ALLIED-SIGNAL CORP TORRANCE CA GARRETT AUTOMOTIVE GROUP
Ceramic turbine rotors for turbochargers, because of the materials low density, offer faster turbocharger rotor acceleration which improves engine response and vehicle acceleration. Ceramics use relatively low cost materials in place of the currently used expensive, exotic and sometimes scarce metal elements and, hopefully, will allow the production of less expensive rotors. Only in the past few years have prototype ceramic rotors been produced. The U.S. Army Tank-Automotive Command TACOM established a program to demonstrate the feasibility of producing a cost effective ceramic rotor for military use with Garrett Automotive as the prime contractor and the AiResearch Casting Company ACC as the major sub-contractor. While ACC has been able to produce small passenger car ceramic rotors, within the timeframe of this program, ACC was not able to produce a satisfactory large turbocharger rotor. A major goal of this program was to develop a domestic source for rotor production, but from Garretts experience no other U.S. company was capable. Therefore, to conclude the program with demonstration hardware, a Japanese supplier of known capability Kyocera was asked to make the rotors. Keywords Ceramic rotor, Turbocharger, Shaftwheel assembly, Silicon nitride, Slip casting, Ceramic rotor Design, Ceramic rotor fabrication, Ceramic rotor turbocharge testing.