Modelling and Optimisation of Resilience and Corrosion Rate of Aluminium 7075 Thin Plate during Surface Grinding

Abstract

The main goal of this work is to model and optimise the resilience 
and corrosion rate of Aluminium 7075 (AA7075) thin plate during 
surface grinding. AA7075 thin plates were ground with respect to 
the factorial design schedule, and their resilience and corrosion 
rate were determined from the DI-CP/V2 servo-hydraulic testing 
machine and the CS series electrochemical workstation, 
respectively. The Minitab statistical tool was utilised to analyse 
the data. Statistical analysis revealed that feed rate (absolute 
standardised effect = 8.68) and table speed (6.81) are the most 
influential factors affecting resilience, while the feed–grinding 
depth interaction (2.78) also contributes significantly. The 
interactions between table speed and feed, and between table 
speed and grinding depth, were not significant. For corrosion 
rate, feed and its interaction with grinding depth exhibited the 
strongest influence (10.94), followed by table speed (6.37) and 
the three-factor interaction (2.34), whereas other interactions 
were insignificant. The resilience model demonstrated good 
predictive capability (R² = 83.64%, adj. R² = 75.22%, pred. R² = 
61.05%), while the corrosion rate model showed excellent 
predictive accuracy (R² = 99.20%, adj. R² = 98.42%, pred. R² = 
96.78%). The optimal conditions were found to be low table 
speed (2.0 spm), low feed (1.0 mm), and moderate grinding depth 
(0.5 mm) with a composite desirability of 0.817.