Lead-free Wave Solder Alloy Selection: Reliability Is Key

摘要

The eu's rohs directive is driving major chances in the manufacture of electrical and electronics equipment. the most significant change is the elimination of lead from solder joints. this article details the process that one consumer electronics company used to make their lead-free alloy selection. For much of the time wave soldering has been used in the mass production of solder joints on PCBs, there has been one mainstream alloy - tin/lead eutectic Sn63/Pb37. With the requirement to install lead-free wave solder processes, companies have a choice of alloys. One consumer electronics company used a four-stage selection process to make this decision. This process included: 1. Determining the criteria that needs to be considered when making the selection: process yield DPMO, process maintenance, component and board compatibility, in-service reliability and total cost of ownership. 2. Initial screening of available alloys and the generation of a short list. 3. Processyieldexperimentation-Design of Experiment (DoE) setup, optimized process settings. 4. Reliability testing - Final stage of the alloy selection process, involving thermal cycle and extensive joint examination.