日本日立制作所与日立研究所试验成功一种新的超声波探伤法,命名为“广角探伤法”。此法可以明显地检查出距钢材表面5cm深处的1mm间隔的微细伤痕,从而把原来的超声波探伤技术提高到一个广角高效的新境界。对钢材表层深处进行非破坏探伤,一般都采用“X”线、γ-Gamma射线和超声波。至于超声波探伤,尽管有各种各样的发射和接收方式,但为了提高其正确性,一般都把超声波的波束尽可能地聚焦,用扫描的方法对钢材进行检查。但是,由于声束的集中,被检面积仅局限于狭小范围,检查效果受到限制;如要扩大探伤范围,势必将声源的距离拉 Japan’s Hitachi and Hitachi Institute successfully tested a new ultrasonic flaw detection method, named “wide-angle detection method.” This method can obviously detect the fine scratches 1mm apart from the steel surface 5cm deep, so that the original ultrasonic flaw detection technique is raised to a new angle of wide-angle and high efficiency. Non-destructive testing of the depths of steel surfaces generally uses “X” lines, gamma-gamma rays and ultrasound. As for the ultrasonic flaw detection, in spite of a variety of transmitting and receiving methods, in order to improve its accuracy, the ultrasonic beam is generally focused as much as possible, and the scanning method is used to inspect the steel. However, due to the concentration of acoustic beams, the area under test is confined to a narrow area and the inspection effect is limited. To expand the testing area, the distance between sound sources