Dielectric testing is essential in developing ceramic insulators for spark plugs used in modern engine platforms. Many test methods are developed for different materials and applications. At Autolite, parallel plate dielectric testing based on the ASTM standard was used for material evaluation. The paper will cover the factors that influence the measurements in these tests as well as a comparison of insulator materials from different spark plug manufacturers. Furthermore, to better evaluate the performance of final product, Autolite developed a proprietary engine dielectric test method for spark plugs. The test method is compared with most conventional tests in the automotive industry, and the performance of spark plugs using Autolite conventional and next gen ceramic will be reported.
