中文摘要：

为了探究轴类零件内部缺陷的无损检测方法,本文以曲轴为研究对象,基于超声ALOK技术对其内部多个小孔进行了无损检测实验,并建立了相应的声学仿真有限元模型,提出利用声程—角度散点图中的趋势线,可快速判别内部缺陷特征和位置的方法。并且改进了ALOK算法,即采用邻近探头构建的方程或曲线重构缺陷,模拟和实验结果表明使用改进的算法提高了缺陷位置和尺寸的检测精度,通过实验数据重构所得的缺陷位置误差和半径误差分别在2 mm和0.5 mm左右。研究结论对于轴类零件内部缺陷精确定量化无损检测提供了理论和技术指导。

英文摘要：

A case study has been made on a crankshaft to nondestructively detect its internal defects. Several artificial holes ofФ 2 mm have been fabricated in the crankshaft and the test has been conducted based on the ultrasonic ALOK technology, and the acoustics simulation has been completed. A method that can quickly judge the feature and the position of internal defects is proposed based on the trend lines in the sound distance- angle scatter diagram. In addition, the ALOK algorithm is amended through adopting the equations or curves established by adjacent probes to reconstruct the defects. The results of simulations and experiments show that the amended algorithm can improve the detection precision of positions and dimensions. The errors of the position and radius of defects reconstructed through experimental data are about 2 mm and 0.5 ram, respectively. The research provides the theory and technical guidance for the quantitative and nondestructive test of internal defects in shaft parts.