8 ms·
> First the basalt is melted at a temperature of 1,400 °C (2550 °F). The molten rock is then extruded through small nozzles for the production of filaments of b
by Xmd5a 11mo ago
> First the basalt is melted at a temperature of 1,400 °C (2550 °F). The molten rock is then extruded through small nozzles for the production of filaments of basalt fibers.
As a 3D-printer user, I flinched.
- endymion-light 11mo agocouldn't imagine what the spaghetti looks like
- Gravityloss 11mo agoOne could probably add some other minerals to lower the melting temperature. Like is done for regular glass. I am not a chemist but I would assume most likely still way too high for plastic-like temperatures.
- jaggederest 11mo agoAs a ceramicist it'd be difficult to 3d print with because the kinds of temperatures you can reach even with heavily fluxed silica is still extremely high. I fire bisque at cone 04 which is approximately 1060C / 1940F and that's considered low fire, only extremely heavily fluxed glazes (usually pure frit or equivalent) melt at that level. Putting 3d printing concepts on the table, though, you could definitely see something like a sintered bed printer using a laser to print it, but then you wouldn't get anything close to the standard FDM style print.
- Gravityloss 11mo agoI also assume directional solidification is really important for basalt, like for glass fibers and others. That's hard to achieve for bulk objects but easy for fibers.
- positron26 11mo agoFundamentally, if the nozzle temperatures can't possibly withstand what they are extruding without eroding, we can either: - balance an exothermic reaction (self-propagating high-temperature synthesis) to occur just after leaving the nozzle - externally apply the heat with laser or plasma arc etc The limit of externally applying heating is when the heat flux has to be so high that some material vaporizes and pops. An exothermic reaction within the material overcomes this limitation.
- jaggederest 11mo agoThe other alternative is like current state of the art 3d printing ceramics - you either replace some high percentage of the filament with clay and fire it as a post processing step and it burns off the plastic, or print a clay/water slurry directly and fire it after drying. But I don't think we'd end up with the basalt being very filamentous.
- positron26 11mo agoIf the binder that gives you something printable at low temperature doesn't integrate into the final result through chemical reaction, you are almost assuredly going to get a high porosity mess where the binder had to vaporize out. If instead the binder and precursor can melt, react, and expand into a solid that precipitates out because of a super high melting point, the expansion will ensure that you get a fully dense part that can be machined back down.
- kragen 11mo agoFelsic lavas can melt at 750° and even below, and prehistoric terra cotta ceramic is often fired at such low temperatures. That's still quite a bit cozier than nylon or PET, of course.
- kragen 11mo agoYes, you could convert the basalt into glass. But basalt fibers have some real advantages over glass fibers, mentioned in the linked page: > Basalt Woven Textile has high corrosive and chemical resistance to the influence of a corrosive media: salt solutions, acid solutions and particularly alkali liquids. The specific strength of basalt fiber exceeds the strength of alloyed steel by a factor of 2,5 and the strength of glass fiber by a factor of 1,5. Heat-insulating items made from basalt fiber combined with inorganic binding agents may be used by temperatures up to 700°С. In addition there is a range of compositions consisting of basalt rocks that have a higher thermal stability – up to 800°С.