基体性质对含涂层系统压痕响应的影响

Effect of Substrate Performance on the Indentation Response of Coated Systems

对涂层／基体系统中，基体性质对涂层压痕力学行为的影响进行了研究，得出了基体对压痕载荷位移曲线的影响规律。研究表明：在给定的条件下，当压痕位移为涂层厚度的12％～16％时，由于基体屈服强度的变化，导致压痕载荷位移曲线在此处发生偏离；在压痕位移小于涂层厚度的10％时，不同的基体屈服强度得到的压痕响应完全一致，即基体的改变对压痕响应的影响是可以忽略的；同时还发现，在压痕位移为涂层厚度的30％时，如果基体屈服强度小于2000MPa时，基体屈服应力的改变会改变涂层的压痕力学行为，而当基体屈服强度大于2000MPa时，即使继续增大基体的屈服应力，所得到的载荷-位移曲线几乎重合，即其影响可以忽略。

The indentation response of coating-substrate is investigated using finite element analyses. The effect of substrate＇s yield strength on load-displacement curve is revealed. On the certain conditions, these load-depth curves present deviation at 12% -16% of coating thickness. The results showed that substrate＇s properties have a negligible effect on the indentation response when indentation displacement is less than 10% thickness of coating. Otherwise, the substrate＇s plastic deformation can have serious influence. Meanwhile, this paper revealed that while yield stress is less than 2000MPa, the increasing in substrate＇s yield stress can influence indentation response; on the contrary, if yield stress of the substrate is higher than 2000MPa, load-displacement curve has no change when altering substrate＇s yield strength.