以激光选区熔化（SLM）增材制造钛合金（Ti-6Al-4V）材料为对象，研究了不同方向的超声波声速和底波衰减行为，分析了超声检测方法对于SLM成形钛合金的检测能力；针对超声检测异常部位，进行了工业CT（计算机断层成像）检测补充验证，证明了超声检测的有效性。试验结果表明，超声检测可检出SLM成形材料中的层状未熔合缺陷，可为SLM成形材料的检测提供参考。

In this paper, with the titanium alloy (Ti-6Al-4V) materials manufactured by selective laser melting (SLM) as research topic, the behaviors of ultrasonic sound velocity and bottom wave attenuation in different forming directions were studied; the capability of ultrasonic testing for SLM titanium alloy was analyzed; the abnormal parts of ultrasonic testing were selected for industrial CT supplementary verification to prove the effectiveness of ultrasonic testing. The test results show that ultrasonic testing can detect laminar unfused defects in SLM materials, which can provide a reference for the testing of SLM materials.