中厚板超声波探伤合格率提高攻关实践.pdfVIP

46 3 Vol. 46, No. 3 2 0 1 1 3 Iron and Steel March 2011 1 1 1 2 1 1 许少普 , 崔冠军 , 刘庆波 , 吴 彦 , 袁少威 , 张智慧 ( 1. , 474500; 2. , 474500) : , , , , , : , , 50. 4% 92.3% : ; ; : : 0449749X(2011) Practice of Improving the Qualified Ratio for Ultrasonic Flaw Detection of Plate 1 1 1 2 XU Shaopu , CUI Guanjun , LIU Qingbo , WU Yan , 1 1 YU N Shaowei , ZH NG Zhihui ( 1. Iron and Steel Research Institute of Nanyang Hanye Special Iron and Steel Co. , Ltd. , Nanyang 474500, Henan, China; 2. Patent Office of Nanyang City, Nanyang 474500, Henan, China) Abstract: In order to find out the reasons for nonconformity in ultrosonic flaw detection of medium plates, the distri bution law of the qualified ratio of flaw inspection was found by statistical analysis. The samples of typical steel grades were cut from defective parts, the structure and composition of which were analyzed by metallograph, scan ning electron microscope (SEM) and energy spectrum. T he results show that there are the banding manganese sul phides, the segregation of manganese and microcrack is caused by abnormal structure of granular bainite. ccording to the above reasons, a series of control measures were adopted, the qualified ratio of flaw inspection was increased from 50. 4% ( prior to research) to 92.3%. Key words: medium plate; ultrasonic inspection; practice , , (, ) 2008 , ,