Ultrasonic vibrating screens transmit high-frequency, low-amplitude ultrasonic energy to the screen, solving the problems of screen clogging, inefficiency, and poor precision encountered by traditional vibrating screens in screening specific metal powders. They have become a key piece of equipment for powder preparation in Additive Manufacturing. Coreal Machinery has compiled some information for your reference.
I. Why does Additive Manufacturing require high-quality powder screening?
In powder bed fusion, the quality of metal powder directly determines the success of a print. Binder jetting, extrusion, and other technologies also rely on high-quality powder.
Major powder issues include:
- Agglomeration: Fine powders clumping together due to static electricity, humidity, and other factors.
- Contamination: This may include hair, dust, sintered particles from previous prints, or foreign matter.
- Particle size unevenness: Mixing recycled powder with new powder can alter the particle size distribution.
If these powders are fed directly into the printer, the following may occur:
- Uneven powder distribution: Agglomerates and impurities can cause obstructions in the powder distribution scraper or roller, resulting in scratches or cavities, directly leading to print failures.
- Void formation: Large particles or agglomerated powder may not be fully melted, causing defects within the part.
- Performance degradation: Impurities and uneven powder distribution can result in substandard mechanical properties in the final part.
II. Unique Advantages
- Excellent screening accuracy: Traditional screening equipment struggles to meet the high-precision screening requirements of Additive Manufacturing for metal powders. The Ultrasonic Vibrating Screen overcomes this limitation with its high-frequency micro-oscillation mechanism.
- Efficient processing of easily agglomerated powders: Metal powders (especially ultrafine powders) tend to agglomerate during storage and transportation. Agglomeration affects the flowability and sintering properties of Additive Manufacturing, leading to print defects. The Ultrasonic Vibrating Screen's high-frequency vibrations break down agglomeration forces and disperse the powder.
- Reduces screen clogging: When screening metal powders, screens are prone to clogging, reducing efficiency and requiring machine downtime for cleaning, impacting production. The Ultrasonic Vibrating Screen's high-frequency vibrations allow the screen to self-clean and reduce clogging, reducing the clogging probability by over 80% compared to traditional screens, thereby increasing equipment uptime and efficiency.
- Minimal damage to powder: Additive Manufacturing requires high physical properties of metal powders, and pre-treatment damage can affect product quality. The Ultrasonic Vibrating Screen's gentle vibrations minimize damage to the powder, preserving its original properties. For example, for gold and silver powders, it balances screening accuracy with powder sphericity and smoothness, providing high-quality raw materials for additive manufacturing.
III. Application Scenarios
- Aerospace – Screening of high-temperature resistant metal powders
- Medical implants – Screening of medical metal powders
- Automotive – Screening of lightweight metal powders
- Ceramic printing – Screening of easily agglomerated ceramic powders
Ultrasonic Vibrating Screens, with their superior anti-clogging capabilities, high-precision screening efficiency, and excellent powder property protection, have become an indispensable quality gatekeeper in the Additive Manufacturing industry chain.
Coreal Machinery is committed to providing you with high-quality screening equipment and industry solutions.