A microturbine system includes a compressor, a recuperator assembly, a combustor, a turbine, and a generator. The recuperator assembly includes a core that preheats compressed air provided by the compressor with exhaust gas from the turbine. The preheated compressed air is mixed with a fuel and burned in the combustor. The products of combustion are used to drive the turbine, which in turn drives the compressor and generator. The recuperator core is surrounded by a recuperator housing that is intimate with the recuperator core such that the recuperator housing assumes substantially the same temperature as the recuperator core. The recuperator housing is constructed of materials that have a coefficient of thermal expansion that is substantially equal to that of the recuperator core, and that have thicknesses substantially equal to the thickness of the recuperator core materials. A superstructure supports the recuperator core and resists expansion of the core in a stackwise direction. The superstructure includes tie rods outside of the recuperator housing, and the tie rods are substantially thermally isolated from the heat of the recuperator assembly by insulation.