Monotectic Al/Cd alloys with homogeneously dispersed Cd-droplets stabilized by strontium aluminide precipitates

Al-rich Al–Sr alloys contain dispersed Al4Sr precipitates in the Al-matrix. When melted and emulsified together with a smaller volume of Cd, Cd-rich droplets are formed (being immiscible with the Al-rich liquid). The Al4Sr precipitates prefer the Al/Cd interface, stabilizing the Cd droplets in the Al-matrix. The contact angle of the Cd-rich liquid on Al4Sr intermetallic phase under the Al-rich liquid alloy is about 90°, being ideal for emulsion stabilization. In this way, Al/Cd monotectic alloys can be produced with homogeneously dispersed Cd particles. The key to the success of this process is the in-situ formation of strontium aluminide precipitates stabilizing the Cd droplets in the liquid Al/Cd emulsion.