通过对比国内外超声检测标准关于对比试块声学性能的规定，认为用声速和超声衰减表征材料的声学性能比较合适；介绍了对比试块和被检工件声速、材质衰减系数的测定方法，并分别测试钢板轧制方向和垂直于轧制方向的声速、材料衰减系数，测试结果表明常用钢板中的各向异性对声速、衰减系数的影响不大，对缺陷定位和定量的影响可以忽略。因此，综合分析认为，用合适的声速和衰减系数指标来判定对比试块与被检工件声学性能的近似性比较合理。

Comparison was made of provisions of the acoustic properties of reference blocks in the domestic and foreign ultrasonic testing standard through the comparative analysis. It is appropriate to use sound velocity and ultrasonic attenuation to represent acoustic properties of material. The methods for the determination of sound velocity and attenuation coefficient of reference block and the test object were introduced, and sound velocity and attenuation coefficient of steel plate in parallel with and perpendicular to the rolling direction, respectively, were tested. According to the test results, the anisotropy of steel plate had little influence on velocity and attenuation coefficient α, and its influence on the defect location and quantification could also be ignored. Therefore, the comprehensive analysis showed that it was more reasonable to use sound velocity and attenuation coefficient as the appropriate index to determine the acoustic similarity of the reference block and test object.