Basic Research for Microscopic Strength of Composite Material by Mechanics and Spectroscopy

Research Project

Project/Area Number	01460088
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	機械材料工学
Research Institution	Tokyo Institute of Technology
Principal Investigator	KOIZUMI Takashi Tokyo Institute of Technology, Faculty of Engineering, Professor., 工学部, 教授 (90016337)
Co-Investigator(Kenkyū-buntansha)	NOTOMI Mitsuo Tokyo Institute of Technology, Faculty of Engineering, Researcher Associate, 工学部, 助手 (70218288) INOUE Hirotsugu Tokyo Institute of Technology, Faculty of Engineering, Researcher Associate, 工学部, 助手 (90193606)
Project Period (FY)	1989 – 1990
Project Status	Completed (Fiscal Year 1990)
Budget Amount *help	¥3,900,000 (Direct Cost: ¥3,900,000) Fiscal Year 1990: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1989: ¥3,400,000 (Direct Cost: ¥3,400,000)
Keywords	Composite Material / IR-Spectroscopy / Fracture Strength / Degradation / 熱弾性応力測定法
Research Abstract	(1) Using two kinds of materials for Poisson's ratio and Young's modulus, the mechanical models of composite material as three laminated were made. Firstly, tension tests were carried out and stress-strain curves were obtained. Secondly, fatigue tests were carried out and SN-curves were taken. After that, the fracture surface of the specimens were observed. We discussed the behavior of fracture. (2) When the mechanical model of composite material was loaded, stress occurring in it was calculated. On microscopic structure, Young's modulus and Poisson's ratio are not constants in a composite material. We proposed an inverse analysis method using the deflection of a beam given by experiments and to estimate the Young modulus distribution in composite materials. The basic equation used elemental beam theory and the calculation method used the optimization method using DFP-method. Further, these results were compared with the results obtained by a finite element method analysis, and confirmed the effectivity of the resolution. (3) Using some kinds of polymer materials the model experiments were conducted and degradation of polymer composite matrix was investigated. After each matrix was exposed to constant temperature and moisture in the chamber a specified, tension tests and Charpy impact tests were conducted. The fracture surface of these specimens were observed by microscopy and electric microscopy and we discussed the behavior of fracture. Measurements of weight and moisture using the infra-red moisture equipment were conducted. Moreover by infra-red spectroscope, which was purchased last year, the changes of chemical strucutre of matrix due to degradation were observed. We admitted the relation between mechanical properties and IR spectra.