A study of machining net-shape metallic components obtained by selective laser melting (SLM)

Abstract

Manufacturing presents growing challenges brought by the discovery of new materials, new manufacturing processes and innovative applications of both. Portable devices and implants, for example, made of Al and Ti alloys, are high added value goods with high quality components offered to a global market. The development of such industry in any modern society will very much depend upon its ability to overcome constant challenges, which will demand higher volume of research and capable human resources. The more advanced manufacturing processes are common to aerospace and defense industries but rapidly must become available to a larger variety of industries creating new opportunities within the global market. One of the most recent and innovative technologies consists in obtaining metallic parts close to their final dimensions (net shape) by the addition of material in layers. By doing so, costs and energy are minimum, requiring only finishing operations using subtractive processes, such as machining. The present proposal aims at a contribution to overcome the challenges imposed to manufacturing, focusing on the Selective Laser Melting (SLM), one of the most recent developed Additive Manufacturing processes (AM). The present research proposes to study the machining operations of workpieces obtained by such ´processes using theoretical and experimentally techniques. Since workpices are produced in net shapes with reduced stock material, cutting edge geometries become fundamental, as well as cutting forces and chip formation. Those parameters are the most important ones for the success of finishing operations by machining. Surface finishing and its integrity as a function of cutting conditions are one of the targets of the present investigation, since obtaining the workpiece by SLM is just the first part of the manufacturing chain, followed by machining operations as the finishing process. The machining operation and its performance applied to workpieces obtained by SLM will be compared to drawn material, which is the conventional and more commonly used one. (AU)