A study on power-controlled wire-arc additive manufacturing using a data-driven surrogate model

Abstract

Wire-arc additive manufacturing (WAAM) provides an alternative for the production of various metal products needed in medium to large batch sizes due to its high deposition rates. However, the cyclic heat input in WAAM may cause local overheating. To avoid adverse effects on the performance of the part, interlayer dwelling and active cooling are used, but these measures increase the process time. Alternatively, the temperature during the WAAM process could be controlled by optimizing the welding power. The present work aims at introducing and implementing a novel temperature management approach by adjusting the weld-bead cross-section along with the welding power to reduce the heat accumulation in the WAAM process. The temperature evolution during welding of weld beads of different cross-sections is investigated and a database of the relation between optimal welding power for beads of various sizes and different pre-heating temperatures was established. The numerical results are validated experimentally with a block-shaped geometry. The results show that by the proposed method, the test shape made was welded with lower energy consumption and process time as compared to conventional constant-power WAAM. The proposed approach efficiently manages the thermal input and reduces the need for pausing the process. Hence, the defects related to heat accumulation might be reduced, and the process efficiency increased.

End-to-End Path Planning for Homogeneous Temperature Fields in Additive Manufacturing

“…Another potential implication involves the microstructure and, consequently, the mechanical properties of the part. Israr et al (2021) show that regulating the welding preheat temperature of ER70S-6 leads to a finer microstructure, higher toughness and yield strength. The improvement in the field homogeneity found in Table 4, suggests that the optimized parts present reduced microstructural variability.…”

Reinforcement of Tooling Using Residual Stresses Generated by Cladding by Arc Welding

“…Table 1 presents the various parameters of Goldak's heat source used in this study. The parameters n = 1, v = 7.5 mm/s, and f = 1 remain constant for all the models, while the remaining heat source parameters are changed according to the bead shapes, as explained in previous work [53,[58][59][60]. The welding parameters for all simulations were kept the same.…”

Design of a Cost-Effective and Statistically Validated Test Specification with Selected Machine Elements to Evaluate the Influence of the Manufacturing Process with a Focus on Additive Manufacturing

“…The control of the machine movement to generate the desired part geometry is mostly realised via NC code processed by a CNC machine or a robot. The process parameters with the most influence are the welding power, welding speed, and shielding gas composition [6][7][8]. Up to date, a wide range of possible AM processes covering different materials and energy sources are available.…”