Effects of Interlaminar Morphology on the Fracture Toughness of Carbon Fiber/Epoxy Laminated Composites

• Main Authors: Kuo-Liang Mao, 毛國亮
• Other Authors: Professor Eamor M. Woo
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/54696773728934791894

碩士 === 國立成功大學 === 化學工程研究所 === 83 === Composite materials often fail by delamination. In this study, two thermoplastic polymers, poly(ether imide) (PEI) and poly( hydroxy ether of bisphenol A) (PHENOXY) were used as particulate interlaminar toughening agents in graphite/epoxy system. Mode-I and Mode-II delamination toughness was characterized using the Mode-I double-cantilever beam (DCB) and the Mode-II end-notched flexure (ENF) test specimens. The delamination surface was examined by a scanning electron microscope (SEM) to investigate the morphology and fracture mechanism. The results revealed that as the PEI contents were increased, GIC and GIIC increased. GIC was improved from 167 to 527J/m2 at 1mm/min crosshead rate and GIC was improved from 146 to 493J/m2 at a higher crosshead rate of 10mm/min. GIIC improved from 293 to 1297J/m2. In PHENOXY interlaminar toughened system, GIC was almost the same as PEI toughened system, but GIIC was much lower. The fracture surfaces of PEI toughened system showed phase-inversed morphology, and the toughening mechanism was ductile yielding of PEI.