Nd:YAG晶体表面性能等离子体改性研究

Research on Surface Properties of Nd:YAG Crystal Modified by Plasma Jet

采用自行研制的常温等离子设备,开展等离子体射流对Nd:YAG晶体表面润湿性和表面力学性能的改性试验研究。结果表明:等离子体对Nd:YAG晶体表面具有明显的改性作用,等离子体改性后3种粗糙度特征的Nd:YAG表面润湿性均获得改善,其中光滑表面由疏水转变为超亲水,且在30 h内保持良好的亲水状态,改性后Nd:YAG晶体表面含氧官能团的增加是润湿性改善的主要原因;Nd:YAG晶体改性后0~11 h、11~22 h、22~35 h,显微硬度分别呈现出保持、下降与回复、稳定的特点,其中11~22 h内具有最低的表面显微硬度,在15.0、30.0、70.0 mN载荷作用下,其平均显微硬度分别下降了56.2%、45.0%、31.6%;改性后11 h,表面塑性的迅速提高导致部分压痕形貌出现“阶梯”和“阴影”特征。

The surface wettability and mechanical properties of Nd:YAG crystals were investigated to study the influence of plasma jet on Nd:YAG crystals by using self-developed plasma equipment at room temperature.The results show that the plasma has significant effects on surface properties of Nd:YAG crystals,and the wettability of Nd:YAG crystals with three different roughness is improved after plasma modification.Especially,the smooth surface changes from hydrophobic to super-hydrophilic,and the good state of hydrophilicity lasts 30 hours.The improvement of wettability of Nd:YAG surface mainly lies in the increase of oxygen-containing functional groups on the surface of the modified Nd:YAG crystals.The microhardness remains unchanged within 0 to 11 h,decreases first and then increases within 11 to 22 h,and remains stable within 22 to 35 h after the modification.Especially,a minimal microhardness occurs between 11 to 22 h after the modification.Under the peak load of 15.0,30.0 and 70.0 mN,the average microhardness decreases by 56.2%,45.0%and 31.6%,respectively.And the morphology of some indentations shows features of“ladder”and“shadow”due to the rapid increase of plasticity on Nd:YAG surface 11 hours after the modification.