Ceramic Machining Evaluation

The U.S. Army Research, Development and Engineering Commands RDECOM Aviation and Missile Research Development and Engineering Centers AMRDEC Manufacturing Science and Technology Division MST at Redstone Arsenal, Alabama, is engaged in a Ceramic Manufacturing Technology Program CMTP. The objective of this effort is to assess current and newly developed ceramic machining technologies and to perform initial evaluation of various machining parameters and tooling. The light weight of ceramic materials and their outstanding resistance to wear and high temperatures make them increasingly preferred for industrial applications. However, machining ceramics is very costly and time consuming. Grinding, with its high cost and low volume material removal rate MRR, is still the most common method used to finish machine sintered fired ceramic components. New machining methods must be evaluated to produce ceramic components in a more timely, cost-effective manner. The accompanying table of NCDMM test results shows that machining ceramic material in the presintered bisque state using Polycrystalline Diamond PCD tools produced a higher MRR up to 250 or 1000 times greater if compared to grinding, depending on endmill size used than machining sintered ceramics using other methods. Therefore, to minimize the time and cost associated with finish machining after sintering, ceramic materials should be machined in the bisque state with PCD tooling whenever possible.