Formation of Titanium Oxide by Thermal-Electrochemical Process on the Blasted Titanium Alloys Substrate Raden Dadan Ramdan 1,a , Joy Rizki Pangestu Djuansjah 2,b , Mohamed Rafiq Abdul Kadir 3,c , Hadi Nur 4,d , Esah Hamzah 2,e 1 Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung, West Java, Indonesia 40132 2 Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Skudai, Johor 81310 Malaysia 3 Faculty of Biomedical Engineering and Health Science, Universiti Teknologi Malaysia, Skudai, Johor 81310 Malaysia 4 FInstitut Ibnu Sina For Fundamental Science, Universiti Teknologi Malaysia, Skudai, Johor 81310 Malaysia a dadan@material.itb.ac.id, b joy@fkm.utm.my, c rafiqkadie@utm.my, d hadi@kimia.fs.utm.my, e esah@fkm.utm.my Keywords: Titanium oxide, Thermal-electrochemical process, Blasting Abstract. Titanium oxide is believed as one of the key factors that influence the excellent corrosion properties as well as biocompatibility of titanium alloy. In the present research, thermal- electrochemical anodizing processes were performed in order to form thick layer of titanium oxide on titanium alloys (Ti6Al4V) surface. Oxidation temperature, blasting and anodizing voltage were selected as the evaluated parameters process at the present study. It was observed that temperature plays important role in the formation of oxide layer, where the thickness of the oxide increases significantly as temperature increases. However, for the case of oxide layer formed by thermal oxidation at temperature of 950 o C, oxide layer on the non-blasted sample become easily peel off, whereas oxide layer on the blasted sample shows good adhesion properties. In addition, oxide layer on the blasted samples also have thicker layer as compared with oxide on the non-blasted sample. On the other hand, it was observed that further oxidation by anodizing at 43V and 63V create finer oxide layer by the filled up of porosity on the existing oxide layer. However decreasing of oxide layer thickness was also observed after anodizing, which is predicted due to the breaking up the outer oxide layer during anodizing process. Introduction Titanium alloy is among widely used materials for various applications due to its excellent properties. Since the alloy has high strength to weight ratio [1], titanium is used for car components such as spring [2], connecting rods, rocker arms and also rotating parts [3]. On the other hand, due to very stable and highly adherent layer of oxide [4], titanium alloy is applied in replacing various human body parts such as knee, dental implant elbow [5], heart valve [6]. In addition the strength of titanium alloy can be greatly increased by strain hardening process [7]. However application of the alloy is limited up to 450-600 o C [8] depend on the composition of the alloys. One of the most important characteristics of titanium alloy is its high affinity with oxygen that easily form titania (oxide layer) on the surface of the alloy [9]. This oxide layer formation can reach few atoms thicknesses (5-20atoms thickness) [10]. In addition to the inertness of passivve layer, its high strength to weight ratio and non magnetic characteristic, make this alloy becomes a good choice in the replacement of human bone [5].Other than corrosion resistance, passive layer also important in creating photocatalyst properties of titanium alloys, which has the ability to alter the light energy to higher level of energy and assist in some of the chemical processes [11, 12, 13]. For Advanced Materials Research Vol. 650 (2013) pp 12-17 © (2013) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMR.650.12 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 TTP, www.ttp.net. (ID: 180.73.16.221-04/01/13,10:04:08)