利用脉冲激光辐照研究超高温度梯度下表层预置ＺｒＯ２纳米颗粒涂层的 １８－８奥氏体不锈钢的快凝组织形态、微结构特征及力学性质，结果表明，在表层约１５μｍ范围内形成Ｚｒ的合金化微区， Ｚｒ最大含量（原子分数）为４３．３％，但Ｚｒ成分分布存在不连续特征；预置纳米 ＺｒＯ２陶瓷涂层明显提高了激光作用深度．超高温度梯度和高冷却速率显著细化了快凝亚组织并得到超细枝晶及胞晶，并观察到位错胞及栅栏李晶两类亚晶，而激光熔区的外延生长机制未使晶粒细化．激光辐照后，合金化区硬度增加而弹性模量降低，其余部分硬度增加而弹性模量无变化． The pulsed laser irradiation was used to study the fast-solidified microstructure and microstructure of 18-8 austenitic stainless steel with ZrO2 nano-particles coated on the surface under ultra-high temperature gradient. The results showed that the formation of Zr, the maximum content of Zr (atomic fraction) is 43.3%, but there is discontinuity in the distribution of Zr. The pre-impregnated ZrO2 ceramic coating significantly increases the depth of laser action. The ultra-high temperature gradient and high cooling rate remarkably refined the fast-setting sub-structure and obtained ultrafine dendrites and cell crystals, and dislocation cells and two types of barrier Li Jing sub-crystals were observed. However, the epitaxial growth mechanism of the laser melt zone did not make Grain Refinement. After laser irradiation, the hardness of the alloying zone increases while the elastic modulus decreases, while the remaining part of the hardness increases while the elastic modulus does not change.