摘要
针对Q690D钢焊接后出现裂纹的现象,采用化学分析仪、金相显微镜、扫描电子显微镜对钢板的化学成分、金相组织、断口形貌及夹杂物等进行了系统的观察与分析。结果表明:材料的化学成分、金相组织、夹杂物等均在产品质量标准之内,焊接后出现裂纹的主要原因是焊接工艺不规范而导致的材料延迟性脆性开裂。为此制订了合理的焊接工艺规程,通过加强预热、焊后缓冷、优化焊接工艺参数、多道次焊接、焊后消氢处理等措施,有效地避免了焊接裂纹的出现。
The cracks occurred for Q690 D steel after welding. In view of this phenomenon,the chemical composition,metallographic structure,fracture morphology and inclusions in steel plate were observed and analyzed systematically by means of chemical analyzer,metallographic microscope and scanning electron microscope. The results showed that the chemical composition,metallographic structure and inclusions of materials could all meet the quality standard of products. The delayed brittle fracture was mainly caused by the nonstandard welding procedures. Therefore,the reasonable welding procedures were developed. The welding cracks could be effectively avoided by the measures such as preheating enhancement,slow cooling after welding,optimizing the welding parameters,multi- pass welding and hydrogen-eliminating treatment after welding.
出处
《物理测试》
CAS
2016年第1期18-21,共4页
Physics Examination and Testing
