Erosion in multiphase systems

Abstract Erosion behavior was analyzed for the case where the erosion impact events are small relative to the microstructural scale in multiphase systems. A mechanism-independent inverse rule of mixtures averaging law was derived for this situation. The linear rule of mixtures does not apply in this case. Erosion measurements on multiphase Al-Si alloys for a range of erodent particle sizes confirmed the validity of the inverse law. When the erosion impact events are comparable in size or larger than the scale of the microstructure, the inverse law should no longer be applicable, and the measurements showed systematic deviations that confirm this expectation. Certain complications and possible exceptions to the general inverse law are also discussed.