Studies on the fracture process and morphology of fractured surface in wood and wood-based materials.

Research Project

Project/Area Number	60302083
Research Category	Grant-in-Aid for Co-operative Research (A)
Allocation Type	Single-year Grants
Research Field	林産学
Research Institution	Kyoto University
Principal Investigator	NOBUCHI Tadashi (1986) Faculty of Agriculture, Kyoto University, Instructor, 農学部, 助手 (50026499) 佐伯浩京都大学, 農学部, 助教授
Co-Investigator(Kenkyū-buntansha)	FURUKAWA Ikuo Faculty of Agriculture, Tottori Univ., Instructor, 農学部, 助手 (50032313) IMAMURA Yuji Wood Research Inst., Kyoto University, Instructor, 木材研究所, 助手 (70151686) FURUNO Takeshi Faculty of Agriculture, Shimane Univ., Associate professor, 農学部, 助教授 (90032573) NORIMOTO Misato Wood Research Inst., Kyoto University, Associate professor, 木材研究所, 助教授 (20027163) SAIKI Hiroshi Faculty of Agriculture, Kyoto University, Associate professor, 農学部, 助教授 (40026498)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥6,200,000 (Direct Cost: ¥6,200,000) Fiscal Year 1986: ¥2,500,000 (Direct Cost: ¥2,500,000) Fiscal Year 1985: ¥3,700,000 (Direct Cost: ¥3,700,000)
Keywords	Wood / Wood-based materials / Failure / Fracture process / Fracture morphology / Fractography / Fractured surface / 疲労
Research Abstract	Fractographic investigations have been carried out in many fields of wood science and technology. The cooperative investigators from those fields had meetings on the subject, and examined the important problems concerned with this subject in their fields. 1) Two basic types of failure are found in wood specimens mechanically damaged. One is failure in which complete or incomplete separations occur between elements or within each element in wood, the other is failure in which buckling or bending occur in the wall of elements. Typical forms of each failure type were illustrated in the report. 2) Early wood and late wood in softwood showed quite different failure forms. Moisture content in wood and temperature during loading considerably affected the failure forms and structure of fractured surfaces. 3) Fatigue failure forms by repeated bending depended on vibration methods(one-sided or both-sided). 4) A clear difference was found between bonding with phenolic resin adhesive and that with urea. 5) The failure forms of decayed wood were remarkably different from those of sound wood. The kind of decay(ex. white-rot and brown-rot) affected the structure of fractured surfaces in decayed wood. 6) Technical terms used in fractography of wood and wood-based materials were listed in the report.