Spatial mapping of powder layer density for metal additive manufacturing via transmission X-ray imaging
نویسندگان
چکیده
Uniform powder spreading is a requisite for creating consistent, high-quality components via bed additive manufacturing (AM), wherein layer density and uniformity are complex functions of characteristics, kinematics, mechanical boundary conditions. High spatial variation in particle packing density, driven by the stochastic nature process, impedes optical interrogation these attributes. Thus, we present transmission X-ray imaging as method directly mapping effective depth layers at process-relevant scale resolution. Specifically, study nominal 50-250 micrometer thickness, created selection commercially obtained Ti-6Al-4V, 316 SS, Al-10Si-Mg powders into precision-depth templates. We find that fraction may be predicted from combination relative thickness compared to mean size, flowability assessed macroscale angle repose. Power spectral analysis introduced tool quantification defect severity function morphology, enables separate consideration sparsity. Finally, studied using multi-layer templates, providing insight how particles interact with both previously deposited material abrupt changes condition. Experimental results additionally purpose-built discrete element (DEM) simulation framework, clarifying competing role adhesive gravitational forces well motion within during spreading.
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ژورنال
عنوان ژورنال: Additive manufacturing
سال: 2021
ISSN: ['2214-8604', '2214-7810']
DOI: https://doi.org/10.1016/j.addma.2021.102197