A damper assembly includes a housing that defines an interior chamber. A rod is supported by the housing, and is at least partially disposed within the interior chamber. A piston assembly is attached to the rod within the interior chamber. The piston assembly separates the interior chamber into at least a first fluid chamber and a second fluid chamber. The piston assembly includes an annular plate defining at least one orifice, which interconnects the first fluid chamber and the second fluid chamber in fluid communication. The piston assembly includes at least one valve disc that is disposed adjacent a first face of the annular plate. An SMA device is disposed in contact with the valve disc. The SMA device is changeable between a first state and a second state, at a transition temperature, to control a bending stiffness of the valve disc to adjust a damping rate.