A turbine disk model has been trially fabricated and tested which uses C/C composite material to lighten the turbo machinery rotor for HTGR GT system. In present study, the design and production of the most large scale 1/5 reduction turbine disk model (the outside diameter×inside diameter×thickness＝q400 mm×q300 mm×t30 mm) in the world which enforced three dimensional structure to the hoop, radius and thickness directions using the high strength carbon fiber has been implemented. As a result of spin tests, following conclusions were obtained.(1) To establish an enforced structure to endure the amount of hoop tensile stress which occurs in spin test in case of design of the 1/5 disk model, 40 vol carbon fiber containing quantity to the hoop direction in the preform was chosen. Moreover, to endured a compressive force to the thickness direction and prevent the delamination in the aspect of the carbon fiber product layer during spin test, the carbon fibers of 10 vol and 4 vol has been added to the thickness and radial directions.Moreover, this preform was experimentally fabricated using the large scaled carbon fiber weave equipment (the maximum manufacturing possible shape, the diameter×thickness, 1.5 m of q2 m) and the experimental production of the 1/5 disk model was successfully implemented which is made from the C/C composite which was strengthened in the three dimensions, then graphitized and densified.It is possible to manufacture the full size gas turbine disk of the HTGR GT system by the application of this manufacturing technology.(2) The ordinary circumferantial speed (～350 m/s) of the small disk experimental production body has been achieved which is made form two or three dimensional reinforcement C/C composite in the past in case of spin test of the 1/5 reduction disk model.(3) Moreover, in case of the solid disk created in the identical manufacturing condition, it was considered that the specimen can achieve the high rotational speed performance condition of the HTGR GT system.
