M50钢强流脉冲电子束Cr合金化的高温摩擦性能

Tribological Properties of Cr Alloying Layer on M50 Steel Induced by High Current Pulsed Electron Beam

结合磁控溅射与强流脉冲电子束辐照技术在M50钢表面制备了Cr合金化层。采用X-射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)对合金化层的组织结构进行表征分析,研究了Cr合金化层的高温摩擦行为及磨损机制.结果表明:Cr合金化层由表向内依次为Cr含量较高的体心立方(BCC)Fe-Cr固溶体、奥氏体和马氏体. M50钢与Cr合金化层的高温磨损机制均为氧化磨损。Cr合金化层高温摩擦系数在0.2～0.4之间,低于M50钢0.5～0.8,具有一定的自润滑效果. SEM和能谱分析表明:Cr合金化层在高温摩擦过程中优先生成与基体结合良好的低摩擦系数的氧化铬膜是其摩擦系数降低的主要因素.

High current pulsed electron beam combined with magnetron sputtering had been employed to fabricate Cr alloying layer on M50 steel.Scanning electron microscope,transmission electron microscope,and X-ray diffraction had been used to analyze the microstructure of the Cr alloying layer.The tribological properties and wear mechanism of the Cr alloying layer were studied.The results show that the Cr alloying layer possessed multi-layer characteristics.The Cr alloying layer was composed ofBCC Fe-Cr,γ phases and martensite.The wear mechanism of M50 steel and Cr alloying layer was oxidation wear.The friction coefficient of the Cr alloying layer was between 0.2-0.4,lower than that of M50 steel (0.5-0.8).The reason was the solid lubrication effect of the oxides and the good adherence between the oxides and Cr alloying layer which can be concluded by the results of scanning electron microscope and energy dispersive spectrometer.