Unified Enterprise Modeling Technique and Taguchi Method to Study and Improve Metal- Non-metal Bonding Process

Abstract

Enhancement of productivity of any enterprise (production or service) is always desirable. Enterprise models grasp certain viewpoints about an enterprise, such as Financial, Business, Information and human views. For formal modelling of any manufacturing enterprise it is necessary to decompose (or breakdown) the system into well manageable system elements. Enterprise modelling can facilitate and provide assistance, like a model which looks into the system features and suggests alternative solutions and application states that strength the system to accommodate business changes including; its processes, information requirements and communication systems and the approach that its resources are arranged and utilize. Modelling techniques can help to analyze alternate solutions and help to determine new system configurations that best satisfy requirements change. CIMOSA enterprise modelling technique is used to model a manufacturing Enterprise. Using this technique, alternative solutions were studied to increase production rate of a composite shaft assembly which is used to move the control surfaces of wings of a light aircraft. It was found that chemical bonding of metal coupling and composite shaft is the most critical process and its curing process is most time consuming. The bond strength of the assembly is checked through ultrasonic testing. Experiments were designed (DOE) using Taguchi method to optimize curing parameters of epoxy adhesive for required degree of bond strength. In this research study, Dr. Taguchi's Orthogonal Array (OA) L9 (34) was deployed to find out the best suitable conditions. The aim of this study is to examine the best suitable process parameters which reduce curing time of adhesive without affecting the strength of bond. In this research study, the specimens of the Aluminium LY12CZ with epoxy adhesive were prepared. ASTM standard D 1002 ‗Test Method for Shear Strength of Adhesives‘ was used to evaluate the shear strength of epoxy adhesive. The software Minitab17.3 was applied to design Experiments according to OA L9 (34) and find the S/N Ratio. Main effect of each parameter was calculated. Analysis of Variance (ANOVA) has been carried out to examine which design factors considerably affect the responses. ii A total of nine experiments were executed with one repetition of each factor tolerances. The optimum process parameters Curing Temperature 78°C, Curing Time 8hrs, Torque 13Nm, Surface Roughness Ra 1μm are recommended. After this research study, the metal-nonmetal assembly which was used to cure at room temperature for 48 hours for required degree of bonding quality, is now being cured at 78°C for 8 hours for the same or even higher degree of bonding quality. As a result the production manager saves 40 hours for one aerospace assembly without compromising on quality.