Evaluation of resin flow and fiber orientation around injection nozzle in injection molding by particle method

Resin and fiber flow around the injection nozzle of a flat mold in injection molding was analyzed using the particle method that can easily track resin and fiber flow, and the effects of injection position of resin and fiber and injection time on resin and fiber flow behavior were evaluated. Resin flow was unstable near the flow front but was stable after the flow front was passed. Regarding fiber flow, many fibers were oriented perpendicular to the flow direction in the mold width direction. On the other hand, fibers were randomly oriented in the mold thickness direction. The difference in orientation between the thickness direction and the width direction is considered to be caused by the resin injected from the injection nozzle spreading in the width direction while decreasing its velocity. These results are likely to be greatly affected by parameters such as mold shape and injection speed, and further evaluation of these parameters is needed.