Scanning electro-microscopy of alloys

• Main Author: Yong, Jovi Min
• Other Authors: Shu Dong Wei, David
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Materials::Metallic materials::Alloys
• Online Access: http://hdl.handle.net/10356/76671
• Institution: Nanyang Technological University

Magnesium and its alloys have been an interest in automotive, aerospace and electronics industry for its light weight properties. However, due to its hexagonal closed packed (HCP) crystal structure, its deformation mechanism is much more complicated compared to other conventional metals. In recent years, various research have been done to understand the mode of deformation of magnesium and its alloys. The aim of this project is to contribute to these studies. The results from this project could aid in maximizing the usage of magnesium alloys, especially when weight is a crucial factor in certain applications. This project investigates the deformation mechanism and effect of strain rate on magnesium alloy, AZ31B. Two specimens have undergone deformation at varying strain rates (0.001/s and 700/s) by the Compression Split Hopkinson Pressure (SHP) bar test, at room temperature. The microstructural evolution of these specimens were viewed under the Optical Microscope and the Scanning Electron Microscope. It has been observed that twinning is the predominant mode of deformation at both low and high strain rates. There were also presence of slip bands observed at low strain rate, which was absent at high strain rate. Furthermore, the twins nucleated and propagated in size as strain rate increased.