为揭示激光离散预处理对镀铬身管的延寿机制,研究了激光离散预处理钢基铬层的功能梯度界面(FGI)效应。结果表明,激光离散预处理使钢基体表层形成周期性梯度结构,初始镀铬层遗传了激光离散预处理基体表层的周期性梯度组织特征。FGI层因激光离散预处理在钢基体/铬层间形成,该FGI层可降低基体/铬层间的硬度梯度,大幅提高铬层的抗腐蚀剥落能力。 In order to reveal the mechanism of laser lifetime extension of chrome plated barrel by discrete laser pretreatment, the function gradient interface (FGI) effect of laser pretreatment of chromium matrix was studied. The results show that the laser gradient pretreatment makes the surface of the steel matrix form a periodic gradient structure, and the initial chrome plating layer inherits the periodic gradient structure characteristics of the laser surface pretreatment matrix. The FGI layer is formed by a laser discrete pre-treatment between the steel substrate / chrome layer. This FGI layer can reduce the hardness gradient between the substrate / chrome layer and greatly improve the corrosion resistance of the chrome layer.