|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1993 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1992 : ¥1,500,000 (Direct Cost : ¥1,500,000)
Strength characteristics and frature mechanim of a silicon carbide matrix reinforced by continuous silicon carbide fiber were investigated. In the material, satin woven cloths with carbon-coated fiber were impregnated in matrix binder, followed by repeated process of molding, cure and burning. Specimens subjected to loading vertically to stacking layrs and those pallarel to stacking layrs were designated as V-specimen and P-specimen, respectively. Unstable fracture was not observed for both types of specimen, because of interface property refined by carbon coating on fiber. Apparent fracture toughness and bending strength in P-specimen were found to be larger than those in V-specimen. This was resulted from difference in the fracture morphology depending on stacking direction. In V-specimen, pull-out and tensile rapture of fibers were dominant in fracture process, and resulted in separation into two parts. On the other hand, in P-specimen, separation in interlaminate was obserbed before final frature. The differnce in macroscopic fracture pattern was supposed to appear in the fracture resistance. The reinforcement effect by fiber in the present material was investigated by ccmlparison with strength characteristics of the matrix material. In this case, the strength characteristics of the matrix material were estimated by taking account of its bulk density. By the comparison, apparent fracture toughness and bending strength of each type of specimen were found to be larger than those estimated for the matrix. The effect of fiber reinforcement was concluded to be affirmed as long as strength of the bulk material was compared with that of matrix strength.