Papers by Author: Gi Beop Nam

Abstract: In this study, Jute fibers reinforced polypropylene (JFRP) composites were manufactured by injection molding technique. Prior to fabrication of composites, fiber surface was treated by Alkali and Plasma for a rise in fibers properties. Furthermore, after the alkali treatment attempt plasma treatment for the fiber surface treatment to obtain a batter value. In order to improve the affinity and adhesion between fibers and thermoplastic matrices during manufacturing, Maleic anhydride (MA) as a coupling agent have been employed. Untreated and treated surfaces of jute fibers were characterized using SEM. Tensile and flexural tests were carried out to evaluate the composite mechanical properties. Tensile test indicated that 3% of the alkali treatment and 2min plasma treatment fiber has highest tensile strength.

Abstract: This research makes comparisons of empirical fatigue-lives between AC8A Al alloy and the metal matrix composites (Al/Al2O3, Al/Al2O3/Al2O3p), and also includes comparisons of fatigue-lives between empirical fatigue-lives and estimated fatigue-lives from regular-periodic load testing, acoustic emission (AE) method to predict fatigue-crack initiation before visible in sight and SEM (Scanning Electron Microscope) photographs of each material. According to the test results of the notched specimen, the fatigue life of the hybrid metal matrix composites and the metal matrix composites, which are more brittle than the base matrix was shorter than that of the base matrix under both types of loads. In addition, the fatigue-life estimated from the damage summation method and that from experiments at random loads were fairly identical.