The Effects of Nodularity Distribution on Vertical Configuration Mould for Automotive Ductile Iron Casting

Abstract:

Mechanical properties of ductile iron casting are strongly inclined with metal matrix microstructure, graphite elements presence and impurities rate. Increasing in the number of graphite elements near to sphere shape (nodule), more superior mechanical properties will be realized. Automotive castings normally produced in mass production due to high demand; vertical moulding configuration is one of the best options for producing mass quantity automotive castings. This study aim to discover either the vertical moulding configuration will affects the nodularity properties distribution for different cavity position in the mold. In this study, ductile iron disc brake castings have been produced by in-mold Mg treatment using vertical parted molding method. Samples from different cavity position were taken and analyzed their nodularity distribution. Image processing computer procedure-Lieca was used to characterize the graphite morphology of the samples. The result shows that the different cavity position of vertical orientation disc brake casting produced dissimilar distribution of graphite. Higher position of cavity has higher nodule count and round graphite.

• Periodical: Advanced Materials Research (Volumes 129-131)
• Pages: 1059-1063
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.129-131.1059
• Online since: August 2010
• Authors: Alias Mohd Saman, Abdul Halim Abdullah, Mohd Asri Mohd Nor, Mohd Hasbullah Idris
• Keywords: Automotive Castings, Brake Disc, Ductile Iron, Graphite Elements, Nodule Count

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