Abrasive waterjet milling for aerospace applications.

Abstract

The diploma thesis deals with the statistical study of determining the optimal input process parameters for the implementation of mask-less milling on difficult-to-machine material - Stainless steel AISI 304 by Abrasive Waterjet technology. In this study, the effect of traverse speed, TS = 1000mm/min and 3000mm/min, abrasive flow rate, AFR = 100g/min and 200g/min, stand-off distance, SOD = 4mm and 15mm for the respective step-over distance, SD = 0.6mm and 0.7mm were studied on the output responses of width, depth, surface roughness parameters Ra and Rz. A total of 16 experiments using full factorial design classified under the two step-over distances were performed and the experimental results were analyzed using the Minitab software. The results demonstrated the maximum possible width is achieved by the execution of lower TS, higher AFR and higher SOD; the maximum possible depth is achieved by the execution of lower TS, higher AFR and lower SOD; and the minimum possible Ra and Rz is achieved by the execution of higher TS, higher AFR and lower SOD. By performing ‘desirability approach’ optimization, the optimum parameter configuration with respect to both step-over distance 0.6mm and 0.7mm was found with TS = 1000mm/min, AFR = 200g/min, and SOD = 4mm. The study concludes the utilization of multiple input variables within the experimental domain to achieve more accurate results as per the desired output requirements.