Lead‐free solders in Japan (a personal impression)

Abstract

Impressions gained from two visits to Japan, discussing with representatives of industry and academe the current status regarding the implementation of lead‐free technology, are presented. Driven by the commercial rewards of lead‐free goods, Japan appears to have more clearly articulated targets for the removal of lead, in advance of the expected timescales in EU legislation. Various strategies for combating problems associated with the higher melting point of lead‐free solder alloys have been investigated. Design and development generally involve a broader approach than in Europe, involving stress analysis, materials properties and life prediction to underpin empirical data obtained by thermal cycling of boards. Despite the existence of several committees to facilitate the introduction of lead‐free solders, a lack of cohesion is sometimes apparent, particularly regarding heat treatment of materials prior to testing. It is proposed that a challenge as demanding as this would benefit from greater collaboration internationally.