive wear,delamination and oxidative wear,when the load is 30 N,the main wear mechanisms are adhesive wear,plastic deformation and oxidative wear.