Prof. Nao-Aki NodaKyushu Institute of Technology, Japan
Speech Title: Intensity of Singular Stress Fields (ISSFs) in Pull-out Test and Micro-bond Test
Abstract: In fiber reinforced composites, the fiber/matrix combination produces certain mechanical properties that cannot be achieved by either of the constituents acting alone. Pull-out and micro-bond tests are commonly used to investigate the interface properties by using the average interface stress without considering the singular stress fields (ISSFs). In this talk, therefore, the ISSF at the fiber entry/end points is discussed since the ISSF may control the interface debonding for pull-out and micro-bond tests. It is found that the ISSFs of pull-out test can be predicted from the ISSF of the micro-bond test conveniently used because the ISSF of micro-bond test is about 1.5 times of the ISSF of pull-out test under the same fiber geometry. Suitable testing geometry is proposed for micro-bond test since the ISSF is very sensitive to the knife gap under the small dimension commonly used.
Key words: Fiber reinforced composites, Micro-bond test, Fiber Pull-out, Intensity of singular stress field (ISSF), Fiber/Matrix interface
Biography: Nao-Aki Noda received his Ph.D. degree in Mechanical Engineering from Kyushu University, Japan in 1984. He has been doing research and teaching at Kyushu Inst. Tech., Kitakyushu, Japan, 1984-87, He is an author of Theory of Elasticity useful for engineers and a co-author of Safety Engineering for Workers in Industry and other several books. He is a co-editor of Stress Intensity Factors Handbook, vol. 4 & 5, Advances in Finite Element Analysis for Computational Mechanics. He is a recipient of Outstanding Paper Medal of Japan Soc. Tech. Plasticity, Sokeizai Industry Technology award from the Materials Process Tech. Ctr., a fellow of JSME (Japan Soc. Mech. Engrs.) and a fellow of JSAE (Soc. Automotive Engrs. Japan), JSMS Award for Academic Contribution and JSME Materials and Mechanics Division Award. He Achievements include researches in stress analysis for notched material testing specimens, and development for large ceramics structures used for steel manufacturing machinery and special bolt-nut connection improving anti-loosening and fatigue strength.