A funding proposal to investigate lead free solder for electronics has been submitted to the UK government's Engineering and Physical Sciences Research Council (EPSRC) by the UK Network for Waste Reduction in Aircraft Related Groups (WINGNet).
Aerospace companies expect lead-based solders to be outlawed for aircraft in the future and want to ensure there are lead-free alternatives. Lead solders are illegal in many other industries already. WINGNet expects a decision from EPSRC soon and research to begin in late May or June.
"Even if we don't get EPSRC funding we will go ahead because there is so much support for this from industry," says Patrick Grant, University of Oxford department of materials' professor of material processing. The research will involve highly accelerated life testing and long-term temperature soaks of lead free materials.
The candidate materials are tin copper, tin silver, tin silver copper, tin silver bismuth and tin zinc. Outside aerospace the most commonly used lead free compound is tin bismuth, but this has a melting point that is too low for aerospace's needs. After testing, the lead-free solders' microstructures will be examined to find cracks and voids that could hinder performance.
Source: Flight International
