Thermoviscoelastic Behavior of Film-Insert-Molded Parts Prepared under Various Processing Conditions

• Published in: Macromolecular materials and engineering Vol. 293; no. 12; pp. 969 - 978
• Main Authors: Kim, Seong Yun, Lee, Seung Hwan, Baek, Soo Jin, Youn, Jae Ryoun
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 10.12.2008; WILEY‐VCH Verlag; Wiley
• Subjects: annealing; Applied sciences; Exact sciences and technology; injection molding; Injection moulding; Machinery and processing; Moulding; Plastics; Polymer industry, paints, wood; Technology of polymers; viscoelastic behavior; warpage; Stress analysis; Polymer blends; Warping; Viscoelastic strain; viscoelastic behavior; Multiple layer; Methyl methacrylate polymer; Experimental study; Property processing relationship; annealing; Decoration; warpage; ABS; Three dimensional flow; Depth profile; Injection molding; Numerical simulation; Polycarbonate; Residual stress
• ISSN: 1438-7492; 1439-2054
• DOI: 10.1002/mame.200800193

Film‐insert‐molded (FIM) tensile specimens were prepared under various molding conditions to investigate the effects of wall temperature and packing pressure on the residual stress distribution and thermoviscoelastic deformation. The warpage of the specimen increased with increasing mold‐wall temperature difference and decreased with increasing packing pressure. The FIM specimens produced with unannealed films showed the warpage reversal phenomenon (WRP) during annealing and the degree of WRP was affected significantly by the molding conditions and thermal shrinkage of the film. The warpage of the specimen was predicted by three‐dimensional flow and stress analyses and the prediction was in good agreement with the experimental results.