Page 29 - IJAMD-1-3

International Journal of AI for
Materials and Design
Prediction of wall geometry for wire arc additive manufacturing

A C

B

Figure 1. Samples and WAAM deposition setup. (A) Bead samples for BH and BW measurements. (B) Multibead samples. (C) Setup for sample production.
Abbreviations: BH: Bead height; BW: Bead width.

A B C

Figure 2. Wall modeling and analysis. (A) Height measurement. (B) Peak-to-valley measurement. (C) Example of laser line profile measurement.

2.2. Input and output selection Table 1. Experimental conditions for the CMT‑based WAAM
process
In a CMT welding system, the welding V and current
parameters are automatically adjusted based on the WFS Input factors Values/levels
selected by the user to ensure stable and continuous metal Voltage (V) 22, 24, and 26
transfer. Factors such as wire material, diameter, welding Travel speed, TS (mm/s) 5, 10, and 15
mode, and type of shielding gas are also considered.
For this study, three independent process parameters Dwell time, Dt (s) 5, 60, and 120
were considered inputs (Table 1). Notably, the selection Distance, D (mm) 10
of TS and V for bead geometry as well as TS and dwell Gas flow rate (L/min) 18
time (Dt) for wall production is fundamental owing to Weld bead length (mm) 120
their substantial influence on the weld bead and wall Abbreviations: CMT: Cold metal transfer; WAAM: Wire-arc additive
characteristics in WAAM. TS affects the deposition rate: manufacturing.
a slower TS results in a taller and wider bead owing to the
deposition of more material at one spot, whereas a faster components. The geometric characteristics of the weld
TS produces a shorter and narrower bead. V controls the bead (BW and BH), along with height (H) and W, were
arc length and heat input: higher voltages generate more selected as outputs.
heat and a broader bead, while lower voltages produce The study employed a full factorial design (for V and TS)
a narrower bead. A constant TS ensures uniform layer to systematically explore the effects of critical welding
deposition, influencing the incremental height of each parameters on BH and BW (Table 2). However, even
layer. Dt, reflecting the period between the deposition when using advanced measurement techniques, slight
of successive layers, is crucial for thermal management. inaccuracies could arise owing to inherent equipment
Adequate Dt allows the deposited layers to cool, preventing limitations and variations along the tracks. A 2% error
excessive heat buildup that can lead to distortions and margin was selected to account for slight variations across
poor interlayer bonding. Appropriate Dt minimizes W three zones of the beads and walls. This experimental
and maintains structural integrity. Thus, the strategic strategy covered all possible combinations of factors at
selection of TS and V for bead geometry, as well as TS and different levels, facilitating a comprehensive analysis
dwell time for wall production, enables precise control of both primary effects and interactions. The following
over the WAAM process, optimizing both the geometric Python libraries for data analysis and optimization were
accuracy and mechanical properties of the fabricated utilized: Pandas and NumPy for data manipulation and

Volume 1 Issue 3 (2024) 23 doi: 10.36922/ijamd.4285