U75V钢轨轨腰探伤不合原因的分析

Analysis of the Failed Detection on U75V Rail Waists

为查明U75V钢轨轨腰探伤不合原因,采用垂直探伤定位法准确定位缺陷后,利用光学显微镜、扫描电镜对定位的缺陷部位进行了非金属夹杂物、金相组织等检验分析。结果表明,在U75V钢轨轨腰探伤不合处存在长度超过2.0 mm的异常大硅酸盐类非金属夹杂物和组织偏析,分析认为异常大硅酸盐类非金属夹杂物是导致探伤不合的主要原因。

To find out the reason of the failed detection on U75V rail waists,after the defects was located by double vertical detection,non-metallic inclusions and metallurgical structure were investigated with the optical microscope and SEM.The results show that there are silicate inclusions with its size longer than 2 mm and micro segregation in the detect location,and it is believed that the exceptional silicate non-metallic inclusion is the main reason for failed detection.