Metal plated additively manufactured plastic ACM rotors with internal thermally adaptive structure

A method of forming a rotor for an air cycle machine (ACM), the method comprising:

• forming a rotor base having a plurality of discrete sections including:
• a first section that is adjacent to a diffuser shroud when installed in the ACM;
• a second section that forms a seal and is disposed against an aft frame member when installed in the ACM;
• a third section that is connected to a compressor rotor shaft when installed in the ACM;
• a fourth section that is connected to a tie rod when installed in the ACM;
• a fifth section that is between the second section and the fourth section,
• wherein forming the rotor base includes:
• printing, layer by layer, the rotor base, by printing first and second thermoplastic polymer surfaces, respectively from first and second thermoplastic polymers, that are disposed against each other, the first thermoplastic polymer surface having a first coefficient of thermal expansion (CTE), and the second thermoplastic polymer surface having a second CTE;
• forming a lower support section on the rotor base by printing, layer by layer, along the plurality of discrete sections of the rotor base a mixture of a third thermoplastic polymer and a catalyst formed with metal;
• and
• forming an upper support section on the rotor by depositing on the lower support section, along each of the discrete sections, via electrolysis deposition, a metallic coating, to thereby control thermal expansion and contraction of the rotor along the discrete sections, to thereby make the rotor,
• wherein forming the rotor base includes printing, layer by layer, a lattice of beads, wherein each of the beads has an outer surface formed by the first thermoplastic polymer surface and an inner surface formed by the second thermoplastic polymer surface, and wherein a void is formed in a center of each of the beads.