טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentRonen Aviram
SubjectImproving Tribological Properties of Automotive Mechanical
Components by Laser Surface Treatment
DepartmentDepartment of Mechanical Engineering
Supervisors Professor Emeritus Izhak Etsion
Dr. Yuri Kligerman


Abstract

About 40 percent of the total energy developed by a typical automotive engine is consumed by engine friction. Reducing this friction loss is a key factor in improving fuel consumption and environment protection. Of all the various engine components that contribute to the friction losses the piston and piston ring system accounts for about 50 -60 percent. It is not surprising therefore that engine friction in general and the friction of the piston/cylinder system in particular was the focous of many research works.

Proper lubrication and surface roughness are key issues in reducing friction in the piston/cylinder system and, hence, received great deal of attention in the relevant literature.

The main goal of this research is to study the potential use of regular surface texture in the form of micro-pores to improve tribological properties of reciprocating automotive components.

A new technology of laser treatment, which was developed by SurTech Ltd., enables to form a regular micro-surface texture of given parameters in order to reduce friction and wear and to enlarge life time of machine elements. The effect of such texturing on the friction force and fluid film thickness between the piston rings and cylinder liner was investigated in the present work.

It is shown that surface texturing can efficiently be used to maintain hydrodynamic effects even with nominally parallel surfaces. It is also shown that optimum surface texturing may substantially reduce (more than 25%) the friction losses in reciprocating automotive components.