Evaluating H13 Printing Parameters For Wire-Ded Hybrid Manufacturing Process

The increasing industrial demand for efficient tool-steel repair strategies has driven interest in wire-fed Laser Directed Energy Deposition (LW-DED), a process for which there is significantly less documentation than for powder-based DED systems. This thesis investigates the deposition behavior of AISI H13 tool steel using a hybrid additive–subtractive manufacturing platform equipped with wire-based deposition and CNC machining, with the aim of identifying stable parameter windows suitable for future repair applications. The study integrates wire characterization, DED process programming, controlled single-bead experiments, metallographic evaluation, geometric measurements, dilution quantification, and statistical analysis to establish a foundational understanding of LW-DED H13 behavior. A structured Design of Experiments (DoE) was implemented to examine the interactions among laser power, travel speed, and wire feed speed. Two experimental plates were produced, from which bead cross-sections were prepared to evaluate dilution, bead geometry, fusion quality, and defect populations. The best-performing conditions were identified on Plate 2 (bead 9) and Plate 3 (beads 3 and 7), whereas most remaining conditions, particularly those on Plate 2, exhibited unstable geometry or excessive dilution. While the literature reports typical dilution levels of 13% 30% for H13, the present experiments produced values of 55%-65%, attributed to deposition on a mild-steel substrate and the off-axis wire–laser interaction inherent to the experimental setup. Metallography showed no incompatibility between the material and the bead, with a predictable heat-affected zone approximately 0.5 mm below the bead. Statistical modeling revealed that wire feed speed is the most influential factor on both dilution and bead height, while travel speed strongly affects geometric stability; in contrast, power–travel and power–wire feed interactions were generally insignificant. Overall, this work demonstrates that LW-DED H13 exhibits a narrow, highly sensitive operational window, in which stable deposition requires careful coordination of thermal input and wire delivery. The results contribute new experimental data to the limited body of literature on wire-fed H13 processing and establish a methodology for evaluating process behavior through combined geometric, metallurgical, and statistical assessments. The findings confirm the feasibility of depositing H13 wire in a hybrid machine and lay the groundwork for future development of repair strategies involving combined wire and powder deposition, followed by CNC finishing.