摘要
针对磷脱氧铜管与低碳钢储罐钎焊后漏气失效问题,采用金相、扫描电镜(SEM)和能谱分析(EDAX)对失效器件进行分析,发现铜管漏气的主要原因是由于钎焊过程中,预热和钎焊工艺不恰当,导致焊接气氛交替出现氧化性和还原性,使得铜管发生氢脆,产生裂纹。同时在加热和冷却时,由于异种材料的热胀系数差别过大,产生的较大热应力作用于已存在的裂纹,促使裂纹二次扩展,甚至使得晶粒脱落产生空洞,最终导致焊接接头漏气失效。提出了合理控制燃气比、钎焊加热时间和焊后冷却时间,以改善钎焊质量的建议。
The gas leakage failure of braze welding between the phosphorus deoxidized copper tube and stock tank of low carbon steel was investigated by means of metallography, SEM and EDAX analysis. Results show that the brittle fracture is mainly caused by hydrogen brittleness that results from the oxidation and absorbing hydrogen of copper tube during braze welding. Methods of brazing quality improvement are suggested as well.
出处
《理化检验（物理分册）》
CAS
2006年第2期92-94,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
磷脱氧铜
钎焊
漏气
氢脆
Phosphorus deoxidized copper
Braze welding
Gas leakage
Hydrogen brittleness
