Preparing 3D Functional Gradients for SLS

Abstract:

The creation of three dimensional functional graded materials by powder processing methods requires the capability to arrange a sequence of two dimensional images that can be presented to a solid freeforming device. Planar stacking methods can only achieve a one dimensional gradient. We describe the acoustic control of powder metering and dispensing valves in which the flow rate and switching of powders from a capillary can be controlled using the frequency and amplitude of acoustic vibration from a computer sound card. An orchestra of such valves can be used to pattern layers of powder on the building platform which forms part of a 3-axis table in the Selective Laser Sintering (SLS) process. Patterns and gradients were prepared using copper and steel powders.

• Periodical: Materials Science Forum (Volumes 492-493)
• Pages: 749-754
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.492-493.749
• Online since: August 2005
• Authors: Shou Feng Yang, Julian R.G. Evans
• Keywords: Functional Graded, Powder Dispensing, Powder Flow, Solid Freeforming

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