焊管压扁开裂的原因分析

• 作 者: 张达富 吴安术 刘锦燕
• 机 构: 攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室,
• 出 处: 物理测试
• 发表日期: 2016年05期
• 关键词: 焊管 金属流线 压扁试验 SEM 中心偏析 金属流线上升角 硫化物夹杂 焊缝 冶金分析 微观断口

某厂家的焊管在压扁试验过程中开裂,为找出焊管开裂的原因,在实验室对未开裂焊管进行了压扁验证试验,观察了开裂管的宏观形貌。并采用微观断口观察、金相分析及金属流线上升角测定等测试分析手段进行综合分析。结果表明,焊管开裂的主要原因是由于焊管中存在的硫化物夹杂破坏了焊管金属的连续性,在焊接过程中,焊缝处于较大挤压力下,使得金属流线上升角过大且露头,从而引起开裂,裂纹沿着管材的中心偏析位置向内扩展。

In order to find out the cause of cracking of welded pipe, the welded pipe of one manufacturer was cracked during the flattening test. The uncracked welded pipe was subjected to the flattening verification test in the laboratory, and the macroscopic appearance of the cracked pipe was observed. And the microscopic fracture observation, metallographic analysis and determination of metal flow line angle were used to conduct a comprehensive analysis. The results show that the main reason for the cracking of welded pipe is that the sulfide inclusions existing in the welded pipe destroy the continuity of the welded pipe. During the welding process, the welded joint is under a relatively large pressing force, , Causing cracking, which propagates inwardly along the central segregation of the pipe.