2002 Volume 66 Issue 6 Pages 662-669
A turbine disk model, which uses a C/C composite material to lighten the turbo machinery rotor for a trial HTGR-GT system, was fabricated to try to achieve a circumferential speed of up to 500 m/s during the spin test. In the present study, the design and production of the largest turbine disk model (the outside diameter×inside diameter×thickness=φ450 mm×φ250 mm×t40 mm) in the world has been implemented by high strength carbon fiber reinforcement in the hoop, radius and thickness directions and SiC/I-CVI processing. As a result of the spin tests, the following conclusions were obtained.
(1) SiC layer of 2.5-20 μm in thickness was achieved by SiC/I-VCI processing in the C/C composite disk model with 40 vol%, 10 vol% and 4 vol% carbon fiber in the hoop, radial and thickness directions.
(2) SiC layer formation in the disk model structure shows reinforcement and prevention against delamination of carbon fiber in the disk model at spin test.
(3) 500 m/s circumferential speed was achieved by spin test of SiC/I-CVI C/C composite disk model. This value is the fastest speed recorded by two or three dimensional reinforcement C/C composites.
(4) Fracture of the disk model was induced by crack initiation and propagation from inside to outside wall surface of the disk model, observed by a direct crack propagation observation technique.
