【摘要】 从理论上分析了衰减对非线性超声测量值的影响,并根据实际检测条件提出了一种利用时域能量对衰减进行修正的方法。以不同蠕变状态的P91钢及其焊缝为检测对象,对比了衰减修正前后的非线性超声测量值,实验结果证明,在蠕变程度较高或衰减较大的条件下,该方法能够有效的修正衰减对非线性系数测量值的影响,应用该方法可以对P91及其焊缝的蠕变状态做出更为准确的评价。更多还原

【Abstract】 The distortion of nonlinear ultrasonic measurement caused by attenuation was analyzed theoretically.According to practical testing condition,an attenuation correcting method was suggested,which used time domain energy as a correcting parameter.To verify this attenuation correcting method,P91 steels and welds with different creep status were selected as inspection objectives in a testing experiment.Attenuation corrected and non-corrected nonlinear ultrasonic measurement results of different creep status were compared respectively.And the results show that while creep is well developed or attenuation is large,the suggested method can effectively correct the distortion of nonlinear ultrasonic measuring results caused by attenuation.In other words,this method can evaluate creep status of P91 steels and welds more accurately.更多还原