Materials can be functionalized by strategically incorporating fillers or modifiers to a formulation. For example, adding carbon nanotubes improves the electrical conductivity of a material, making it suitable for applications in electronics. Similarly, the inclusion of ceramics with high thermal conductivity enhances the part’s ability to dissipate heat. By carefully adding other fillers, the range of applications for VLM materials is endless.
Ceramics are typically characterized by its high hardness, wear and temperature resistance, and compression strength. Also, they are also known for their electrical and thermal insulating capabilities, as well as resistance to corrosion and chemical attack. For these reasons, ceramics are widely used in various industries, from electronics or aerospace to oil & gas.
All sorts of metal powders can be processed, from steel to titanium or copper. The inorganic fraction is higher than in any other photopolymerization or extrusion system, leading to a denser final part, and more predictable post processing.
The incorporation of fiber loads in resin materials dramatically increases the viscosity, making it impossible for any AM systems. Supernova takes advantage of it, reinforcing bringing technical materials to the next level.
As a result, materials get enhanced mechanical properties by reinforcing the matrix, increasing strength, and stiffness.
Why does viscosity matter?
Low-viscosity resins can’t meet industrial standards and homologations due to the limited ingredient set available to keep viscosity within the processability range. Therefore, legacy formulations are predominantly formed by monomers and a very small fraction of oligomers, additives, fillers and modifiers can be used since its inclusion spikes viscosity out of the processing window. Consequently, low-viscosity resins will inevitably have compromised mechanical, thermal and chemical and performance.
During photopolymerization, monomers and oligomers bond covalently at their terminations, forming a matrix that is crucial for the final material properties. As low-viscosity resins are mostly formed by short-chain monomers, the are many more covalent bonds in the matrix, and it becomes inevitably over-crosslinked, leading to brittle parts that are prone to crack propagation from weakened bonds at functional termination, and inferior elastomeric behavior because of poor tear strength or elongation at break.
Some AM processes rely on heating up the material to lower its viscosity and enable its processing, but this has several drawbacks: The material undergoes curing reactions when exposed to heat, leading to inconsistent properties among layers as the last ones are affected by partial curing during a longer pre-heating period. Moreover, heat increases the VOC emissions, which pose serious health risks and require expensive equipment in the facilities to ensure a safe work environment.