Initial transient phase and stability of annular laser beam direct wire depositionKotar, Matjaž (Avtor) Fujishima, Makoto (Avtor) Levy, Gideon N. (Avtor) Govekar, Edvard (Avtor) additive manufacturinglaserswireIn this paper the stability of the annular laser beam (ALB) direct wire-deposition process, which enables process symmetry and a well-defined ALB workpiece irradiation proportion (WIP) and related energy input onto the workpiece and the wire surface is considered. Various initial process phase strategies with respect to different initial wire-end positions and WIPs were analysed based on the process visualization and outcome, and the melt pool temperature. It was shown that in addition to a precise synchronization of the mutually time-dependent ALB power, wire and workpiece feeding velocity, the fastest and the most robust transition into a stable stationary process could be achieved with the initial position of the wire-end on the workpiece surface. Additionally, the WIP was shown to have a strong and nonlinear influence on the process stability.20192019-07-05 10:21:42Članek v reviji108519UDK: 621.791(045)ISSN pri članku: 0007-8506DOI: 10.1016/j.cirp.2019.04.118COBISS_ID: 16601883OceCobissID: 170267sl