MAEKAWA Zenichiro Associate Professor, Fuculty of Textile Science Kyoto Institute of Technology, 繊維学部, 助教授 (60047149)
JINEN Eiichi Professor, Technical College, Kyoto Institute of Technology, 工業短期大学部, 教授 (60027878)
IWAMOTO Masaharu Assistant, Fuculty of Engineering and Design Kyoto Institute of Technology, 工芸学部, 助手 (70089861)
NAKANISHI Hirishi Associate Professor, Fuculty of Engineering and Design Kyoto Institute of Techno, 工芸学部, 助教授 (00029282)
|Budget Amount *help
¥15,100,000 (Direct Cost: ¥15,100,000)
Fiscal Year 1986: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1985: ¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 1984: ¥10,100,000 (Direct Cost: ¥10,100,000)
It is important to classfy the microfracture mechanisms of composite materials such as the micro-cracking in matrix, the fiber breaking, the delamination and the matrix cracking in pratical use. The microfracture mechanisms are studied by the frequency spectrum, which is most fitted in the AE wave parameters.
The microfracture mechanisms of convential CFRP is studied by using model CFRP. The frequency spectra of the micro-cracking in matrix, the matrix cracking, the debonding between matrix and fibers, and the friction between matrix and fiber or the fiber breaking in model CFRP are 260, 50-100, 150-250 and 270-390 KHz, respectively. The frequency spectra of the matrix cracking, the debonding, and the friction between matrix and fibers or the fiber breaking in the conventional and unidirectional CFRP laminates are 50-100, 150-250, and 270-390 KHz, respectively. The frequency spectrum of conventional and three directional CFRP laminates contains the frequency of 630 KHz, which the model CFRP does not contain and it is generated by the friction between fibers at the delamination.
Next, in the class A-SMC composite material, the frequencies of matrix cracking, the calcium carbonate cracking or the debonding between matrix and calcium carbonate, the debonding between matrix and fibers or the fiber pulling out, and the fiber breaking are 80-180, 240-450, 180-250 and 250-400 KHz, respectively.
It is found that the fracture mechanisms of composite materials can be clarified by the frequency analysis.