摘要
针对奥氏体钢焊缝超声探伤时衰减严重，结构噪声显著，信噪比低，影响缺陷的定位、定量等难题进行了分析。以典型的9％Ni粗晶奥氏体钢焊缝为研究对象，在分析窄脉冲降低噪声的原理基础上，采用提高背衬阻抗和电路匹配的方式制作出1～1．5个周期的窄脉冲斜探头。结果表明，与普通斜探头相比，研制的窄脉冲斜探头在9％Ni奥氏体钢焊缝超声波探伤中降噪效果明显，有效地提高了探伤的信噪比。
It is difficult to inspect austenitic steel and their welds by ultrasonic test because of severe attenuation,structure noise,low signal-to-noise ratio(SNR)and low defect detection rate.In this paper,the typical 9% Ni coarse grain austenic steel and their welds were used as the studied object.The narrow pulsed oblique probe with 1-1.5 cycles was prepared by increasing high backing impedance and circuit matching based on narrow pulsed noise reduction theory.The results show that,compared with common oblique probe,the narrow pulsed oblique probes have better noise reduction and effectively improve SNR in ultrasonic inspection for austenitic steel and their welds.
出处
《焊接》
北大核心
2008年第6期52-55,共4页
Welding & Joining
关键词
粗晶组织
信噪比
窄脉冲
coarse grain structure, SNR(signal to noise ratios), narrow pulse
