Reliability methods for structural composite applications in vehicle suspensions

Delphi Chassis efforts in the area of advanced composites have focused on developing highly reliable suspension modules and components at a low cost and reduced mass. Delphi Chassis has developed two processes for use in automotive suspension applications. The first is a fiberglass filament winding process used to manufacture Liteflex™ composite leaf springs. A more recent process, used to manufacture Litecast™ suspension links, consists of die casting a metal (aluminum) end fitting directly onto a pultruded polymeric composite rod (fiberglass, graphite). High reliability and confidence targets are met through lab and field validation testing that duplicates customer usage. Accelerated lab testing is utilized to reduce test times and cost by identifying what types of inputs are damaging to specific component. An accelerated, multi-environment, overstressed forced failure approach is utilized to predict reliability based on customer usage. Delphi is utilizing this forced failure reliability test approach to thoroughly understand and optimize their components before reaching the customers hands.