Cross-material modelling of DED-LB deposition geometries considering the substrate temperature and material-specific properties

The wire-based laser-directed energy deposition (DED-LB-w/M) is an additive manufacturing process known for high build rates, material efficiency, and industrial applicability. However, the process is prone to instabilities caused by an incorrect working distance, which motivates the development of models predicting the deposited weld bead geometry to facilitate planning of slicing and path planning. While prior studies primarily focused on laser power, wire feed rate, and traverse speed, this study extends the parameter space to include substrate temperature and focal plane variation of the laser spot. Additionally, a cross-material modelling approach and the integration of material properties into the modelling framework aim to eliminate the need for refitting the model for new materials. Similarity-based and empirical statistical models are employed to predict individual weld bead geometry. The investigated models have been validated for three materials (316L, Inconel718, AlSi5). Results show that bead height is reliably modelled across materials using combined statistical parameters. The developed models support adaptive path planning, compensation for geometric substrate inhomogeneities, and efficient parameter optimization. Integrating these models into Cyber-Physical Production Systems enables the incorporation of material- and machine-specific properties into the process control loop, facilitating both offline process development and real-time adaptive response to anomalies, thereby enhancing process stability and enabling fabrication of non-planar slices.