Date of Award


Publication Type

Master Thesis

Degree Name



Mechanical, Automotive, and Materials Engineering

First Advisor

Xueyuan Nie

Second Advisor

Jimi Tjong


Applied sciences, Internal combustion engines, Lightweight, Plasma electrolytic oxidation, Thin films and coatings, Tribology, Wear resistance




With increasing fuel economy and emission restrictions being placed onto the automotive industry, there is always a need for innovation and research in striving to reduce energy loss and make internal combustion engines more efficient. An area of potential improvement is through the reduction of frictional parasitic losses in tribological systems. This study investigates the feasibility of use for low-friction Plasma Electrolytic Oxidation (PEO) coatings on cylinder bores in order to reduce the frictional coefficients along the piston ring and cylinder bore sliding surface. For PEO coatings, wear is a limiting factor and this study aims at understanding the main influencing factors for wear on PEO in cylinder bores. Through fired-engine dynamometer testing, it was determined that large piston-to-bore clearance distances, increased oil retention, and a small dispersed surface porosity morphology created a tribological environment which produced improved wear resistance of PEO coatings in cylinder bores.