Study on the Surface Treatment of Special Screw for Light Guiding Plate’s Precision Injection Molding

Abstract:

Defects such as black spots and yellow surfaces appeared in the process of injection molding light guiding plate as a result of the failure surfaces of the screw and screw tip. To choose and optimize the solutions of different surface treatments of the special screw for light guiding plate, the stripping performance testing platform was established. The experimental results showed that TiN and TiAlN or similar coatings by physical vapor deposition could significantly reduce the adhesion force between polycarbonate (PC) and different coatings. Through surface topography analysis of diversified coatings with SEM and AFM, TiAlN coatings represented the excellent surface quality of its smoothness, continuum, and low surface wave. To enhance the bonding force between the molding screw and coatings, TiAlN/Cr and TiAlN/Ti multi-films was developed which owned much more firm bonding force than TiAlN and good surface quality to be suitable for the special screw for manufacturing light guiding plate.

• Periodical: Advanced Materials Research (Volume 221)
• Pages: 123-128
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.221.123
• Online since: March 2011
• Authors: Gang Gou, Peng Cheng Xie, Zhen Xing Wen, Yu Mei Ding, Wei Min Yang
• Keywords: Injection Molding, Light Guide Plate, PVD, Surface Treatment, TiAlN

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