Micro-milling cutting conditions influence on part geometrical accuracy, surface quality and tool wear in Ti-Grade-5 alloy

Abstract This work focuses on analyzing the consequences of micro-milling process variables on part geometrical accuracy, area surface finish (S a ) and tool wear. Ti-Grade-5 (Ti-6Al-4V) was selected as the work material due to its established applications in biomedical micro parts and its potential for performance improvement. A tungsten carbide flat end two flute micro-milling cutter with a diameter of 500 μm was chosen as the cutting tool. A feed rate (f z ) range of 0.2–0.3 μm tooth −1 was selected for the work material, taking into account the size effect. Other variables included a depth of cut (a c ) ranging from 75 to 150 μm and cutting speed (v c ) ranging from 23.55 to 70.65 m min −1 . Taguchi L 9 Orthogonal array-based micro-milling experiments were conducted using a unique micro-cutting tool. The response variables measured included tool wear, geometrical accuracy, and S a values.The results indicate that operating at lower ranges of v c (23.55 m min −1 ), f z (0.2 μm tooth −1 ), and a c (75 μm) yields a geometrical accuracy of 33.334 μm, an S a value of 0.185 μm, and minimal tool wear of 11 μm. It was observed that under these lower operating conditions, there is an increased time interval for material removal and reduced contact between the workpiece and the tool. In conclusion, optimizing cutting conditions based on the size effect will enhance part geometrical accuracy, surface finish, and tool performance during the micro-part generation process in Ti Grade-5 alloy.