Preventing Powder Contamination in Selective Laser Sintering (SLS)
18 patents in this list
Updated:
A clean, uncontaminated powder is essential for a successful 3D printing process using Selective Laser Sintering (SLS). Parts that are weak or defective as a result of contaminated powders can affect safety and functionality in vital industries like aerospace and medicine.
This page examines a number of recent developments used to guard against powder contamination in SLS.
1. Sterile 3D Printing System for Implantable Bone Scaffolds with Contamination Prevention
OsseoPrint3D LLC, 2023
3D printer to print implantable bone scaffolds in an aseptic environment. The printer uses a sterile cartridge of biodegradable printing material. A movable sterile receiving plate catches the printed scaffold. A cover with UV light maintains the aseptic environment inside. The cover has a filter and positive airflow to keep out contaminants. The printer also has a heater to melt the printing material for extrusion. The sterile cartridge and receiving plate can be replaced for each print to ensure sterility.
2. Enhanced Cleaning Method for 3D Printer Heads in Selective Laser Sintering
Seiko Epson Corporation, 2023
Device and method to improve cleaning of 3D printer heads to avoid clogs and material deposition issues when changing materials. After printing a layer, the printer head flushes the nozzle by discharging a higher voltage and/or longer duration of fluid to a position outside the printed area. This higher voltage flush reduces clogging and removes powder particles from the nozzle tip.
3. Smart Storage Container with Environmental Monitoring for Additive Manufacturing Powders
LPW TECHNOLOGY LTD., 2023
A container for storing powders, such as those used in additive manufacturing (AM) processes, that includes sensors to monitor and log parameters like oxygen level, humidity, temperature, pressure, weight, location, etc. The container has a pressure vessel with an outlet valve and contains powder and pressurized gas. The sensors track conditions inside the container to maintain powder quality. A control unit records and communicates the sensor data to a remote station.
4. Sealed Filament Pathway System for Moisture Prevention in 3D Printing
Stratasys, Inc., 2023
A filament feed system for 3D printers to enable sealed filament pathways to prevent moisture absorption. The system uses detachable filament supplies with connector keys that plug into printer receptacles. The keys have different shapes to fit specific receptacles. They also have guide tubes to enclose the filament path from the supply to the printer. The keys seal the receptacles to prevent air/moisture ingress.
5. Enhanced Depowdering Process for Selective Laser Sintering with Liquid Agitation and Filtration
Desktop Metal, Inc., 2023
Depowdering additively manufactured parts containing bound metal powder by immersing the parts in a liquid-filled container, agitating the liquid to dislodge unbound powder from the parts, and filtering the liquid to recover the powder. The agitation may be mechanical vibration, gas jets, or heating to create currents that carry away the loose powder. The filtering separates the powder from the liquid for reuse or disposal.
6. Selective Powder Removal with Binder-Safe Cleaning Liquid for SLS 3D Printed Parts
Ricoh Company Ltd., 2023
Cleaning liquid for post-processing additive-manufactured parts. The cleaning liquid is used to remove excess powder from 3D-printed metal parts without dissolving the binder resin used in the printing process. The cleaning liquid contains a hydrocarbon solvent with a high octanol/water partition coefficient of 4.5 or more. This solvent property allows selective removal of powder while leaving the binder intact.
7. Automated Fixture for De-powdering Components in Selective Laser Sintering Processes
Hamilton Sundstrand Corporation, 2023
Automated fixture for removing loose powder from additively manufactured components like 3D printed parts. The fixture holds the build plate with the printed component and inverts it. Pneumatic knockers strike the inverted plate to shake the loose powder out of the component via gravity and resonance.
8. Nozzle Cleaning Mechanism for Preventing Material Leaks in 3D Printing
Seiko Epson Corporation, 2023
Three-dimensional shaping apparatus and method for 3D printing that allows cleaning the nozzle during printing to prevent material leaks. It has a cleaning mechanism separate from the print area that can be activated mid-print to clean the nozzle. The cleaning process is triggered when pressure in the nozzle exceeds a threshold. The nozzle moves to the cleaning area, is cleaned, and then returns to printing once pressure is normal. This prevents material leaks during printing that can mar the object being printed.
9. Reactive Powder Bed Technique for Contamination-Free Selective Laser Sintering
PALO ALTO RESEARCH CENTER INCORPORATED, 2023
3D manufacturing technique using reactive powder beds to print objects with cross-linked regions. The method involves depositing layers of powder containing a first component. Then dispense a liquid containing a solvent and a second component that reacts with the first component when cross-linking occurs when the solvent evaporates. The process iterates to form subsequent layers until the object is complete. Unwanted particles are removed. The powder bed holds the particles and print heads dispense the reactive liquid.
10. Smart Acclimation Container for Powder Management in Selective Laser Sintering Processes
LPW Technology Ltd., 2023
A container that can determine if the powder inside has acclimated to ambient conditions before opening compares the inside temperature/humidity to outside readings and provides an indication if the powder is ready to use. The container has sensors inside and outside and a lock that prevents flow until acclimated, preventing moisture issues from temperature changes.
11. Wetted Powder Removal System for Enhanced Safety in Selective Laser Sintering Processes
Hamilton Sundstrand Corporation, 2022
Powder removal system from enclosed additive manufacturing systems like powder bed fusion 3D printers. The system captures powder in a separate wetted collection volume to reduce dust and explosion risk compared to dry transfer. It uses a valve to control powder flow and wetting agent to capture the powder. A moisture trap prevents collected moisture from reaching the printer volume.
12. Gas-Fluidized Cleaning Process for Metal Powders in Additive Manufacturing
Hamilton Sundstrand Corporation, 2021
Cleaning metal powders used in additive manufacturing to remove adsorbed species like oxygen, moisture, and other contaminants. The cleaning process involves fluidizing the powder in a reactor using gases like argon, ammonia, hydrogen, or nitrogen. The upward gas flow through the powder displaces and removes the unwanted surface species.
13. Innovative Seal-Less Container Design for Powder Contamination Prevention in SLS Machines
Freemelt AB, 2021
A powder bed additive manufacturing machine that is able to seal the powder compartment without any additional sealing elements. This is achieved by using a container design where the inner walls can move up and down while still preventing powder from flowing out. The inner walls overlap with the outer walls so when the inner walls move upwards, the powder above is pushed up but cannot flow out due to the overlapping walls. This allows the machine to seal the powder compartment without any additional seals that can degrade or fail. The inner walls move up to reduce the volume and expose the powder for layer distribution.
14. Modular Forming Device for Contamination-Free Selective Laser Sintering
REALIZER GMBH, 2019
A modular and interchangeable forming device for 3D printing objects from metal or ceramic powders. The device has interchangeable modules that contain the powder supply, powder recovery, gas purging, suction, and data processing components. The modules can be swapped out for different powder materials to avoid contamination. The modules connect to the process chamber for powder circulation during printing. After printing, the modules containing the powder, filters, pumps, and storage can be easily exchanged for cleaning and switching powder materials.
15. Innovative Powder Cartridge System for Clog-Free Selective Laser Sintering Operations
JEOL Ltd., 2015
Additive manufacturing machine that prevents clogging and contamination during powder-based 3D printing. The machine uses a removable powder cartridge with a small discharge port. The cartridge has rotary blades near the port that prevent powder from solidifying and clogging. This stable powder dispensing prevents clogs during printing. The cartridge can be easily exchanged to switch materials.
16. Advanced Powder Recycling System for Selective Laser Sintering 3D Printers
MICROJET TECHNOLOGY CO., LTD., 2015
Close-loop powder recycling system for 3D printers that recycles powder from the printer chamber to reduce waste and cost. The system uses a cyclone separator, particulate filter, and electrostatic precipitator to separate and filter remaining powder for reuse. The recycled powder is fed back into the printer. This allows multiple filtering steps to adjust particle size distribution. The system also includes components like a collector and breaker to efficiently collect and transfer the recycled powder.
17. Vacuum-Assisted Powder Preparation for Contamination-Free Selective Laser Sintering
ASPECT INC., 2014
A powder rapid prototyping method and apparatus that allows the use of metal powders without oxidation or nitride contamination. The method involves removing oxygen, nitrogen, and water from the metal powder prior to modeling by exposing the powder to a vacuum. The powder is housed in separate containers inside a vacuum chamber. This prevents oxidation and preserves the purity of the metal during the modeling process. The vacuum-exposed powder is then layered and sintered using energy beams to build 3D models.
18. Automated Powder Handling System with Vacuum Transfer for 3D Printing
Thomas Davidson, 2011
A powder handling system for 3D printers that allows powder to be transferred between multiple receptacles using a vacuum source and valve. This enables efficient automated powder management for 3D printing with minimal dust and waste. The system includes multiple powder holding receptacles (dispensing hopper, build chamber, overflow container), a vacuum source, and a valve to selectively connect the vacuum to each receptacle. Powder can be transferred between receptacles without manual handling. The valve prevents dust escaping.
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Exceptional 3D printed parts can be produced because of the patents demonstrated solutions for tackling issues including keeping implantable parts sanitary, streamlining print head cleaning procedures, and using intelligent containers for powder monitoring and storage.