Speaker
Description
Enabling additive manufacturing of tungsten (W) for components with properties that match or surpass those of conventionally manufactured powder metallurgical (PM) W parts is currently one of the greatest challenges in alloy and process development for PBF LB/M. For W, rapid solidification under steep thermal gradients typically produces coarse, columnar grains and high residual stresses, which drive cracking and limit performance. Notably, even compared to molybdenum (Mo), a material with closely related chemical and physical properties, W is more difficult to process with PBF LB/M due to its higher melting point, greater tendency for columnar growth, and higher cracking susceptibility under typical PBF LB/M thermal cycles. These factors indicate that process tuning alone is insufficient. W requires alloy design tailored to the unique characteristics of the PBF LB/M process.
In this presentation, we identify the major defect initiation mechanisms and investigate alloying strategies aimed at counteracting defect formation by promoting grain refinement to disrupt columnar growth and by purifying grain boundaries from embrittling impurities to suppress crack initiation. Both the theoretical rationale and experimental results are presented.
| Speaker Country | Austria |
|---|---|
| Would you like to publish your paper in the special issue of BHM "Berg- und Hüttenmännische Monatshefte" | No |