Development of bench test methods for the evaluation of ion-implanted materials: Piston/bore application

We report the progress made in developing novel bench test methods that will eventually facilitate the evaluation of materials modified by ion implantation or surface coatings. The friction related to engine piston and bore materials under limited lubrication conditions is used as a starting point for the overall investigation. Two types of tribometers, pin-on-disk and Cameron-Plint machines, have been used and shown to be suitable and complementary to each other. With this approach, we have studied the scuffing-related friction behavior of aluminum 390 alloy and cast iron used in the engine cylinders. We show that under suitable lubrication and load conditions these tribometers not only offer means of understanding material interactions which will assist in the selection of better implants, but also provide a quick screening method necessary for the development of new surface modification techniques.