Depending on the mechanism involved in its creation, each type of particles has specific physical characteristics that can impact powder recyclability and contribute defects to the final products. Two key mechanisms are responsible for spatter formation and powder bed denudation in the vicinity of the laser track. Let’s have a look at these.
A few months ago, we were wondering about process control in powder bed fusion of reactive powders. What are the impacts of particles’ surface contamination on the fabrication of metal components? And what are the best ways to minimise it during the complete manufacturing cycle?
Then, very few studies were trying to assess the impact of powder particles surface chemistry on the process (powder spreading, melt wettability, pores formation, etc…) and on the final product characteristics (relative density, etc). As more data get publicly available, we can present the results of a detailed investigation aiming to 1) understand the effects of powder surface chemistry, 2) minimise particles surface contamination on the finished products and 3) improve SLM process control.
Researchers at the University of Sheffield, UK, are developing a new additive manufacturing technique that aims to minimise the presence of residual stresses in components. The project, funded by EPSRC UK, aims to develop a novel, low cost metallic Additive Manufacturing process that induces low thermal stress during manufacturing: Layered Extrusion of Metal Alloys (LEMA).
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