This study provides an in-depth investigation into low-cost and no-cost substrate release mechanisms that allow gas metal arc weld 3-D printed ER4043 aluminum and ER70S-6 steel parts to be removed from a reusable print substrate with minimal energy. Aluminum oxide, boron nitride, and titanium nitride coatings were evaluated as possible substrate release agents for aluminum printing. Additionally, the in situ formation of substrate release agents such as intermetallics and oxides were tested for both aluminum and steel printing. Testing was performed with a modified Charpy impact tester to remove 3-D printed metal parts from an 1100 aluminum or A36 low carbon steel print substrate to assess the impact energy required for removal. Specimen porosity was measured prior to sectioning and microstructural analysis, hardness traverses were measured across the specimens, and the elastic and shear moduli of the parts were analyzed via ultrasonic methods. All of the employed substrate release mechanisms minimized weld penetration and, in some instances, formed a brittle phase with the print substrate that allowed the specimens to be removed with minimal impact energy. These results thus provide methods with the removal of metal 3-D printed parts from print substrates with no specialized tooling or equipment conducive to distributed manufacturing.
A.S. Haselhuhn, B. Wijnen, G. C. Anzalone, P. G. Sanders, J. M. Pearce, In Situ Formation of Substrate Release Mechanisms for Gas Metal Arc Weld Metal 3-D Printing. Journal of Materials Processing Technology. 226, pp. 50–59 (2015). http://digitalcommons.mtu.edu/materials_fp/57