PROBLEM TO BE SOLVED: To provide a method of using a composite laminate exhibiting a quasi-isotropic property in order to arrest and/or redirect propagation of cracks and/or delamination generated in a laminate.SOLUTION: The invention provides a composite laminate 18 which is reinforced with unidirectional fibers, yet exhibits quasi-isotropic properties. An airframe 20 includes a composite skin 22 joined to frame members 24 and reinforced by stiffeners 26. The frame members 24 reinforce the skin 22 in the circumferential direction. The stiffeners 26 strengthen the airframe 20 including the skin 22 in the longitudinal direction. An interior 25 of the airframe 20 is pressurized, resulting in a force exerted on the skin 22 in the radial direction as indicated by an arrow 28. A quasi-isotropic nature is acquired by stacking ply orientations during layup. The difference or mismatch in Poisson's ratio between the adjacent plies is approximately 15 to 40%. The mismatch causes the quasi-isotropic nature of the laminate, and a crack and/or delamination is arrested by redirecting or turning the crack/delamination.SELECTED DRAWING: Figure 1

    【課題】ラミネート材に生じた亀裂及び/又は剥離の伝播を止める及び/又は伝播の方向を変えるために、準等方性の特性を示す複合ラミネート材を用いる方法を提供する。【解決手段】一方向性ファイバで補強され、且つ準等方性を示す複合ラミネート材18を提供する。機体20は、フレーム部材24に結合されて、補強材26により補強される複合外板22を含む。フレーム部材24は円周方向に外板22を補強する。補強材26は縦方向の外板22を含む機体20を強化する。機体20の内部25は加圧されて、外板22に対し、矢印28に示される放射方向の力を生じさせる。準等方性の性質は、成層の間にプライの配向を積み重ねることで獲得される。隣接し合うプライ間のポアソン比の差異又は不一致は、約15〜40%である。この不一致によりラミネート材に準等方性の性質が生じ、亀裂及び/又は剥離の方向を変え、又は曲げることにより、亀裂/剥離を止める。【選択図】図1


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    Title :

    COMPOSITE STRUCTURES EMPLOYING QUASI-ISOTROPIC LAMINATES


    Additional title:

    準等方性ラミネート材を用いた複合構造


    Contributors:

    Publication date :

    2016-02-04


    Type of media :

    Patent


    Type of material :

    Electronic Resource


    Language :

    Japanese


    Classification :

    IPC:    B64C AEROPLANES , Flugzeuge



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