Net shape forming of green alumina via CNC machining using diamond embedded tool

Diamond embedded tools were fabricated through nickel electroplating of mild steel conical shaped shank for machining of green alumina compacts using Computer Numerical Control (CNC) machine. Flat and pointed end conical tools embedded with different grain sizes viz. similar to 117 mu m (120 mesh) and similar to 20 mu m (625 mesh) of diamond particles were used for green machining of alumina. The hardness values of 625 and 120 mesh tools were measured to be 13.79 +/- 3 GPa and 11.84 +/- 6 GPa, respectively. Diamond embedded tools were successfully used for net shape fabrication of symmetrical and unsymmetrical objects such as cylinder, dental crown, 3D pattern via CNC machining with submicron range surface roughness. Analysis of mechanical properties and Weibull modulus of the green and sintered alumina samples after green state machining revealed that net shape forming via green machining of alnmina using diamond embedded tool is viable. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.