Production of a Permanent Mold Gravity Die Cast A356.0 Aluminum Alloy Motorbike Shock Absorber through Casting Simulation

Abstract:

Motorbike shock absorbers of gravity die cast aluminum A356.0 alloy were being imported in the as-cast condition and later on machined at local foundries and workshops by sub-vendors to achieve the required dimensions and on many occasions a nearly complete solid block was cast and machined to achieve the desired shape but this process not only lowered the metallic yield but also the high machining costs and time required made it very uneconomical. Motorbike shock absorbers are critical vehicle components which are always under load and must never fail suddenly without warning therefore they need to be free of defects like shrinkage and micro-porosity. The thin wall thickness of 6mm and troublesome nature of cores required makes this component quite difficult for the conventional metal caster. The current research paper deals with the methoding, die designing, modeling and simulation, optimization and finally casting of these components following the data produced by the former. Initially a single piece per mold was suggested but later on considering the economics of the project two pieces i.e. left and right were recommended to be cast from a single sprue in each die with a vertically parted permanent die mold. For the methoding calculations the Thermal modulus has been used instead of the conventional casting modulus and for gating the naturally pressurized system is incorporated. Throughout the simulation process a significant number of iterations were made to achieve the final design which ensured a laminar flow of liquid aluminum below the critical velocity limit; the actual die casting results yielded good comparison with the simulation studies showing shrinkage cavity away from the risers and micro-porosity only in ingates.

• Periodical: Key Engineering Materials (Volume 659)
• Pages: 676-680
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.659.676
• Online since: August 2015
• Authors: Muhammad Saqib Qayyum*
• Keywords: Computational Methoding, Die Cast, Modeling, Shock Absorbers, Simulation

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