The Fiber Damage and Mechanical Properties of Short-fiber Reinforced Composite Depending on Nozzle Size Variations in Injection/Mold Sides

단섬유강화 복합재료에서 사출측/금형측 노즐 크기 변화에 따른 섬유손상 및 기계적 성질

Lee, In-Seop;Lee, Dong-Ju

  • Published : 2001.04.01


The mechanical properties of short carbon/glass fiber reinforced polypropylene are experimentally measured as functions of fiber content and nozzle diameter. Also, these properties are compared with the survival rate of reinforced fibers and fiber volume fraction using image analysis after pyrolytic decomposition. The survival rate of fiber aspect ratio as well as fiber volume fraction is influenced by injection processing condition, the used materials and mold conditions such as diameter of nozzle, etc. In this study, the survival rate of fiber aspect ratio is investigated by nozzle size variations in injection/mold sides. It is found that the survival rate of glass fiber is higher that the survival rate of glass fiber is higher than that of carbon fiber. Both tensile modulus and strength of short-fiber reinforced polypropylene are improved s the fiber volume fraction and nozzle diameter are increased.


Injection Molding;Fiber Damage;Fiber Volume Fraction;Aspect Ratio;Pyrolytic Decompositon;Survival Rate;Nozzle Size;Short Fiber


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