基体性质对含涂层系统压痕响应的影响

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.

Effect of Substrate Performance on the Indentation Response of Coated Systems

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.