激光喷丸处理是一种新型的材料表面强化技术，能够提高不锈钢的耐点蚀性能。但目前缺乏激光喷丸后奥氏体不锈钢的点蚀早期行为研究。本项目以304不锈钢为研究对象，拟采用微电极技术研究激光喷丸后表面微观结构的变化对其亚稳点蚀形核及生长的影响。采用FIB-SEM、TEM和XPS等多种实验手段对激光喷丸后奥氏体不锈钢的微观结构和成分进行表征，并与不同极化电位下亚稳点蚀暂态数目及特征参数的统计结果进行对比，揭示亚稳点蚀的萌生机理。对单个暂态生长动力学进行分析，建立亚稳蚀坑的生长速率与极化电位的关系，揭示亚稳点蚀的生长机制；进一步建立峰值暂态电流密度与半球形蚀坑半径的乘积（ipit·rpit）与激光脉冲功率密度/喷丸次数/脉冲宽度参数的关系，定量揭示激光喷丸奥氏体不锈钢亚稳点蚀向稳态点蚀转变的倾向性，为激光喷丸工艺参数的优化提供科学依据。

Laser shock peening (LSP) is a new surface-hardening treatment which can improve the pitting corrosion resistance of stainless steels. To date, the pitting initiation and metastable growth are not completely understood for austenite stainless steel after LSP. Therefore, in this project, the relationship between the change of the microstructure for 304 stainless steel after LSP and its metastable pitting behaviour will be investigated by using microelectrode technique. The current transients will be recorded by applying various constant potentials. By comparing the transient analysis with the defect characterization using SEM, TEM and XPS et al. statistically, a corresponding relationship between the metastable pitting and microstructure can be established. Moreover, the growth mechanism of metastable pitting will be discussed considering the changing law of transient growing rate with applied potentials and single current transient analysis. In addition, by developing an experimental formula between the main technological parameters of LSP and ipit·rpit, an optimal process of LSP should be proposed expectantly to improve the pitting corrosion resistance.