Feasibility study on hybrid manufacturing – combining laser-based powder-bed fusion and chill casting on the example of EN AC-42000 alloy Machbarkeitsstudie zur hybriden Fertigung – Kombination von laserstrahlbasiertem Pulverbettschmelzen und Kokillenguss am Beispiel der Legierung ENAC-42000

Abstract

Laser-based powder-bed fusion can be combined with casting into a hybrid manufacturing process. This is done to simultaneously utilize advantages of both processes. To examine related challenges stemming from this combination when using aluminium alloys, first experiments were conducted with EN AC-42000 alloy, an alloy common in both standalone processes. EN AC-42000 alloy samples with different surface treatments were placed into a sand mould and cast on to with an aluminium melt. The contact region between the partially molten insert and the cast material was examined with light microscopy. The main challenges were shown to be comprised of bonding issues due to present oxides and a high porosity. The high porosity was traced back to a porosity increase in the laser-based powder-bed fusion insert.