Multi-Response Optimization of Process Parameters for MIG Welding of AA2219-T87 by Taguchi Grey Relational Analysis

Aluminium alloy AA2219 is a high strength alloy belonging to 2000 series. It has been widely used for aerospace applications, especially for construction of cryogenic fuel tanks in missiles. However, MIG welding of AA2219 material is very critical. So selection of proper process parameters plays a major role in determining the quality of the weld joint. This study focuses on the optimization of process parameters for MIG welding of the material AA219-T87 using Taguchi based grey relational analysis. The welding input parameters play a vital role in optimized desired weld quality. The input parameter chosen were the welding current, Voltage and welding speed. The experiments were conducted according to L-9 orthogonal array. AN0VA method was used to assess the significance of factors on the best quality of the weldment. ANOVA results indicated that welding current played a major role on the quality targets (Transverse shrinkage, ultimate tensile strength and hardness) of the weldments followed by welding speed and voltage. Grey relational analysis was applied to optimize the input parameters simultaneously considering multiple output variables. Metallurgical aspects of the weld with highest and lowest grey relational grade was also discussed. (c) 2017 Elsevier Ltd. All rights reserved.