Effect of beam deflection oscillations on the weld geometry

•Electron beam welding with beam oscillations at various focus positions is studied.•Weld and HAZ profiles at beam oscillations along and across joint are determined.•Statistical analysis of the experimental data is executed and discussed.•At low focus position and longitudinal oscillations the radius of weld root increases.•Dagger-like weld shape in all other cases confirm hypothesis for beam self-focusing.