中文摘要：

有色金属零部件应用广泛,但已有的磁性检测方法均不能对其有效探伤。提出一种基于磁场测量的有色金属电磁探伤方法,在有色金属中通以直流电流,其体表会产生一个稳恒磁场,当有色金属表面或内部存在裂纹等缺陷时,有色金属体内电流分布发生变化,引起外部磁场变异,利用高灵敏度梯度磁场传感器测量磁场的畸变,可检出表面微小裂纹和内部缺陷。以铜板为例,建立了仿真模型,分析表面各个方向磁场分量的特征。实验结果表明：裂纹特征参数与测量磁场最大变化量间存在线性关系的结论,对有色金属探伤提供了新的方法。

英文摘要：

Non-ferrous metal components have been widely used,but present magnetic detection methods are not effective for their detection. A method for non-ferrous metal electromagnetic defect inspection based on magneticfield measurement is put forward. By introducing direct current to non-ferrous metal,a constant magnetic field will be excited on surface of non-ferrous metal. As cracks exist on surface or inside of non-ferrous metal,current distribution inside non-ferrous metal changes,which causes heteromorphosis of external magnetic field,so that tiny cracks on surface and inside defects can be detected by using gradient magnetic field sensor with high sensitivity. Taking copperplate as an example,simulation models are set up to analyze characteristics of magnetic field on surface in all directions. Results of experiment indicate that the maximum variation of measured magnetic field is linear relation to characteristic parameters of crack,which provides a new method for non-ferrous metal detection.