A turbocharger rotor shaft assembly and associated turbocharger that includes at least one turbine rotor member having a first face and an opposed second face; and a rotor shaft having a first end and an opposed second end distal from the first end, wherein the rotor shaft is connected to the at least one turbine rotor at a location proximate to the first end and projects outward therefrom, the rotor shaft having an outwardly oriented face and an interior chamber defined therein, the interior chamber having an interior chamber volume. The turbocharger rotor shaft also includes at least one thermal transfer material contained in the interior chamber of the rotor shaft that has a thermal conductivity value that is greater than the thermal conductivity value of the material of construction of the rotor shaft.