四通道多频涡流定量评价曲轴圆角疲劳裂纹深度的试验研究

Experimental Research on Quantitative Evaluation of Fatigue Crack Depth in Crankpin Fillets by Four-Channel Multi-Frequency Eddy Current Testing

再制造前曲轴圆角疲劳裂纹扩展深度是影响其剩余疲劳寿命的重要因素,采用无损评估方法评价圆角疲劳裂纹扩展深度对于再制造前曲轴的质量控制至关重要.根据曲轴圆角的几何特征,应用多频涡流技术结合曲轴四通道涡流检测探头对圆角疲劳裂纹扩展深度进行定量评价.结果表明:多频涡流信号幅值的变化可以准确判断裂纹位置,进而可根据多频涡流信号的幅值反演裂纹的深度信息,为再制造前曲轴的质量控制提供依据.

Fatigue crack depth in crankpin fillets of crankshaft remanufacturing core is the key factor to influence its remaining fatigue life. Thus it is important to evaluate fatigue crack depth in crankpin fillets based on non-destructive test technology for quality control of crankshaft remanufacturing core. According to the geometric features of crankpin fillets, multi-frequency eddy current testing combined with four-channel multi-frequency eddy current testing probe for crankshaft is used to quantitatively evaluate fatigue crack depth. The results show that the location of cracks could be accurately determined by the variation of signal peak of multi- frequency eddy current testing and then the information of crack depth could be inversed according to the signal peak, hence provide evidence for quality control of crankshaft remanufacturing core.