Metal Additive Manufacturing Conference 2018

Fused Filament Fabrication (FFF) is a type of material extrusion (ME) additive manufacturing and it is one of the most commonly used polymer-based additive manufacturing techniques. FFF can be used to shape parts with feedstocks similar to the ones used in Powder Injection Moulding (PIM). Thus green parts are manufactured which in the following steps are debinded and sintered. This process requires mostly the feedstocks in the shape of a filament, which is required for printing. The use of filaments as feeding material imposes a set of requirements on the feedstocks, such as the flexibility to be spooled, stiffness to avoid buckling and a constant diameter to ensure a constant mass flow. FFF for metals parts offers the use of a wide range of metal powders, which are already available in the market, as well as an already established process of sintering which leads to homogenous microstructure. Here an overview of the state-of-the-art of FFF for metal parts with regard to the powders, feedstocks as well as available equipment, respective processing parameters and examples for currently achieved sinter shrinkage; densities and other mechanical properties as well as achievable surface quality are given.