If the elastic properties of a composite are isotropic, sheets were stacked in the same orientation. In the pre- the FEM analysis result for the monolithic part is liminary calculation, the anisotropy was ignored. The applicable to a composite part. The composite of this thickness of the center section of the composite par study has anisotropic elasticity because the plain-weave and the monolithic part were different, 4 and 3 mm, 270° 90°H3 8 H4 strain gauges Fig. 6. Internal hydraulic pressure test of the inner scroll support. Apparatus (a) and gauge positions to measure strains(b);(c)is an enlarged 0.0020 0.0015 苏0.0010 0.0005 270° Fig. 7. Final product. Fig. 9. Hoop strain distribution measured on the composite part Oil pressure 10 MPa 200 150 切 Maximum stress 270 MPa pture test 000010.002000300040.005 ydraulic pressure test. The stress was calculated by FEM analysis of a monolithic silicon Fig. 10. Stress/strain curves from a hydraulic internal pressurizationIf the elastic properties of a composite are isotropic, the FEM analysis result for the monolithic part is applicable to a composite part. The composite of this study has anisotropic elasticity because the plain-weave sheets were stacked in the same orientation. In the pre￾liminary calculation, the anisotropy was ignored. The thickness of the center section of the composite part and the monolithic part were di€erent, 4 and 3 mm, Fig. 8. Stress distribution generated by internal hydraulic pressure test. The stress was calculated by FEM analysis of a monolithic silicon nitride part. Fig. 7. Final product. Fig. 6. Internal hydraulic pressure test of the inner scroll support. Apparatus (a) and gauge positions to measure strains (b); (c) is an enlarged illustration of the section C in (b). Fig. 9. Hoop strain distribution measured on the composite part (loading pressure was 4.86 MPa). Fig. 10. Stress/strain curves from a hydraulic internal pressurization test. K. Sato et al. / Composites Science and Technology 59 (1999) 853±859 857