Recent work has shown the possibility of hybridizing directed energy deposition (DED) processes, with interlayer plastic deformation to refine the grain structure and improve mechanical properties. The plastic strain stored in the build during deformation can trigger recrystallization under the inherent heating from subsequent laser deposition, leading to a finer, more equiaxed grain structure. In this work we study the effect of the deformation level on the final microstructure evolved by applying interlayer hammer peening to laser DED fabricated Inconel 625. Microstructural evaluation indicates that under extreme deformation levels, a fine grain structure of ~3μm is formed. Further analysis also reveals that the complex thermal conditions imposed by the laser, lead to a heterogeneous grain distribution consisting of both recrystallized and non-recrystallized grains. The results of this work highlight the possibility of spatial microstructure control through interlayer deformation and elucidate some of the process-microstructure relationships.

In recent years the demand in Smart and Technical Textiles increased, especially with incorporated sensors and actuators. However, current conductive textile structures, achieved by integrating conductive yarns, wires and strands or by conventional coating and printing technologies, lack kink resistance and reliability. The latter do also lack the needed grade of functionalization.

The proposed process allows the application of a multi-material powder compromising a blend of a polymer powders and a high amount ( > 50 wt%) of functional pigments e. g. metal particles.

The technology is based on a nozzle based application of the lose powder mixture and a subsequent laser fixation step. This enables the fabrication of individualized and highly functionalized coated substrates based on a digital data set.

The Directed Energy Deposition (DED) process is highly influenced by the mass flow of metal particles. Higher mass flow increases productivity by creating thicker layers but also complicates melt pool stability due to residual heat accumulation in the solidified material. This overheating disrupts thermal properties, affecting the fluidity of the liquid metal and potentially destabilizing the process, leading to defects or geometric inconsistencies.

This study presents an advanced thermal model incorporating domains with adjustable properties to simulate the part's growth and address these challenges. A virtual closed-loop PID controller is integrated into the model to calculate optimal laser power in real time, compensating for accumulated heat and maintaining a stable temperature in the laser-material interaction zone.

Experimental validation confirms that applying the model's predictions ensures process stability, enabling the production of components with consistent quality and desired properties.

Blister-Actuated Laser-Induced Forward Transfer (BA-LIFT) uses a polyimide layer to decouple laser-material interaction, enhancing control over transfer dynamics. This study combines experiments and simulations to analyze blister formation and its role in material ejection. High-speed imaging reveals oscillatory blister behavior, modeled using polynomial fits for numerical predictions. A Phase-Field model in COMSOL Multiphysics simulates jet formation and secondary effects, incorporating cavitation bubbles observed experimentally. Findings suggest that the blister-induced velocity field triggers cavitation at the polyimide-fluid interface, impacting transfer efficiency. Additionally, investigations into LIFT for high-viscosity pastes show that substrate spacing dictates whether material forms a continuous jet or disperses. A novel FEM-CFD model enables printability maps predicting paste behavior. These insights improve predictive control and optimization of LIFT techniques, broadening material applicability.