Mechanical property and meso-structure assessment of Ti6Al4V parts as a function of high-speed selective laser melting practice (Additive Manufacturing)
type: CreativeWork
description: The use of titanium and titanium alloys, particularly titanium-6-aluminium-4-vanadium (Ti6Al4V), manufactured by 3D printing, also known as additive manufacturing, is fast evolving in several industries including the aerospace industry, medical industry, and the automotive industry. At present, titanium parts fabricated by additive manufacturing techniques such as the selective laser melting practice are built at conventional laser scan speeds typically between 0.1 m/s and 1 m/s. This project is focused on investigating the influence of high laser scan speeds on the microstructure and mechanical properties of Ti6Al4V fabricated by the selective laser melting technique. Building material at much higher scan speeds allows for a higher rate of productivity and efficiency as more parts can be built in a shorter space of time. The aim of this project is to ensure that the integrity and mechanical behaviour of the Ti6Al4V parts at the high scan speeds is still maintained by investigating whether acceptable mechanical properties are still achieved when material is built at higher scan speeds. The material tested in this project was built by the selective laser melting (SLM) technique at four different high scan speeds namely 5.75 m/s, 6.0 m/s, 6.25 m/s and 6.5 m/s. The material for mechanical testing consisted of tensile specimens and compact-tension (CT) specimens for fracture toughness (FT) testing and fatigue crack growth rate (FCGR) testing respectively. The same material was used for microstructure analysis. Furthermore, the tensile specimens were fabricated in different build orientations namely X-TA, Y-TA, and Z-TA to investigate the effect of build orientation on tensile properties. During the SLM process, considerable thermal related stresses develop in the material being built. After fabrication, a heat treatment protocol was therefore applied to the material for stress relief. The material was heated at 600°C for two hours then cooled in air. Tensile testing was…
abstract: The use of titanium and titanium alloys, particularly titanium-6-aluminium-4-vanadium (Ti6Al4V), manufactured by 3D printing, also known as additive manufacturing, is fast evolving in several industries including the aerospace industry, medical industry, and the automotive industry. At present, titanium parts fabricated by additive manufacturing techniques such as the selective laser melting practice are built at conventional laser scan speeds typically between 0.1 m/s and 1 m/s. This project is focused on investigating the influence of high laser scan speeds on the microstructure and mechanical properties of Ti6Al4V fabricated by the selective laser melting technique. Building material at much higher scan speeds allows for a higher rate of productivity and efficiency as more parts can be built in a shorter space of time. The aim of this project is to ensure that the integrity and mechanical behaviour of the Ti6Al4V parts at the high scan speeds is still maintained by investigating whether acceptable mechanical properties are still achieved when material is built at higher scan speeds. The material tested in this project was built by the selective laser melting (SLM) technique at four different high scan speeds namely 5.75 m/s, 6.0 m/s, 6.25 m/s and 6.5 m/s. The material for mechanical testing consisted of tensile specimens and compact-tension (CT) specimens for fracture toughness (FT) testing and fatigue crack growth rate (FCGR) testing respectively. The same material was used for microstructure analysis. Furthermore, the tensile specimens were fabricated in different build orientations namely X-TA, Y-TA, and Z-TA to investigate the effect of build orientation on tensile properties. During the SLM process, considerable thermal related stresses develop in the material being built. After fabrication, a heat treatment protocol was therefore applied to the material for stress relief. The material was heated at 600°C for two hours then cooled in air. Tensile testing was…
author: Nyakunu, Chenesai
keywords: Engineering
date published: 2022
date modified: 2026-07-22T22:23:19Z
provider: University of Cape Town
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Department of Mechanical Engineering

PropertyValue
property ID: Handle
value: http://hdl.handle.net/11427/37711