Filamet high carbon iron

Filamet™ high carbon iron from The Virtual Foundry (TVF) is an innovative filament composed of more than 75 % metal and the rest by PLA that can be sintered. The Virtual Foundry is an American company formed by great experts in the sector of molten metal, which have been constantly working since 2014 to improve and grow its range of filaments and accessories for 3D FDM metal printing. Its products are oriented to solve and simplify problems through innovative metallic materials for 3D FDM printers of any kind.

Image 1: Gear made of high carbon iron without sintering. Source: The Virtual Foundry

The high carbon iron is an alloy formed by iron and a percentage of carbon, up to 2 %, which gives it hardness and high strength, sacrificing typical advantages of steel, such as ease of welding. Carbon iron are thus designated to differentiate them from stainless steels and alloy steels. Steel is a metal used in an infinite number of applications thanks to its ease of obtaining the raw material, easy processing and great knowledge of alloy and forming. This is reflected in the fact that any type of industry is committed to manufacturing its products with steel, especially those components exposed to great mechanical stress. To obtain steels with high carbon content, it is necessary to subject the steel to a heat treatment to achieve 0.3 % to 1.7 % by weight of carbon. This process is delicate due to the appearance of impurities that reduce the quality of steel, being necessary to allocate the metal with other elements. Although it seems like a complex and unproductive process, high carbon steel is indispensable for the manufacture of necessary products at industrial and domestic level: cores of electromagnets, tools, cutting objects, springs, high resistance wires, etc.

Filamet™ high carbon iron is a highly ferromagnetic filament, in equal measure before and after being sintered. This quality can be used to manufacture parts to which magnets must adhere or as a core of electromagnets.

The Virtual Foundry has been the pioneer in developing metallic filaments for 3D printing after many years of research and development. The great competitive advantage developed is that to obtain the pure metal parts it is only necessary to print the piece and sinter it in an oven. Other manufacturers that have tried to develop metallic filaments need to do one more process (prior to sintering in the furnace) which is the debinding that consists of 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 3D metal FDM printing, obtaining a fairly simple process with results never seen so far in the world of metal fabrication.

Currently, a large list of industry sectors are using The Virtual Foundry filaments: 3D printer manufacturers, biomedical innovation, jet engine development, radiation shielding, space exploration, nuclear energy, dental, artists or fashion design. A remarkable application is the manufacture of a drill with internal hot water heating, for drilling in the Antarctic. With the Filamet™ copper it has been manufactured, very easily and at a low cost, a drill with an internal structure extremely difficult to machine or mold has been manufactured very easily and at a low cost. Another notable application is the printing of containers for radiation shielding with tungsten Filamet™. These types of containers are used to transport reactive medicines without having to resort to lead containers (toxic). Thanks to the density of tungsten, 1.6 higher than lead, this filament is ideal for creating any type of replacement part made from lead.

Filamet™ high carbon iron is a filament, which can be sintered, formed by 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. Formed by more than 75 % high carbon iron and the rest by PLA, this material is extremely simple to print, since its printing properties are similar to those of the PLA, which allows any user of a FDM 3D printer create parts with this filament, without the need to buy expensive industrial 3D FDM metal printers. With Filamet™ 316L properties similar to those possible with DMLS technology are achieved but with certain limitations. Due to the need to sinter the printed pieces with this filament, where the PLA is removed, the pieces have porosity, loss of volume and non-isotropy. DMLS 3D printers manage to print totally solid parts (similar to the foundry), in great detail, layer heights of 0.02 mm and without the need for post-processing, the only disadvantage compared to Filamet™ 3D FDM printing the cost of: material, manufacturing and the printers themselves.

Image 2: Model manufactured with Filamet™ high carbon iron and sintered. Source: The Virtual Foundry

Due to its large metal content (78 %), it is necessary to place the filament inlet as aligned as possible with the extruder. 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 sintering values must be adjusted depending on the geometry and oven model. The product that is obtained is totally metallic, with the real properties of the metal as electrical conductivity, post-processed by sanding and polishing or even welding union; 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 "Tips for Use" section.

Image 3: Cones made of no sintered and sintered high carbon iron Filamet™. Source: The Virtual Foundry

Users who do not have an kiln with the necessary properties to sinter the printed parts with the Filamet™ high carbon iron and get the final properties of this metal, can contact us and we will assess its viability through our collaborators with ability to perform the post-processing necessary to obtain the desired final result.