Date of Graduation


Document Type


Degree Name

Bachelor of Science in Mechanical Engineering

Degree Level



Mechanical Engineering


Zou, Min


Piston rings are designed to provide a seal between the piston and the cylinder wall of internal combustion engines, keeping oil from the crankcase from getting into the combustion chamber. This means piston rings are the main point of contact between the piston and the cylinder wall, which causes the piston to experience high amounts of friction and wear. By texturing the surfaces of the cylinder wall and/or the piston ring, the amount of contact area can be reduced, allowing for less friction, slower wear, and better gas mileage. In this thesis experiments, photochemical etching processes were developed to etch nitrided stainless steel piston rings with designed geometrical patterns for the purpose of friction reduction. Studies were performed to investigate several types of photoresists, optimize the printing parameters for the photoresist AZ-9260, and to determine the etching rates of hydrochloric acid. The results showed that it is possible to accurately etch distinct shapes at the micro scale while controlling the etching depth. This research demonstrates the feasibility of texturing the flat side of piston rings through photochemical etching for the purpose friction reduction, and the research results provide a solid basis for future studies to further refine and apply the same techniques to selectively etch the curved surface of the piston ring.


Photochemical Etching, Nitrided Stainless Steel Piston Rings, AZ-9260, Etch Rate, Service learning