LEAD-FREE SOLDERING METHOD AND SOLDERED ARTICLE

摘要

Prevention of the occurrence of voids and solder wettability are improved in a method for soldering an Ag-containing lead-freed solder to be soldered to an Ag-containing member. A method for soldering an Ag-containing lead-freed solder according to the present invention comprises: a first step wherein an Ag-containing member and a lead-free solder, which has a composition containing Ag such that the relationship between the Ag concentration C (mass %) contained in a mass M (g) of an Sn-Ag based lead-free solder before soldering and the elution amount B (g) of the Ag contained in the Ag-containing member satisfies 1.0 mass % ≤ (M × C + B) × 100/(M + B) ≤ 4.6 mass %, with the balance made up of Sn and unavoidable impurities, are brought into contact with each other; a second step wherein the lead-free solder is heated and melted; and a third step wherein the lead-free solder is cooled.