The Effect of Cutting Parameters on Surface Quality and Corrosion Resistance of Micro-machined Surfaces of 7075 Aluminum Alloy

The objective of this study is to investigate the impact of cutting parameters on the corrosion resistance of micro-machined surfaces. Through a single-factor micro-cutting experiment and utilizing the CHI660E electrochemical workstation, the influence of different cutting parameters on cutting force, surface roughness, and corrosion resistance of machined surfaces of 7075 aluminum alloy is explored. The findings reveal that, when considering the same cutting parameters, higher cutting speeds result in lower surface quality compared to lower cutting speeds. The minimum surface roughness (Ra) value obtained is 0.187 & mu;m, while the minimum corrosion current density for the sample with a cutting speed of 200 mm/s is 2.711 x 10-6 A cm-2, accompanied by the least amount of corrosion products on the machined surface. The cutting force demonstrates an almost linear increase with the growth of cutting depth, with the maximum cutting force recorded at 21.6N. Cutting depth proves to be the primary factor affecting workpiece surface roughness, with greater cutting depths resulting in higher surface roughness values, reaching a maximum of 0.327 & mu;m (Ra). As the cutting depth increases from 20 to 40 & mu;m, the self-corrosion potential of the samples shifts negatively by 22 mV, leading to a gradual weakening of their corrosion resistance. In terms of the feed rate, as it increases from 1.25 to 11.25 & mu;m/z, the self-corrosion potential moves forward by 30 mV, resulting in a 51.2% decrease in current density and an overall enhancement in corrosion resistance. The optimal combination of cutting parameters determined from this study is a cutting speed of 200 mm/s, cutting depth of 20 & mu;m, and feed rate of 3.75 & mu;m/z. These findings provide valuable insights into the relationship between cutting parameters, surface quality, and corrosion resistance, aiding in the optimization of micro-machining processes for 7075 aluminum alloy.