(2f) Comparison of Different Flow Assessments for Selective Laser Sintering Powders

Authors: 
Riedl, E., Anton Paar Gmbh
Hartmann, K., Anton Paar Gmbh
Schütz, D., Anton Paar
Selective Lase Sintering (SLS) is a rapidly expanding field of manufacturing technology. Its raw materials are manifold spanning both high density as well as low density metal powders and extending into polymers and ceramics as well.

While currently strict criteria are applied towards the sphericity of the particles as well as having an extremely narrow size distribution, this puts a considerable strain on the manufacturers of such powders, especially cost wise, and severely limits the availability of exotic materials for high performance engineering purposes.

While ring shear testers are a well-developed and standardized method for the characterization of flow behaviour it is often found to be lacking with especially free flowing powders such as the raw materials for SLS machines.

Several alternative methods (two methods for tensile strength testing, Rotational Cohesion Testing, uniaxial testing, penetration testing) will be compared both from the standpoint of particulate mechanics as well as the perspective of the practical process engineer as well as finally compared to the effectiveness of the proven ring shear tester.

This includes an assessment of the particulate mechanics of such systems as well as extensive experimental work and application of low and high density metals as well as polymer raw materials.

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