Geometrical modelling of a crystal grain in a weld of ferritic stainless steel

The paper deals with modelling of the shape and size of a crystal grain in a butt joint of ferritic high-alloy stainless steel made by TIG welding without the addition of filler material. The optimum, maximum, and minimum current intensities and welding speeds were experimentally determined. The welding speed is mathematically described as a function of the welding-current intensity. On the basis of macro specimens taken from three different directions with regard to the welding direction, the grain shape, size and location in the weld with regard to the welding direction were established. Individual characteristic crystal grains are shown in space. The average grain size was determined and described mathematically as a function of the welding parameters. (orig.)