Lead free solder alloys Sn-Zn and Sn-Sb prepared by mechanical alloying

The mechanical alloying (MA) processes of tin-9zinc (Sn-9Zn) and tin-5antimony (Sn-5Sb) were analyzed using an X-ray diffractometer, a differential scanning calorimeter (DSC) and a scanning electron microscope (SEM). The results showed that supersaturated solid solution and intermetallic compound were produced during the MA process. The size of powder particles could be controlled under the proper MA conditions and was reduced to 5 to 20 mu m. As a surfactant, proper addition of rosin allows MA to occur smoothly. However, it may also be a source of contamination of the metallic powder. It is considered that MA may be a technique analogous to casting to prepare solder alloys.