MICROSTRUCTURAL ANALYSIS AND MECHANICAL PROPERTIES OF LM6 ALLOY PROCESSED BY COOLING SLOPE CASTING

Mohd Shukor Salleh; Nurul Naili Mohamad Ishak; Mohd Azizul Hikmi Safian; Saifudin Hafiz Yahaya

Mohd Shukor Salleh Universiti Teknikal Malaysia Melaka
Nurul Naili Mohamad Ishak Universiti Teknikal Malaysia Melaka
Mohd Azizul Hikmi Safian Universiti Teknikal Malaysia Melaka
Saifudin Hafiz Yahaya Universiti Teknikal Malaysia Melaka

Abstract

In this study, LM6 aluminium alloy were processed by semisolid metal processing via cooling slope casting technique. The primary objectives of this study were to investigate the most effective cooling slope parameter that affect the globulization of LM6 alloy. The mechanical properties of the alloy after the process were also discussed. The microstructural characterization was done by optical microscope (OM) while for mechanical test; tensile test and hardness test were performed. Some of the cooling slope samples were subjected to T6 heat treatment and the effect of heat treatment was discussed. The results obtained reveals that cooling slope casting produce a non-dendritic structures compared to conventional casting. The results also revealed that at pouring temperature of 660°C and 300 mm cooling slope length, the LM6 alloy exhibits a spherical microstructural feature due to all dendritic structures were replaced by ɑ-Al globule and rosette. For mechanical properties, it showed that tensile strength and hardness value were increased significantly as it process by cooling slope casting as compared to conventional casting. After T6 heat treatment the tensile strength and Vickers hardness increased about 23% and 7% respectively for a sample poured at 660°C and 300 mm slope length in cooling slope casting.

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Author Biographies

Mohd Shukor Salleh, Universiti Teknikal Malaysia Melaka

Dr Mohd Shukor Salleh received his Bachelor Degree in Manufacturing Engineering from Universiti Kebangsaan Malaysia (UKM) and Master’s degree in Manufacturing Systems Engineering from Coventry University United Kingdom. He completed his Doctoral course in Mechanics and Materials Engineering in Universiti Kebangsaan Malaysia. He started his career at Panasonic Semiconductor Discrete Devices (M) Sdn Bhd as a process engineer. He joined the Faculty of Manufacturing Engineering at Universiti Teknikal Malaysia Melaka (UTeM) as a lecturer since 2006. Presently, he is actively involved in teaching, consultation, and research work with various manufacturing engineering projects.

Nurul Naili Mohamad Ishak, Universiti Teknikal Malaysia Melaka

Department of Manufacturing Process

Mohd Azizul Hikmi Safian, Universiti Teknikal Malaysia Melaka

Department of Manufacturing Process, Universiti Teknikal Malaysia Melaka

Saifudin Hafiz Yahaya, Universiti Teknikal Malaysia Melaka

Department of Manufacturing Design, Universiti Teknikal Malaysia Melaka

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