针对N08810镍基合金焊缝超声检测时信号衰减严重, 信噪比低, 从而影响缺陷的判定及定位、定量等难题进行了分析,并对该镍基合金焊缝超声检测用的探头、对比试块、信噪比及DAC曲线作了探讨。结果表明, 研制的纵波双晶斜探头在粗晶N08810镍基合金焊缝的超声检测中效果明显, 提高了检测信噪比及缺陷检出率,自行设计、加工制作的镍基合金焊缝对比试块符合检测要求, 并对N08810镍基合金焊缝超声检测工艺进行了可检性评价, 该工艺在工程实践中得到了应用, 并取得了良好的效果。

Aiming at the ultrasonic inspection of N08810 nickel-based alloy weld, analysis is made on its severe attenuation and low signal-to-noise ratio, which affects the defect judgment, positioning and quantitative evaluation. At the same time the probe, the test blocks for ultrasonic inspection of the nickel-based alloy weld, the signal to noise ratio and the DAC curve are also discussed. The results showed that longitudinal twin oblique angle beam probe (TRL) developed obvious was effective in ultrasonic testing of welds N08810 nickel-based alloy of coarse-grained material and it improved the signal-to-noise ratio and the defect detection rate. Our self-designed and manufactured test block can meet the detection requirements. Finally, the detection process of ultrasonic N08810 weld is summarized; the technology has been applied in engineering practice and achieved good results.