Sn/Ag0.3/Cu0.7???????????S???????????????c?????????O????????a???~??????u???ɡ??к???B?m????????????????u?????????????????t??и????????x?????u?????????y?????????????ě????????????????ИO?????????ò????????????~???????????яV????á?

1. ??????
1.) ?B?m???r??????O????r???????@?÷???????????
2.) ??0.4 mm?????g????·????????????????
3.) ???ИO????????????????λ??F???m??????????
4.) ???m???????????c?????????t??
5.) ?O??????????￡?????@?????????????