Impeller for aircraft engine

An aircraft engine comprising:

• a compressor having an impeller rotatable about a central axis, the impeller having an inlet and an outlet downstream of the inlet, the impeller having a gaspath face extending from the inlet to the outlet, the impeller having:
• a front face and a rear face axially rearward of the front face, the rear face extending radially outwardly relative to a central axis from a bore of the impeller, the impeller having an inlet and an outlet downstream of the inlet, the impeller having a gaspath face extending from the inlet to the outlet;
• an outer hub body including a first material and extending around the central axis, the outer hub body defining an entirety of the gaspath face, an entirety of the rear face defined by the outer hub body;
• blades protruding from the gaspath face and circumferentially distributed around the central axis;
• and
• an inner hub body extending around the central axis, the inner hub body secured to the outer hub body, the inner hub body contained within a recess defined by the outer hub body, the inner hub body made of a second material being more cold dwell resistant than the first material, the inner hub body having an outer face facing an inner face of the outer hub body, an annular gap between the outer face and the inner face, the inner hub body located entirely radially inwardly of the gaspath face.