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Failure Analysis of Internal Combustion Engine Valves: A Review

Naresh Kr. Raghuwanshi, Ajay Pandey, R. K. Mandloi

Intake and exhaust valves are very important engine components that are used to control the flow and exchange of gases in internal combustion engines. They are used to seal the working space inside the cylinder against the manifolds; and are opened and closed by means of what is known as the valve train mechanism. Such valves are loaded by spring forces and subjected to thermal loading due to high temperature and pressure inside the cylinder. The present study focuses on different failure modes of internal combustion engine valves, failures due to fatigue at high temperature, high temperature effects on mechanical properties of materials, like hardness and yield strength; wear failure which is due to impact loading, and wear rate that depends on load and time. For the study of fatigue life, a combined S-N (max. stress v/s number of cycles) curve is prepared. Such a curve helps in comparing the fatigue failure for different materials at different high temperatures and may also assist the researchers in developing the valve materials with a prolonged life.