车轴钢渗碳层深度弱磁检测技术研究

Research on Weak Magnetic Inspection of Axle Steel Carburizing Layer Depth

针对现有车轴钢渗碳层深度无损检测技术的工程局限性,提出一种弱磁检测方法,即利用渗碳层与其心部交界处应力集中且无法消除、进而对外表现出特定的磁感应强度的无损检测方法。通过采集不同样本车轴钢及其不同部位的磁场信号,分析磁感应强度幅值与深度的对应关系,构建弱磁检测数学模型。试验结果(标准厚度/检测厚度/绝对误差):花键外圆3.50 mm/3.57 mm/0.07 mm、杆部外圆4.30 mm/4.46 mm/0.16 mm、R角4.00 mm/3.86 mm/-0.14 mm,检测精度整体相对误差小于5%,满足工厂实际检测需求。

To deal with the limitation of the existing non-destructive testing technology for the depth of the carburized layer of axle steel,a weak magnetic detection method is proposed.Since the stress concentrates at the junction of the carburized layer and its heart and can't be eliminated,and then externally show a specific magnetic induction intensity for non.By collecting magnetic field signals from different samples of axle steel and different parts of axle steel,we analyzed the corresponding relationship between magnetic induction intensity amplitude and depth,and constructed a mathematical model for weak magnetic detection.The test results show that:spline outer circle(standard thickness/inspection thickness/absolute error):3.50 mm/3.57 mm/0.07 mm;rod outer circle:4.30 mm/4.46 mm/0.16 mm;R-angle:4.00 mm/3.86 mm/-0.14 mm.The overall relative error of the inspection accuracy is less than 5%,which meets the actual needs of the factory inspection.