Document Type
Thesis - University Access Only
Award Date
2006
Degree Name
Master of Science (MS)
Department / School
Mechanical Engineering
Abstract
Warpage is one of the most common defects of a plastic product in the polymer injection molding process. It is attributed to the differential shrinkage after the part is ejected from the die cavity due to the nonlinear material property of the polymer, improper design of the cooling system, geometry of the part and the related process parameters. In this paper, the warpage formation of a plastic part in the cooling stage of the polymer injection molding process was simulated by using finite element analysis (FEA). A three-dimensional FEA model for a nonlinear polymer material (polypropylene copolymer) with a thermal-structural sequential coupled approach was developed. The effects of mold close time and layout of cooling system on the dimension and shape of a part were investigated. Industrial experiments for the different mold closing time (t = 25s, 30s, 35s, 40s, 45s, 50s, 55s) were conducted. The simulation results were compared with the experimental results. The sequential coupled approach is effective in predicting warpage in polymer injection molding process.
Library of Congress Subject Headings
Injection molding of plastics
Plastics -- Defects -- Computer simulation
Format
application/pdf
Number of Pages
88
Publisher
South Dakota State University
Recommended Citation
Ramamurthy, Sridhar P., "Computer Simulation of Warpage Formation in Injection Molding of a Plastic Step Pad" (2006). Electronic Theses and Dissertations. 1298.
https://openprairie.sdstate.edu/etd2/1298