This week was chock-full of news related to metal AM. The global scene is intensely researching the potential of metal AM and competitiveness is growing in all its aspects: metal powder production, CAD optimization, manufacturing method and much more. This week we saw exposed not one, but two new methods of metal AM! LLNL and the University of Sheffield both came out with novel techniques to produce produce metal objects additively and they both have their own unique benefits, being that increased speed or greater reliability. All the while we are making strides in understanding the complex physics involved in metal sintering processes: greater knowledge and improved optimization software is also crucial to manufacture metal parts reliably and efficiently.
Lawrence Livermore National Laboratory announces new metal 3D printing method
US federal research facility, Lawrence Livermore National Laboratory (LLNL) has announced the results of an ongoing three-year research project into direct metal 3D printing. The technology, referred to as ‘Direct Metal Writing’ (DMW) adds to existing metal additive solutions such as selective laser melting (SLM). […] The new approach uses semi-solid metal feed material, beginning with a heated ingot or small block of metal. Once heated to a semi-solid state, the metal is then pushed through the extruder in a paste-like consistency. The material is shear thinning, which means it forms as a solid when left to rest and acts more like a viscous liquid when in motion or when applied with force.
Read more about DMW here.
Significant Speed Up For 3D Metal Printing Developed
Researchers at the University of Sheffield have developed a unique 3D metal printing process that could dramatically speed up metal printing. […] they call “Diode Area Melting”, or “DAM”. Instead of a single (or small number of) lasers, the DAM approach involves using an array of low power laser diode emitters. These emitters are not directed to the powder by an arrangement of mirrors, but instead are positioned above the powder surface and apply their energy directly.
Read more about DAM right here.
Challenges in modeling and simulation for metal additive manufacturing
Commercial acceptance of AM for exacting applications still faces a technical challenge caused by the limited understanding of physical phenomena in the melt pool. Real-time observation of this physical phenomena is difficult since AM melt pools are inherently transient and involve complex physical interactions between energy beam-powder substrate. Moreover, the real-time measurements of thermal and fluid variables can typically be made only on the surface of the melt pool. In contrast, a numerical simulation of mass, momentum, and energy transfer in melt pools can provide approximation of the melt pool shape and some useful 3D fields such as the distributions of temperature, flow velocities, solidification temperature gradient and solidification rate. Ultimately, an understanding of the relationships between processing, structure, properties and performance is essential.
Check out both parts of the article, here and here.
There is more where all these came from so don’t forget to follow us on Twitter for daily doses of AM news! And, as always, we hope to see you back next week!
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