On Monday, January 6th, we will remain closed due to a holiday. Orders received from Friday, January 3rd at 5:00 PM (GMT+1) will be shipped on Tuesday, January 7th. |
-
Menu
-
<
3D PRINTERS
-
-
<
3D scanners
-
-
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
-
<
FILAMENTS
-
-
-
-
-
-
Buscador de propiedades
-
-
-
<
RESINS
-
-
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
-
<
POWDERS
-
-
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
-
<
Pellets
-
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
-
<
ACCESSORIES
-
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
-
<
DIY
-
-
-
-
Buscador de propiedades
-
-
-
Buscador de propiedades
-
-
- < Blog
- < Blog
- < Brands
- < Glossary
Steel Mix Refractory Powder is a powder developed for use in the sintering process of 3D printed parts with The Virtual Foundry's Filamet™ metal filaments, such as 316L filament, Inconel filament or 17-4 filament.
These metal filaments are composed of a high percentage of metal particles (80-95%) and PLA, which acts as a binder for the metal powder. Thanks to the PLA content, these filaments can be used in almost any FDM 3D printer on the market using the same printing parameters as with standard PLA. It should be noted that the high metal particle content of these materials does affect the brittleness of the filament, and it is recommended to use Filawarmer to optimise the printing process with these filaments by reducing the risk of breakage.
In order to achieve all-metal parts with these filaments, the 3D printed parts must undergo a sintering process to remove the binder material (PLA).
To carry out the sintering process of 3D printed parts with 316L, Inconel and 17-4 filaments, the following steps must be followed:
- Fill a crucible with refractory powder of steel mix.
- Insert and bury the 3D printed part.
- The user should leave about 40 mm of free space at the top of the crucible, which should be filled with sintering carbon.
Image 1: Sintering process. Source: The Virtual Foundry
The product obtained after sintering is a fully metallic part, with the real properties of the metal, such as post-processing by sanding and polishing, or even welding; but with some porosity and a reduction in volume due to the loss of PLA.
For sintering metal filaments such as 316L, Inconel or 17-4, a vacuum or inert furnace must be used. The table below shows the recommended sintering materials for each of The Virtual Foundry's Filamet metal filaments:
Bronze | Copper | 316L | Inconel | 17-4 | |
---|---|---|---|---|---|
Alumina Crucible | |||||
Crucible Graphite | |||||
Crucible Stainless steel | |||||
Refractory powder |
Al2O3 + Sintering carbon |
Al2O3 + Sintering carbon |
Steel mix powder + Sintering carbon |
Steel mix powder + Sintering carbon |
Steel mix powder + Sintering carbon |
Max. temp. Sintering | 871 ºC | 1074 ºC | 1260 ºC | 1260 ºC | 1232 ºC |
Table 1: Products for TVF metal filament sintering. Source: The Virtual Foundry.
To learn more about the whole sintering process you should visit the "Tips for Use" section.
General information |
|
Manufacturer | The Virtual Foundry |
Quantity | 1 kg |
Other |
|
HS Code | 2818.2 |
Post-processing: Sintering in a vacuum or inert furnace
The sintering of Filamet metal filaments must be carried out in a vacuum or inert environment furnace, a crucible (firing vessel) and refractory steel mix powder are required. The steps to be followed are as follows:
- First, prepare the workpiece for sintering by placing it inside the crucible and covering it with refractory powder, taking into account that there should be at least 10 mm of powder between the surfaces of the workpiece and the crucible.
- The user should leave approximately 40 mm free at the top of the crucible, which should be filled with coconut charcoal for sintering.
- The crucible is then placed in the furnace at room temperature. The temperature is increased to the corresponding sintering temperature (see table) and held for a certain time. Finally, the furnace should be allowed to cool down to room temperature.
Material | Temperature |
---|---|
Filamet™ 316L stainless steel | 1260 ºC |
Filamet™ Inconel 718-34 | 1260 ºC |
Filamet™ acero 17-4 | 1232 ºC |
Table 1: Temperature and time of the last sintering step as a function of the material type
The mechanical properties of the final product are directly related to the time the printed part is kept at the sintering temperature. If the final product is powdery and brittle, the sintering time has not been long enough. If the print shows a wrinkled leather-like surface, it is over-sintered. Finally, as a general rule, during the sintering process, the volume of the piece is reduced by approximately 7%.
Post-processing: Sanding and polishing
Once the workpiece has been sintered, it can be sanded and polished in the same way as metal, but following a series of instructions. With water sandpaper, print lines and other small deformations can be removed because the particles released during sanding adhere to the gaps due to the heat of friction. When using 3M sandpaper or 3M radial discs, it is recommended to start sanding with a grit of 120 (80 for 3M radial discs), taking care not to deform the most delicate areas, such as corners. Once the entire surface has been sanded, use the next grit and so on up to 6 or 7 grit (4 times for the 3M radial disc).
Before proceeding to the final polishing, it is recommended to use 3000 grit sandpaper to achieve a certain shine. Finally, once the part has been cleaned with a flannel cloth, the part can be polished. TVF recommends using a rotary tool with a polishing disc and polishing wax to make polishing faster and more effective. Simply apply a little polishing wax to the polishing disc and polish with constant movements all over the workpiece so as not to generate excess heat, which can deform the workpiece.
In addition to grinding and polishing, parts made with Filamet™ can be carved, remelted, welded and smoothed with the application of heat depending on the filament used.
The Virtual Foundry offers more information about Filamet filament sintering at the following link.