Piston ring assembly including a self accommodating smart piston ring

摘要

A piston ring assembly includes a piston ring formed of a shape memory alloy. By using a shape memory alloy material, the piston ring changes its shape during exposure to transient thermal conditions so as to minimize engine wear. The shape memory alloy composition of the piston ring is selected to exhibit a martensite phase during cold start operating conditions and as the temperature increases changes to the austenite phase so as to recover its original shape.