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 11h，decreases first and then increases within 11 to 22h，and remains stable within 22 to 35h 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. 0mN，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．