Heat Transfer and Phase Formation through EBM 3D-Printing of Ti-6Al-4V Cylindrical Parts Vladimir Popov a , Alexander Katz-Demyanetz a , Menachem Bamberger b a Israel Institute of Metals, Technion R&D Foundation, Technion City, Haifa 32000, Israel b Department of Materials Science & Engineering, Technion – Israel Institute of Technology, Technion City, Haifa 32000, Israel Keywords: Additive manufacturing, Heat transfer, Electron beam melting, EBM, Simulation of 3d- printing, Ti-6Al-4V Abstract. 3d-printing or additive manufacturing (AM) is a group of novel intensively developed production processes, through which a "printed" object is fabricated layer-by-layer in a desired intricate geometrical shape, followed by joining it into a monolithic bulk by means of Electron Beam (EB) or Laser Beam (LB) melting. The present study concentrates on the production of simple-shaped (cylindrical) Ti-6Al-4V alloy samples by Electron Beam Melting (EBM). The effect of heat transfer conditions on the microstructure and properties obtained has been investigated. Heat transfer modelling and simulation were done utilizing the ABAQUS software package. The microstructure of the obtained material has been characterized by means of SEM and XRD. Hardness and microhardness have been also determined and correlated with the simulation results. Introduction Ti-6Al-4V – classic aerospace alloy Pure titanium is an allotropic element, therefore, it has more than one crystallographic structure, which changes with temperature [1] from a BCC structure (β-phase) within the high temperature range to a HCP structure (α-phase), at low temperatures [1]. This phase transition occurs at 883°C, as the transition temperature is highly affected by the alloying elements [2]. The stabilization of the α-phase is made by raising the temperature to a temperature where this phase is stable, and the stabilization of β-phase is made by decreasing the temperature to a temperature where the latter is stable [1]. Titanium alloys may be classified into five large categories, based on their chemical composition and microstructure at room temperature: α-alloys, near α-alloys, (α+β) alloys, metastable β-alloys and β-alloys [3]. Out of all the (α +β) alloys, Ti-6Al-4V is the most commonly used one. Ti-6Al-4V is a classic aerospace alloy and the most popular powder composition for metallic 3D-printing. Its properties are strongly related to the microstructure [2]. Generally, a lamellar microstructure improves the fatigue crack propagation, creep and oxidization resistance. Moreover, a globular structure is preferred for strength and ductility [4, 5]. New layer Pre-heating Melting The platform goes down Fig. 1. Arcam EBM manufacturing process. Defect and Diffusion Forum Submitted: 2017-07-13 ISSN: 1662-9507, Vol. 383, pp 190-195 Revised: 2017-10-15 doi:10.4028/www.scientific.net/DDF.383.190 Accepted: 2017-10-26 © 2018 Trans Tech Publications, Switzerland Online: 2018-02-28 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, www.scientific.net. (#108739298-19/06/18,11:07:05)