Local absorptivity modulation of a 1 μm-laser beam through surface waviness

摘要: Abstract In laser materials processing operations such as deep penetration welding, the beam often interacts with a wavy, molten surface. This wavy topology strongly modulates local angle of incidence rays across surface and in turn absorptivity, which is described by Fresnel-equations. this paper modulation absorptivity modelled over two-dimensional steel for prescribed high power lasers wavelength about 1 μm, like disc, fibre, Nd:YAG or diode lasers. It has become apparent that even regular peaks valleys causes complex distribution at surface, including significant shadowing domains due to grazing during processes drilling cutting. contrast smooth melt, waviness tends towards an angle-averaged 33% 1 μm-lasers steel. The sensitivity on significantly density process mechanisms, boiling accompanied recoil pressure.