Effects of manufacturing defects on thermoformed product quality
In this study, 5% and 15% in weight carbon fiber reinforced polypropylene (PP) sheets were formed under appropriate vacuum and temperature conditions by using truncated cone-shaped thermoforming mold. In addition to this, 5% in weight glass fiber reinforced High Density Polyethylene (HDPE) sheets were formed using truncated cone-shaped, cylindrical, and cubic shaped thermoforming molds by thermoforming. Composite sheets used in this work were produced with a laboratory-type plastic extruder which has a screw diameter of 50 mm. In production of HDPE composite sheets, as a reinforcing material, chopped glass fibers (E-glass) which were provided from glass fiber manufacturer SISECAM A.S. Company were used. Using the same procedure PP (Borealis BE50-7032) thermoplastic granules were used as a matrix material in production of carbon fiber composite sheets. In carbon fiber reinforced sheets, chopped fibers were added during manufacturing. After thermoforming, composite semi-products were examined by visual inspection. Visual defects that affect product quality were obtained. Also carbon fiber distribution was investigated on different sections which were taken from the thermoformed semi-products by Scanning Electron Microscopy (SEM). Through this experimental study, it is aimed to investigate the effect of defects during plastic extrusion on thermoformed product quality.
Effects of manufacturing defects on thermoformed product quality
In this study, 5% and 15% in weight carbon fiber reinforced polypropylene (PP) sheets were formed under appropriate vacuum and temperature conditions by using truncated cone-shaped thermoforming mold. In addition to this, 5% in weight glass fiber reinforced High Density Polyethylene (HDPE) sheets were formed using truncated cone-shaped, cylindrical, and cubic shaped thermoforming molds by thermoforming. Composite sheets used in this work were produced with a laboratory-type plastic extruder which has a screw diameter of 50 mm. In production of HDPE composite sheets, as a reinforcing material, chopped glass fibers (E-glass) which were provided from glass fiber manufacturer SISECAM A.S. Company were used. Using the same procedure PP (Borealis BE50-7032) thermoplastic granules were used as a matrix material in production of carbon fiber composite sheets. In carbon fiber reinforced sheets, chopped fibers were added during manufacturing. After thermoforming, composite semi-products were examined by visual inspection. Visual defects that affect product quality were obtained. Also carbon fiber distribution was investigated on different sections which were taken from the thermoformed semi-products by Scanning Electron Microscopy (SEM). Through this experimental study, it is aimed to investigate the effect of defects during plastic extrusion on thermoformed product quality.
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