Selective Laser Sintering (SLS) is widely used in additive manufacturing for polymers and, in modified forms, for metals and ceramics. Conventional SLS and laser melting routes can, however, impose thermal, material and process limitations, particularly when working with non-standard, fragile or highly functional powders.
3Dresyns has developed binder-based powder systems for alternative SLS processing routes based on Cold Metal Fusion (CMF), Cold Ceramic Fusion (CCF) and Cold Exotic Powders Fusion (CEPF).
These approaches enable direct, mold-free additive manufacturing of ceramic, metal, polymer and exotic powder systems without relying on complete laser melting during the printing stage.
From conventional SLS to Cold Fusion technologies
In conventional SLS and laser-based metal additive manufacturing, processing may involve:
- Partial or complete thermal fusion of powders using laser energy.
- High thermal gradients during processing.
- Material-selection constraints associated with laser-processability.
- Complex interaction between powder properties, energy input and thermal history.
Cold Fusion technologies use a different processing strategy.
Instead of relying on complete melting during printing, functional powders are physically combined with binder powders and selectively processed to generate a green part. Shape definition occurs during printing, while densification is subsequently achieved through controlled debinding and sintering when required by the selected material system.
What are Cold Metal, Ceramic and Exotic Powders Fusion?
Cold Fusion SLS processes are based on:
- Physical mixing of the functional powder or fiber with the selected binder powder.
- Selective processing to build the green part.
- Retention of the printed geometry without molds or tooling.
- Subsequent debinding and sintering where required to obtain the final material.
Because the geometry is created directly during powder-bed printing, these routes provide a direct additive manufacturing pathway for materials that may be difficult to process through conventional melting-based SLS approaches.
Cold Fusion technologies by 3Dresyns
Cold Metal Fusion (CMF)
Cold Metal Fusion uses binder-based powder systems for direct SLS printing of metal-containing green parts followed by controlled debinding and sintering.
The approach is designed to support:
- Processing of a broader range of metal powder systems.
- Reduced thermal loading during the printing stage.
- Controlled dimensional development through printing, debinding and sintering.
Cold Ceramic Fusion (CCF)
Cold Ceramic Fusion applies binder-based SLS processing to technical ceramic powders that subsequently undergo debinding and high-temperature sintering.
The approach is designed to support:
- Processing of technical ceramic powder systems.
- Retention of green-part geometry before sintering.
- Integration with established ceramic debinding and sintering workflows.
Cold Exotic Powders Fusion (CEPF)
Cold Exotic Powders Fusion extends the binder-based powder approach to non-conventional and functional powder systems, including:
- Nanoparticles and nanowires.
- Microfibers.
- Functional fillers.
- Hybrid powder and fiber systems.
This expands the range of functional materials that can be investigated through powder-based additive manufacturing.
3Dresyns bio-based binder powders for Cold SLS printing
3Dresyns develops non-photoreactive, bio-based binder powders for Cold Fusion processing of:
- Ceramics.
- Metals.
- Polymers and high-performance plastics.
- Exotic and functional powders or fibers.
The binder powders are designed for physical mixing with the selected powder system, avoiding the need for complex chemical surface modification as part of the standard preparation route.
Key features of 3Dresyns Cold SLS binder powders
Depending on the selected binder version, functional powder and processing route, the systems are designed to provide:
- Compatibility with a wide range of powders and fibers.
- Water- or solvent-based debinding options.
- Bio-based binder formulations with >90% bio content.
- Physical dry mixing using conventional powder-mixing equipment.
- Adhesion and powder-mixture stability after preparation.
- Processing of micron and submicron powder systems.
- Powder loadings up to approximately 60 vol%, depending on powder morphology, particle size, surface area and material type.
- Use with compatible polymer-powder SLS platforms after process validation.
Debinding, sintering and dimensional control
After printing, Cold Fusion green parts can undergo controlled debinding and sintering using processing routes such as:
- Water debinding.
- Compatible solvent debinding.
- Thermal debinding.
- Sintering according to the requirements of the selected powder system.
The post-processing route must be adapted to the binder, functional powder, geometry and required final properties.
Process development can include:
- Control of dimensional change during debinding and sintering.
- Optimization of heating and debinding profiles.
- Reduction of cracking or deformation during post-processing.
- Adjustment of powder loading and binder concentration.
Printable feature size and final resolution depend on the powder particle size, powder morphology, binder distribution, printer characteristics and selected processing conditions.
Advantages of Cold Fusion SLS technologies
Compared with complete laser-melting routes, binder-based Cold Fusion processing can provide:
- Expanded material compatibility.
- Lower thermal loading during the printing stage.
- Mold-free additive manufacturing.
- Controlled green-part formation.
- Separation of shape generation from final densification.
- Access to non-conventional and functional powder systems.
These characteristics make Cold Fusion SLS particularly relevant for research, functional prototyping, process development and advanced manufacturing applications.
Typical applications
Cold Metal, Ceramic and Exotic Powders Fusion can be applied to areas including:
- Technical ceramic components.
- Metal components.
- Functional polymer and composite parts.
- Parts incorporating nanomaterials, fibers or functional fillers.
- Research and experimental material systems.
- Advanced functional devices.
Customization and process development
Cold Fusion processes are highly dependent on the selected powder, binder system, printer, geometry, debinding route and sintering conditions.
3Dresyns supports process development through:
- Binder powder selection and customization.
- Optimization of powder-to-binder ratios.
- Powder-mixing process development.
- Debinding and sintering process development.
- Dimensional-control and shrinkage tuning.
- Technology transfer from laboratory development to production implementation.
Cold Fusion process images
