Investigations on surface roughness and microhardness of turned AM alloy

Manufacturers in different sectors look for materials exhibiting good mechanical properties, high machinability, and superior surface integrity. The machinability of Mg alloys is one of the vital aspects which requires an exhaustive survey during their selection for different applications. The study examines the surface integrity of a fabricated AM alloy (Mg alloy with 7 wt%Al-0.9 wt%Mn) through dry turning. During the experiments, the input variables of turning viz. cutting speed(v), depth of cut (DOC), and feed(f) is altered and applied to the workpiece. The data obtained for the two response variables viz. surface roughness and microhardness accentuate the maximum influence of feed, followed by DOC and speed. For validation a two-stage methodology was adopted; In the first stage, the validation was done with the help of Analysis of variance (ANOVA); the results show the % contribution of feed, speed, and DOC on average roughness is 66.94%, 5.91%, and 27.23% and on microhardness is 47%, 8.3%, and 44.57%, respectively. Subsequently, in the second stage, the surface plots are drawn for both the response variables to ascertain the ANOVA outcomes; the shape of the plots corroborates the experimental and ANOVA results. The study results provide vital insights for parameter selection to get improved results on surface roughness and microhardness during machining of AM alloy.