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Journal of Mechanical Science and Technology

, Volume 30, Issue 11, pp 5143–5152 | Cite as

Minimization of variation in volumetric shrinkage and deflection on injection molding of Bi-aspheric lens using numerical simulation

  • R. Joseph Bensingh
  • S. Rajendra Boopathy
  • C. Jebaraj
Article

Abstract

The profile of a bi-aspheric lens is such a way that the thickness narrows down from center to periphery (convex). Injection molding of these profiles has high shrinkage in localized areas, which results in internal voids or sink marks when the part gets cool down to room temperature. This paper deals with the influence of injection molding process parameters such as mold surface temperature, melt temperature, injection time, V/P Switch over by percentage volume filled, packing pressure, and packing duration on the volumetric shrinkage and deflection. The optimal molding parameters for minimum variation in volumetric shrinkage and deflection of bi-aspheric lens have been determined with the application of computer numerical simulation integrated with optimization. The real experimental work carried out with optimal molding parameters and found to have a shallow and steep surface profile accuracy of 0.14 and 1.57 mm, 21.38-45.66 and 12.28-26.90 μm, 41.56-157.33 and 41.56-157.33 nm towards Radii of curvatures (RoC), surface roughness (Ra) and waviness of the surface profiles (profile error Pt), respectively.

Keywords

Bi-Aspheric lens Injection molding Numerical simulation Taguchi and variation in volumetric shrinkage 

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Copyright information

© The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • R. Joseph Bensingh
    • 1
  • S. Rajendra Boopathy
    • 2
  • C. Jebaraj
    • 3
  1. 1.Central Institute of Plastics Engineering and TechnologyChennaiIndia
  2. 2.College of EngineeringAnna UniversityChennaiIndia
  3. 3.Vellore Institutes of TechnologyChennaiIndia

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