Silver Tungsten vs Silver Tungsten Carbide Contact Performance in Environmental Testing

The conductive performance of contact pairs varies greatly in testing due to their materials and to the probabilistic nature of how two parts can interface together. Contact pairs with different combinations of silver tungsten and silver tungsten carbide were exposed to salt spray test ASTM B117 for one week and two week intervals. Their resistance was then measured and analyzed using automated acquisition equipment and statistical methods. A simple probabilistic parallel resistor model was also created to simulate the range of results seen. The results are useful to other engineers working in this field to show the importance of taking multiple readings and using replicates in testing to account for normal variation. The model is helpful in visualizing what is perhaps happening in the contact interface.