Six-Sigma in Machining Process Development

Design for six sigma (DFSS) is becoming a powerful methodology for design and process development. Its application to the design of machining process plans for Powertrain components manufacturing is discussed in this paper. Traditional computer-aided process planning will typically generate computer-numerical control (CNC) codes by converting cutter locations (toolpaths) to a control program for CNC-driven machines. The toolpath can be optimized for cost, time and quality by using DFSS method to emphasize the critical to satisfaction metrics. Cost, cycle time and quality are competing metrics controlled by complex characteristics that can best be induced from experimental or empirical data. DFSS have proven to be an important method for characterizing the critical to quality factors, as well as cost and time, from a robust understanding of factors that contribute to the requirements on the surface finish, burr size, tool life, chip length and so on. Authors: E.I. Agba, E. Exner, P. Akinyemi (Ford Motor Company)