闪光对焊焊接380CL钢轮辋焊缝开裂原因分析

Weld Cracking Analysis of 380CL Steel Rim Welded by Flash Butt Welding

摘要: 利用光学显微镜、扫描电子显微镜等分析了闪光对焊焊接380CL钢轮辋焊缝开裂的原因。结果表明: 该轮辋焊缝的开裂为脆性开裂, 焊缝区晶粒异常长大及焊后冷速较快而产生的粗大魏氏组织是其失效的根本原因; 通过优化闪光对焊工艺, 降低焊接时焊缝中心高温停留时间以有效控制焊缝奥氏体晶粒尺寸, 可以保证焊缝良好的强韧性、避免焊缝开裂。

Abstract: The weld cracking reason of 380CL steel rim welded by flash butt welding was analyzed by using optical microscope, scanning electron microscope and so on. The results show that the weld cracking of the rim was brittle cracking. The coarse widmansttten structure, which was produced due to the abnormal growth of grains in weld seam and the rapid cooling rate after welding, was the main reason for the cracking failure. By optimizing the flash butt welding process, shortening high-temperature residence time in the weld center to effectively control the weld austenite grain size and ensuring a good strength and toughness property of the weld would prevent the weld cracking.