一方向炭素繊維強化アルミニウムの繊維軸に垂直な方向の混合モード下での破壊挙動

抄録

Transverse failure behaviors of unidirectionally-reinforced continuous carbon fiber (M40) reinforced aluminum (A1100) matrix composite under crack opening (mode I ), forward shearing (mode II), and their combined mode have been investigated. A modified form of ARCAN'S fixture was used to obtain mixed mode fracture behavior and fracture toughness. Transverse teusile elastic modulus and strength of the composite were also obtained.
Results showed that the elastic modulus of the composites was 23.5 GPa and was smaller than that of the matrix. The transverse tensile strength was 18 MPa and was approximately 1/10 of longitudinal one. It was found that the values of K_Ic was larger than K_IIc. The fracture behavior of the composite varied with the ratio of applied mode I and mode II component. The K_I - K_II relation did not obey theoretically-obtained quadratic relation. This behavior was explained by crack shielding mechanism due to crack bridging by thin composite wire. The efficacy of crack shielding varied with the-ratio of applied mode I and mode II component.