User talk:Yoka2013

�Advantages of environmental seamless copper-aluminum brazing solder�

�Saving materials: The copper-aluminum solder with gap, being opened easily in bend process, causing flux leakage and brazing solder wasting. While seamless copper-aluminum solder, as without gap, and avoid this negative phenomenon thoroughly.� �Improving welding quality: It is easy of packed flux absorbing humidity and cause unstable welding quality and air hole for the gap existing in the copper-aluminum solder with seam; hence, oversea company take seamless technology; with stable quality and lower rate of air hole for seamless, and not easy to absorb humidity.�

�Automatic brazing solder, the leaking rate of air hole is lower than 0.01%, while the one with gap is too far to reach this requirement. �

Disadvantages of traditional aluminum brazing 1. The melt point of aluminum soldering materials is 580 degree or so, which is close to the parent materialss’ of 630 degree. With high defective rate of welding, it requires using experienced and skilled aluminum technician in real brazing production, caused high cost as well. 2. Choosing corrosive flux is easy to cause solder corroded once it entered inside of tube. 3. for the flux and solder are separately, there would be certain difficult to carry out automatic brazing. And directly restrict the implementation of the process of mass automation.

History of Environmental automatic brazing aluminum solder

1999 Germany Hannover Material Research Institute, developed the enviromental automatic brazing aluminum solder, mainly used in European aerospace industry.

2002 Japan, Osaka electronic materials research institute,developed enviromental automatic brazing aluminum solder, and mainly used in aerospace industry in Japan and American.

2009, China, the technical director,Zhaotao Duan, from Center of Jinggu material research center, took 5 years, finally, developed environmental automatic brazing aluminum solder; the successfully broke means China also walk in the forefront of advanced material technology field in the world.