轨道交通铸钢制动盘缺陷AUT技术及试验研究

Automatic Ultrasonic Testing Technique and Experimental Study on Defects of Cast Steel Brake Disc in Rail Transit

针对铸钢制动盘近表面、近底面缺陷检测效果差的问题,设计了参考试块,开展了检测参数研究,对比分析后确定了适宜的频率、晶片直径和能量会聚深度。研制了自动超声检测装备,设计了扫查路径和扫查参数,可以实现铸钢制动盘两个盘面的快速检测。通过对参考试块、验证试样及实物的检测试验发现,自动检测可以有效检出靠近表面2 mm的缺陷及靠近底面1 mm的缺陷。自动检测比手工检测的缺陷检出率更高、检测重复性更好、稳定性更高、检测效率大幅提升。

A reference test block was designed and the testing parameters were studied to solve the problem of poor detection effect for near surface and near bottom surface of cast steel brake disc. After comparative analysis,the appropriate frequency, element diameter and energy convergence depth were determined. The automatic ultrasonic testing(AUT) equipment was developed, and the scanning path and parameters were designed,which could test rapidly the two faces of the cast steel brake disc. Through the test of reference blocks,specimen and real objects, it is found that the automatic testing could effectively detect the defects 2 mm near the surface and 1 mm near the bottom surface. Automatic testing showed higher defect detection rate, better testing repeatability and higher stability than manual testing. Compared with the manual testing, the efficiency of the automatic testing was greatly improved.