Determination of the control points for circle and triangle route in wire arc additive manufacturing (WAAM)

Abstract

Complex builds make wire arc additive manufacturing (WAAM) difficult to control the uniformity of deposit shapes and sizes. Here we develop, test and combine a three-dimensional heat transfer and fluid flow model of WAAM with corresponding experiments to get the control points location to form ideal deposit shape and size in the circle route and triangle route. The heat and fluid flow model of complex build is established by considering the circle route and triangle route in the top surface boundary conditions. The deposit progress, deposit shape and thermal cycles of circle route and triangle route are calculated for various arc powers, travel speed and wire feed rate. The results agree well with the corresponding experimental results. The well tested model provides a calculation method to find the control points during the complex build additive manufacturing. Combining with simulation results, the control points of the circle route and triangle route are obtained to improve the uniformity of deposit. The control points for circle route are set within 0.4 mm from the positions where the tangent is horizontal or vertical. The control points for triangle route are set within 0.2 mm from the inner corner.