镍铬镀层的裂纹缺陷是造成镀镍铬零件功能失效的主要原因，对此类零件最为有效的无损检测方法是亲水性后乳化的荧光渗透检测。如何选择乳化剂浓度、乳化时间等参数，是亲水性后乳化荧光渗透检测成功的关键。通过对镍铬镀层裂纹标准试片荧光渗透检测时在不同乳化时间、乳化剂浓度参数下进行的试验，选择较为合理的乳化参数，达到符合标准要求的检测灵敏度。

The crack defect of nickel chrome plating layer is the main cause of the part failure. For this type of part, the most effective nondestructive test method is fluorescence penetrant inspection-hydrophilic post emulsification method. How to choose the concentration of emulsifier and emulsifier time is the key to make the hydrophilic post emulsification succeed. Through testing on standard test piece of nickel chrome plating layer under different emulsifier time and emulsifier concentration, the proper emulsifier parameters were selected to reach the detection sensitivity complying with the requirement.