Parameter Optimization of Debinding Injection Moulded Ti-6Al-4V Mix With Palm Stearin and Polyethylene M. I. Jamaludin 1,a , N. H. Mohamad Nor 1,b , N. A. A. Kasim 1,c , J.B. Saedon 1,d and N. Muhamad 2,e 1 Faculty of Mechanical Engineering, University Technology of MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia 2 Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia a ikhwanjamal@gmail.com, b norhafiez@yahoo.com, c nuratikah.ak@gmail.com, d juri41@yahoo.com, e hamidi@eng.ukm.my Keywords: Taguchi method, metal injection molding (MIM), Ti-6Al-4V, Palm stearin, solvent debinding process, thermal pyrolysis. Abstract. Debinding process of injection moulded Ti-6Al-4V feedstock was divided into two parts: solvent debinding process to eliminate palm stearin (PS) and thermal pyrolysis to eliminate polyethylene (PE). Solvent debinding process used heptane at optimum temperature, 60°C to remove PS binder completely as temperature is the only parameter that can be optimized. Thermal pyrolysis parameters for removal of PE binder from the injected 65vol% Ti-6Al-4V feedstock have been optimized by using Taguchi method. Heating rate, temperature and time were the selected factors during experiment to be applied in the L 9 (3 4 ) Taguchi orthogonal array (OA) to find the best set of parameters to produce highest density of brown part. Thermal pyrolysis process was done at optimum parameters: heating rate: 5°C/min; temperature: 510°C; and time: 90 minutes. Analysis of Variance (ANOVA) was employed to find the best signal to noise ratio (S/N) to express the contribution of the factors towards quality characteristic. Based on the results, heating rate has the greatest contribution (54.63%), followed by duration time of thermal pyrolysis (24.40%) and temperature (19.25%). Introduction Metal injection molding (MIM) has gotten an increasing attention as a low-cost production technique for small, precise and intricate part made in high volumes [1]. The technique involves mixing of metal powder with a binder, injection of the feedstock into a mold, debinding process to remove the binder and sintering as the last step to consolidate the product to its final density [2]. Recently, metal injection molding of Titanium (Ti-MIM) has a promising demand from the market especially in aerospace and biomedical field [3]. Formulation of a binder system has substantial influences on the success of MIM production [2]. Selection of binder system in production of Ti-MIM affects the presence of other elements to react on an as-sintered product rather than the condition during the experiment [4]. Moreover, titanium is a highly reactive metal that can easily be distorted by other elements that can cause oxidation [5]. Palm Stearin (PS) binder is a simple binder system introduced by Iriany et al. [6] to be substituted with multi-components conventional binder system. Fortunately, Malaysia has abundant of PS resources [7]. PS is an alternative binder system to overcome long debinding times drawbacks. Currently, only a few researchers study the effect of PS binder system towards MIM which mainly involves in production of steel. Omar et al. [8] and Setasuwon et al. [9] have studied the influence of PS binder to manufacture stainless steel products. In this study, injected Ti-6Al-4V feedstock that consists of PS and PE as the binder was used to investigate the optimization of debinding parameters during removal of binders. Debinding process of injected Ti-6Al-4V feedstock has two sessions: solvent debinding process and thermal pyrolysis process. Highest Applied Mechanics and Materials Vol. 660 (2014) pp 234-238 Submitted: 23.06.2014 © (2014) Trans Tech Publications, Switzerland Revised: 14.08.2014 doi:10.4028/www.scientific.net/AMM.660.234 Accepted: 14.08.2014 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: 202.58.86.23-24/09/14,03:57:07)