The challenge of lead-free electronics for aerospace electronic systems

Driven by legislation resulting from two European Union directives, most commercial electronics manufacturers began delivering lead-free electronic components, assemblies, and equipment in 2006. Although not generally affected directly by the legislation, the aerospace industry is being swept along as its electronics supply chain makes the transition which significantly impacts the design, production, and support of aerospace electronic systems. Because of its unique requirements such as long service lifetimes, reparability at the assembly level, rugged operating environments, and high consequences of failure, the aerospace industry must develop its own response to the challenges posed by lead-free electronics. This paper addresses some of these challenges: (1) structures and properties of the most common lead-free alloys; (2) testing and evaluation of lead-free alloys, (3) tin whiskers, and (4) some of the specific aerospace program concerns such as reliability, repair, and product support.