A-prori layer height determination for wire arc additive manufacturing based on weld geometry A-priori-Lagenhöhenbestimmung für drahtbasierte Lichtbogen-Additiv-Schweißverfahren auf Basis der Schweißnahtgeometrie

The application of wire arc additive manufacturing (WAAM) for the production of large size components is currently limited, due to strong distortion and unprecise filling behavior. The resulting geometric and metallurgical irregularities pose a challenge to the process. The current approach of a layered structure cannot be adopted without adjustments when using wire arc additive manufacturing. Reasons include incompleteness, material accumulation and deformation. The combination of experimental weld geometry-determination and its numerical estimation is presented here as solution to this challenge. The procedure is based on the measurement of a weld bead cross-section-area. By convolution of a path matrix with a weld-geometry-function, the planned path is filled with the seam geometry. Subsequent summation of multiple matrices results in a height profile showing discontinuities and accumulations. Further validation tests show a good agreement between the method and experimentally determined problem areas. The presented optimisation procedure can be extended with material parameters. A local compensation for deformation can be achieved.