Analysis and optimization of surface quality while machining high strength aluminium alloy

[Display omitted] •Analysis and optimization of machinability of Al 7075 for aerospace application is presented.•Effect of machining parameters on form error and surface roughness is investigated.•Optimization is done for good surface quality and material removal rate.•Empirical models are developed for correlation of process parameters and machinability indicators.•Optimal turning parameters for ready industrial use are recommended for Al 7075. This paper presents a systematic investigation on analysis and optimization of surface quality during turning of high strength Al 7075. In this central composite design based study, the effect of four important machining parameters such as cutting speed, feed rate, depth of cut, and tool nose radius on the surface quality characteristics namely form error i.e. cylindricity error and circularity error, and average surface roughness has been investigated. The material removal rate is also considered as an important response parameter. The analysis of variance study has been conducted to find the statistically significant parameters. The derived empirical relationships predicted the randomly generated test cases with less than 8.51%. Optimization for multiple outputs with conflicting requirements has been done using the principal component analysis and JAYA algorithm that resulted in the absolute deviation of 7.97% with average roughness- 0.64 µm, circularity error- 4.34 µm, cylindricity error- 0.365 µm, and material removal rate-28.63 cm3/min.