Date of Award


Publication Type

Master Thesis

Degree Name



Mechanical, Automotive, and Materials Engineering

First Advisor

Edrisy, Afsaneh (Department of Mechanical, Automotive and Materials Engineering)


Engineering, Materials Science.




The wear mechanisms of novel linerless eutectic Al-Si engines subjected to extensive dynamometer testing have been thoroughly investigated using an array of surface and subsurface techniques to elucidate the effects of alloying, surface preparation, and temperature on the overall wear progression of linerless Al-Si engines. The efforts of this research have revealed that the long term wear resistance of linerless eutectic Al-Si engine bores is derived from the combined effects of oil deposits, silicon exposure, and the formation of reduced grain structures in the aluminum-matrix. Under this criterion, silicon particles maintained exposure at an equilibrium height of ~0.4 to 0.6 um. Amorphous structured oil deposits, abundant on the worn surface, were shown to fill/protect uneven areas on the aluminum-matrix. The evolution of the bore microstructure is explained in terms of fragmentation of silicon particles and subsequent "polishing" of the entire worn surface caused by sliding contact with the rings.