Quality and productivity trade-off in powder-bed additive manufacturing

Abstract

Additive manufacturing (AM) is a technology that creates parts directly from 3D CAD files based on a layer-by-layer manufacturing process. Quality and productivity are the two key concerns in powder-bed AM processes, which are one of the most widely used AM in the industry. Because of the keyholes and porosity formation occurring in the object’s structure during a printing process, quality is considered a difficult factor to manage. On the other side, focusing only improving quality could result in higher building cost and inefficient printing operations. Thus, a trade-off between these two concerns is vital for maintaining competitiveness of AM. To the best of our knowledge, there is no study in the literature that has yet considered this trade-off in a systematic way and can provide optimal results for productivity based on a desired quality level. This study combined equations from previous studies in a systematic way to create an empirical model to optimize major process parameters, including laser power, scan speed, layer thickness, hatch distance, and laser spot size for a trade-off between quality and productivity in powder-bed AM processes. The combined and individual effects of all process parameters were analyzed in a numerical experiment to show their significance for the printing process. The case study also showed that the proposed empirical optimization model yielded lower building costs than those from similar studies in the literature and is effective on maximizing productivity at the desired quality level.