アルミニウムのマイクロソルダリングへの適用性に及ぼす合金元素の影響

抄録

The wettability and applicability of the aluminum alloys for micro-soldering have been investigated using a wetting balance tester by using Sn-9Zn solder and triethanolamine-ammonium fluoroborate flux. Wettability was evaluated by wetting time, wetting force and contact angle between aluminum specimen and solder. Commercial alloys containning lots of impurity elements showed poor wettability whereas the alloys with small amount of elements possessed good wettability with short wetting time, large wetting force and small contact angle. The influence of each elements on wettability was estimated from the data on commercial alloys, and was investigated by using high purity binary alloys. Elements of Ti and Cu drastically lowered the wettability, Cr, Mn and Mg also lowered wettability. Especially, the alloys for microsoldering should have Ti less than 0.04 mass%. The cause of poor wettability depends on the additional elements, both the formation of stable intermetallic compounds and solution of elements were responsible to poor wettability. Pure aluminum, A1080 and some high purity binary alloys were considered to be suitable for micro-soldering under consideration of wetting time and contact angle.