OBRABOTKAMETALLOV Vol. 24 No. 3 2022 TECHNOLOGY Ta b l e 1 System characteristics Characteristics Designation Dimension Value Substrate size L × B × H mm 20×10×3.5 Wire diameter dw mm 1.2 Wire feed speed Vwf mm/sec 30 Substrate motion speed (deposition speed) Vs mm/sec 15 Diameter of heat sources (electron beams) D mm 1.5 Thermal power of each source Q W 350 Azimuthal angle of the heat sources action α ° 45/15 Ta b l e 2 Thermal physical characteristics of 04Cr18Ni10 steel used in the calculation Characteristics Designation Dimension Value Melting temperature Tmelt K 1.800 Specifi c heat capacity Cp J·kg -1·K–1 710 Density ρ kg·m–3 7.680 Thermal conductivity λ W·m–1·K–1 26 Enthalpy of fusion Hf J/kg 276.000 Boiling Point Тevp K 3.133 Enthalpy of evaporation Hevp J/kg 351.000 Dynamic viscosity μ Pa·s 0.007 Surface tension coeffi cient σ N·m−1 1.615 Temperature coeffi cient of surface tension γ = dσ/dT N·m−1·K−1 –0.00043 Investigation of the infl uence of mutual positioning of the deposition velocity vector relative to the action plane of electron beams. Figs. 2 and 3 show the results of numerical analysis of the deposition process of vertically fed wire material, fused by two symmetrically acting electron beams, without (a) and with (b) the forces of metal vapor pressure. Fig. 2 shows a variant in which the deposition velocity vector lies in the action plane of the electron beams, and Fig. 3 shows a variant in which the deposition velocity vector is perpendicular to the action plane of the electron beams. The results testify that the geometric characteristics of the deposited beads signifi cantly depend on the relative position of the deposition velocity vector relative to the action plane of the electron beams. Without taking into account the vapor pressure forces, in both cases we observe the formation of fairly uniform rolls without signifi cant distortion of the fusion line and the stream transfer of the fi ller material into the melt bath. The vapor pressure force and its accounting has a signifi cant impact on the results of numerical simulation of the formation of the welding pool and the hydrodynamic processes occurring in it, as it is known that the vapor pressure forces are the main driving force in the weld pool [22]. The mode of the fi ller material transfer also changes.
RkJQdWJsaXNoZXIy MTk0ODM1