Rapid prototyping (RP) has evolved as frontier technology in the recent times, which allows direct transformation of CAD files into functional prototypes where it tremendously reduces the lead time to produce physical prototypes necessary for design verification, fit, and functional analysis by generating the prototypes directly from the CAD data. Part quality in the rapid prototyping process is a function of build parameters such as hatch cure depth, layer thickness, orientation, and hatch spacing. Thus an attempt was made to identify, study, and optimize the process parameters governing the system which are related to part characteristics using Taguchi experimental design techniques quality. The part characteristics can be divided into physical part and mechanical part characteristics. The physical characteristics are surface finish, dimensional accuracy, distortion, layer thickness, hatch cure, and hatch file, whereas mechanical characteristics are flexural strength, ultimate tensile strength, and impact strength. Thus, this paper proposes to characterize the influence of the physical build parameters over the part quality. An L9 orthogonal array was designed with the minimum number of experimental runs with desired parameter settings and also by analysis tools such as ANOVA (analysis of variance). Establishment of experimentally verified correlations between the physical part characteristics and mechanical part characteristics to obtain an optimal process parameter level for betterment of part quality is obtained. The process model obtained by the empirical relation can be used to determine the strength of the prototype for the given set of parameters that shows the dependency of strength, which are essential for designers and RP machine users. 1. Introduction Due to the advances in electronics and computers, there has been a significant growth in communication, information technology, and worldwide networking, which leads to globalization and opening of markets [1, 2]. Thus in product development, rapid prototyping (RP) and rapid product development have turned out to be the key instruments to save time and money with respect to the development of innovative products [2, 3]. Stereolithography (SLA) is one of the RP techniques, which involve fabrication of intricate shape of a plastic monomer directly from computer aided design (CAD) data by depositing material layer by layer by photopolymerization process . The SLA process involves the following steps: conversion of the CAD model to the standard triangulation language (STL) file format; slicing
T. Luangvaranunt, C. Dhadsanadhep, J. Umeda, E. Nisaratanaporn, and K. Kondoh, “Aluminum-4 mass % Copper/Alumina composites produced from Aluminum Copper and rice husk ash silica powders by powder forging,” Materials Transactions, vol. 51, no. 4, pp. 756–761, 2010.
S. Dingal, T. R. Pradhan, S. Sundar, C. A. Roy, and S. K. Roy, “Experimental investigation of selective laser sintering of iron powder by application of Taguchi method,” in Proceedings of the Laser Assisted Net Shape Engineering conference (LANE '04), pp. 445–456, Erlangen, Germany, 2004.
S. Guharaja, A. Noorul Haq, and K. M. Karuppannan, “Optimization of green sand casting process parameters by using Taguchi's method,” International Journal of Advanced Manufacturing Technology, vol. 30, no. 11-12, pp. 1040–1048, 2006.
S. R. Rao and G. Padmanabhan, “Application of Taguchi methods and ANOVA in optimization of process parameters for metal removal rate in electrochemical machining of Al/5%SiC composites,” International Journal of Engineering Research and Applications, vol. 2, no. 3, pp. 192–197, 2012.
M. Nataraj, V. P. Arunachalam, and G. Ranganathan, “Using risk analysis and Taguchi's method to find optimal conditions of design parameters: a case study,” International Journal of Advanced Manufacturing Technology, vol. 27, no. 5-6, pp. 445–454, 2006.
S. O. Onuh and K. K. B. Hon, “Application of the Taguchi method and new hatch styles for quality improvement in stereolithography,” Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, vol. 212, no. 6, pp. 461–472, 1998.
J. G. Zhou, D. Herscovici, and C. C. Chen, “Parametric process optimization to improve the accuracy of rapid prototyped stereolithography parts,” International Journal of Machine Tools and Manufacture, vol. 40, no. 3, pp. 363–379, 2000.
W. H. Yang and Y. S. Tarng, “Design optimization of cutting parameters for turning operations based on the Taguchi method,” Journal of Materials Processing Technology, vol. 84, no. 1–3, pp. 122–129, 1998.
N. Tosun, C. Cogun, and G. Tosun, “A study on kerf and material removal rate in wire electrical discharge machining based on Taguchi method,” Journal of Materials Processing Technology, vol. 152, no. 3, pp. 316–322, 2004.
J. A. Ghani, I. A. Choudhury, and H. H. Hassan, “Application of Taguchi method in the optimization of end milling parameters,” Journal of Materials Processing Technology, vol. 145, no. 1, pp. 84–92, 2004.
K. Chockalingam, N. Jawahar, U. Chandrasekar, and K. N. Ramanathan, “Establishment of process model for part strength in stereolithography,” Journal of Materials Processing Technology, vol. 208, no. 1–3, pp. 348–365, 2008.
C. C. Wang, T.-W. Lin, and S.-S. Hu, “Optimizing the rapid prototyping process by integrating the Taguchi method with the Gray relational analysis,” Rapid Prototyping Journal, vol. 13, no. 5, pp. 304–315, 2007.