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以非线性表面波检测点蚀损伤为研究内容, 利用有限元模拟软件Abaqus CAE创建304不锈钢点蚀损伤非线性超声检测模型.由于传统信号处理方法在点蚀损伤非线性超声检测方面灵敏性较差, 提出用希尔伯特-黄变换方法对损伤定量表征.结果表明:边际谱中提取的非线性系数β可对点蚀早期损伤定量表征;相对于傅里叶变换, 基于HHT的非线性系数β对损伤变化更敏感, 展示了HHT方法在非线性超声检测点蚀早期损伤方面的优越性.“,”The nonlinear ultrasonic detection of pitting damage is taken as the research content in this paper.The computer simulation method is used to create a 304 stainless steel pitting corrosion nonlinear ultrasonic detection model by using the finite element simulation software Abaqus CAE.Due to the lack of sensitivity of traditional signal processing methods in the nonlinear ultrasonic detection of pitting damage, the Hilbert-Huang transform method is proposed to quantitatively characterize the damage.The results show that the nonlinear coefficientβextracted from the marginal spectrum can quantitatively characterize the early damage of pitting;and the nonlinear coefficientβbased on HHT is more sensitive to the damage than the Fourier transform.It shows that the superiority of the HHT method in nonlinear ultrasound detects of pitting damage.