IMPROVEMENT IN ORIENTATION MEASUREMENT FOR SHORT AND LONG FIBER INJECTION MODLED COMPOSITES

Short and long fiber reinforced thermoplastics are a feasible alternative to develop lightweight materials for semi-structural and structural applications, respectively. These composites present a layered structure showing a complex tridimensional structure along the molding, created during the forming stage. The details of short fiber orientation in a center-gated disk with diameter of 1.38 mm were obtained in several regions including the gate and advancing front. Several modifications were introduced in the method of ellipses to obtain unambiguous orientation of 30 % short glass-fiber PBT. The unambiguous Arθ component was successfully obtained with the modified method. The results also showed an asymmetric distribution of fiber orientation that gradually washout as the flow progress. In addition, the initial orientation measured at the gate presented a fiber distribution different from the random orientation that is assumed in literature for a center-gated disk. Additionally, the initial results of this modified method to assess the complex structure of a 30 % long glass-fiber PP end-gated plaque are shown.

[1]  P. Carreau,et al.  Rheological properties and microstructural evolution of semi-flexible fiber suspensions under shear flow , 2010 .

[2]  S. L. Roux,et al.  A simplified method to determine the 3D orientation of an injection molded fiber‐filled polymer , 2008 .

[3]  D. Dreossi,et al.  Local anisotropy analysis of injection moulded fibre reinforced polymer composites , 2008 .

[4]  Ba Nghiep Nguyen,et al.  Fiber Length and Orientation in Long-Fiber Injection-Molded Thermoplastics — Part I: Modeling of Microstructure and Elastic Properties , 2008 .

[5]  A. Cunha,et al.  Fiber Orientation in Injection Molding With Rotating Flow , 2008 .

[6]  A. Latz,et al.  Flow-driven orientation dynamics of semiflexible fiber systems , 2007 .

[7]  S. Ikeda,et al.  Unambiguous Determination of 3D Fiber Orientation Distribution in Thermoplastic Composites Using SAM Image of Elliptical Mark and Interference Fringe , 2005 .

[8]  Steven Nutt,et al.  Direct observation and measurement of fiber architecture in short fiber-polymer composite foam through micro-CT imaging , 2004 .

[9]  Pierre Baylou,et al.  Fiber orientation measurements in composite materials , 2004 .

[10]  P. Hine,et al.  Fiber orientation structures and mechanical properties of injection molded short glass fiber reinforced ribbed plates , 2004 .

[11]  G. Zak,et al.  Estimation of Three-Dimensional Fibre-Orientation Distribution in Short-Fibre Composites by a Two-Section Method , 2001 .

[12]  B. Mlekusch,et al.  Fibre orientation in short-fibre-reinforced thermoplastics II. Quantitative measurements by image analysis , 1999 .

[13]  B. Mlekusch,et al.  Fibre orientation in short-fibre-reinforced thermoplastics I. Contrast enhancement for image analysis , 1999 .

[14]  K. Jansen,et al.  Shrinkage Anisotropy in Fiber Reinforced Injection Molded Products , 1998 .

[15]  Dominique Lafon,et al.  Determination of 3D fiber orientations in reinforced thermoplastics, using scanning electron microscopy , 1995 .

[16]  Charles L. Tucker,et al.  Stereological measurement and error estimates for three-dimensional fiber orientation , 1992 .

[17]  Suresh G. Advani,et al.  The Use of Tensors to Describe and Predict Fiber Orientation in Short Fiber Composites , 1987 .

[18]  R. J. Crowson,et al.  A study of the effect of injection speed on fibre orientation in simple mouldings of short glass fibre-filled polypropylene , 1978 .

[19]  E. Hinch.  The distortion of a flexible inextensible thread in a shearing flow , 1976, Journal of Fluid Mechanics.

[20]  C N Eberhardt,et al.  Microscopy techniques for materials science , 2002 .

[21]  Peter Hine,et al.  Measuring the fibre orientation and modelling the elastic properties of injection-moulded long-glass-fibre-reinforced nylon , 1995 .