Development and Characterization of Bound Metal Deposition Including Laser Ablation

Abstract

Bound Metal Deposition (BMD) is a novel metal additive manufacturing technology in which a metal powder-binder composite paste is layer-wise extruded to form a part, which is then debound and sintered into a solid metal part. Although promising, BMD suffers from shrinkage-induced warpage and an inability to produce fine length scale features. This research addresses these problems by: (1) characterizing warpage of planar parts, and (2) developing a novel laser ablated process to create fine length scale features. First, a 12-factor resolution IV fractional-factorial design of experiments (DOE) was conducted to determine the warpage of planar parts as a function of part geometry, infill density, and process conditions. Results indicate part height and length were most influential for as-sintered warpage. Second, a novel laser ablation BMD (laBMD) process was developed and characterized via a full-factorial DOE. Factors included pattern geometry and process parameters. Results show the as-sintered ablation depth, ablated surface roughness, and angle between ablated and non-ablated regions were tailorable via processing parameters. The results from the laBMD DOE were applied to the design of a microfluidics mold for roll-to-roll forming