Patent ID: 8205668

Claim:
An exhaust gas recirculation cooler comprising: a housing including an exhaust gas region, a coolant region, an exhaust gas inlet that provides communication between an exhaust gas from an engine and the exhaust gas region, an exhaust gas outlet that provides communication between the exhaust gas region and an engine intake air supply, and a coolant inlet and a coolant outlet in communication with the coolant region and hydraulically isolated from the exhaust gas inlet and the exhaust gas outlet; and a first wall fixed within the housing and separating the exhaust gas region from the coolant region, the first wall including a first portion formed from a first material and facing the exhaust gas region and a second portion formed from a second material and facing the coolant region, one of the first and second materials having a coefficient of thermal expansion that is greater than the other of the first and second materials, the first wall being deflected toward one of the exhaust gas region and the coolant region during cooler operation based on a difference in the coefficient of thermal expansion of the first and second materials.