Development and Production of a Lead-free Electronic Turbocharger Board

Due to legislative, market, and technical pressures there is a move towards lead-free solder usage in the automotive electronics manufacturing industry.

This paper will discuss the development work of a lead-free turbocharger product board that was used to enable the product to be used in a long-term operation within harsh, higher temperature environments. It was found that the lead-free product was more reliable than the lead-containing version.

Process parameters used for lead-free assembly were compared with tin-lead production. Tests were conducted on assembled component boards with various lead-free SnAgCu (Tin-Silver-Copper) solder pastes and thick film Ag-based conductors comparing them with tin-lead solder and thick film Ag-based conductor. Data collected after aging of the components by thermal shock (-40/+150°C and - 40/+175°C), high temperature storage (150°C and 175°C), and mechanical testing was reviewed. Based on the results, the specific SnAgCu and AgPtPd (Silver-Platinum-Palladium) combination of materials were recommended for use in production.