Filamet Inconel 718-34

Filamet™ by Inconel 718-34 from The Virtual Foundry (TVF) is an innovative filament made of 86% metal and the rest PLA. The Virtual Foundry is an American company made up of great experts in the molten metal sector, who have been working constantly since 2014 to improve and grow their range of filaments and accessories for  FDM metal 3D printing. Their products are aimed to solve and simplify problems through innovative metal materials for FDM 3D printers of any kind.

Image 1: Gear manufactured with Inconel 718. Source: Saphire

Inconel is the recognized brand of nickel-chrome based superalloys. These are alloys that stand out for their high resistance to corrosion, capable of working in the most extreme conditions. This is due to the fact that, when heated, a thin layer of oxide is formed which passes over the surface and protects it from chemical attack, while at the same time improving its surface hardness. In addition to its extraordinary resistance to corrosion, it has excellent resistance to high temperatures, being able to provide service in conditions where other metals such as aluminium or steel would suffer from creep.

Among the different types of Inconel, the 718 type stands out for its excellent weldability, a quality that facilitates its sintering. In addition, its high niobium and molybdenum content, together with aluminium and titanium, make it extremely hard and resistant to traction.

Some of the most demanding applications include the production of gas turbine blades, Formula 1 vehicle exhausts and aerospace reactor manifolds.

The Virtual Foundry has been the pioneer in developing metal filaments for 3D printing after many years of research and development. The great competitive advantage developed is that to obtain pure metal parts it is only necessary to print the part and sinter it in an oven. Other manufacturers who have tried to develop metal filaments need to do an additional process (prior to sintering in the furnace): debinding, a chemical process to separate the binder polymers from the metal. Therefore, it can be concluded that The Virtual Foundry is the pioneer and the benchmark in FDM metal 3D printing, obtaining a fairly simple process with results never seen before in the world of metal manufacturing.

Currently, a large list of industry sectors are using The Virtual Foundry's filaments: 3D printer manufacturers, biomedical innovation, jet engine development, radiation shielding, space exploration, nuclear energy, dental, artists or fashion design. A notable application is the manufacture of a hot water internally heated drill bit for drilling in Antarctica. With the copper Filamet™, a drill with an internal structure that is extremely difficult to machine or mould has been produced easily and at a low cost. Another noteworthy application is the printing of containers for radiation shielding, carried out with the tungsten Filamet™. This type of container is used to transport reactive medicines without having to resort to lead (toxic) containers. Thanks to the density of tungsten, 1.6 higher than lead, this filament is ideal to create any type of substitute part for those made of lead.

Filamet™ of Inconel 718 is a filament formed by a base metal and a biodegradable and ecological polymer (PLA). This material is free of exposed metal particles and volatile solvents that can be released during printing. Made up of 86% Inconel 718 and the rest PLA, this material is extremely easy to print, as its printing properties are similar to those of PLA, allowing any user of a 3D FDM printer to create parts with this filament, without the need to purchase expensive industrial metal FDM 3D printers.

With Filamet™ Inconel 718, properties similar to those possible with DMLS technology are achieved but with certain limitations. Due to the need to sinter the parts printed with this filament, where PLA is eliminated, the parts have porosity, loss of volume and no isotropy. The DMLS 3D printers manage to print totally solid parts (similar to casting), with great detail, layer heights of 0.02 mm and without the need for post-processing, the only disadvantage compared to the FDM 3D printing of Filamet™ being the cost of: material, manufacturing and the printers themselves.

Due to its high metal content (86%), it is necessary to place the filament inlet as close as possible to the extruder and use FilaWarmer, a heater through which the filament is introduced to eliminate its curvature and thus produce the least possible friction in the extruder and HotEnd. Once a piece is printed, it is necessary to carry out the sintering process, in an open environment or in a vacuum or inert environment, to eliminate the polymer (PLA), taking into account that the sintering values must be adjusted according to the geometry and model of the furnace. The product obtained is totally metallic, with the real properties of the metal such as electrical conductivity, post-processing by grinding and polishing or even joining by welding; but with a certain porosity and a reduction in volume due to the loss of PLA. To know more about the whole process of printing, sintering and post-processing you should visit the section "Tips for use".

Users who do not have a furnace with the necessary properties to sinter the printed pieces with copper Filamet™ and achieve the final properties of this metal, can contact us and we will evaluate its viability through our collaborators with the capacity to carry out the necessary post-processing to obtain the desired final result.