#5-A Low Cost, High Reliability Contact Finish for Automotive Applications from Materion Technical Materials
Abstract: The proliferation of sophisticated automotive electronic systems has created demand for reliable low cost components. Even though the automotive environment is hostile, reliability must be maintained for extended periods of time. Potential failure modes include:
- Sliding wear
- Fretting wear and fretting corrosion
- Stress relaxation
- Galvanic corrosion
- Catalysis of airborne organic compounds
- Migration of corrosion products over and diffusion of base metal to the contact surface
This Materion Technical Materials study examines contact material performance during and after experiments designed to simulate the automotive environment. Both material coupons and assembled terminals were evaluated.
Mechanical and Environmental Tests
Mechanical tests included sliding wear and fretting. Environmental tests included porosity testing, thermal aging, temperature cycling with humidity and Battelle flowing mixed gas exposure. Key attributes which were measured and reported include porosity level, coefficient of friction during sliding and low level resistance changes.
It was found that a thin, multi-layer clad inlay contact material consisting of 10 µ-inches of WE #1 over 20 µ-inches 60Pd40Ag demonstrated stable behavior in the components under test. Cost information is provided and indicated that the clad inlay contact finish offers low cost material system with high reliability.