Control of Metal Transfer in Additive Shaping of Workpieces: Layer-by-Layer Application of Metal Layers by Plasma Spraying

Abstract: Metal quality must be improved in the additive production of workpieces. Monolithic workpieces of considerable size and mass with specified characteristics may be produced by layer-by-layer application of metal layers on the basis of plasma spraying. However, practically no research has been devoted to this topic. To create high-quality metal layers by this means, the metal particles must be as uniform as possible in terms of shape, size, velocity, and temperature. Satisfactory transfer of material also requires uniform parameters of the two-phase jet over the cross section. It is established that plasmatrons with a series of vortex chambers may be used to create two-phase jets with parameters specified over the cross section and hence to ensure controllable transfer of material from the disintegrating wire. Ensuring that the metal particles are uniform in size and shape, with a transfer coefficient of 0.95–0.97, is a precondition for the use of layer-by-layer plasma spraying in the additive production of metal workpieces. © 2023, Allerton Press, Inc.