摩擦温度对Ni-P基复合刷镀层摩擦学性能的影响

Effect of Friction Temperature on the I ribological Properties of Ni-P Base Composite Brush Plating Layer

为了考察摩擦温度对Ni-P基复合镀层摩擦学性能的影响,作者按球-盘接触形式推导出了计算摩擦温度的数学表达式,其对Ni-P/WC和Ni-P/BN及Ni-P/MoS_2等几种复合镀层摩擦温度的计算结果与试样表面层的硬度分布显示了良好的对应性。磨损试验结果表明,特别在高PV值的情况下,Ni-P基复合镀层的摩擦学性能主要受摩擦温度的影响。这是因为Ni-P基复合镀层在镀态下呈非晶态组织,受热发生晶化反应后会使硬度上升,但温度过高时硬度却又下降。因此,镀层硬度是依摩擦温度的高低及其在镀层中的梯度分布而呈现出不同的分布特征,从而揭示了Ni-P/WC复合镀层在高PV值条件下显示良好固体润滑性能的原因。

In order to examine the effect of friction temperature on tribological properties of Ni-P base composite plating layer, a formula for calculating friction temperature was derived on the basis of ball-on-disc contact mode. The calculating results for several composite plating layers(Ni-P/WC, Ni-P/BN and Ni-P/MoSa) are in good agreement with the hardness distribution on surface of specimens. Especially, under the high PV value condition, the tribological behavior of Ni-P base composite plating layers is mainly controlled by friction temperature. This is due to that the Ni-P base composite plating layers present the amorphous structure in plating state, which can be crystallized after heat treatment with the increase of hardness, but when they are overheated their hardness will be decreased. Therefore, the composite plating layers show different hardness distribution along with the changes of friction temperature and its gradient distribution. Thus, the reason for Ni-P/WC composite plating layer presents good solid lubrication properties under high PV value condition can be revealed.