Title screen

[References: 4 tit.]

As a result of heterogeneity of thermal fields during welding the internal structure of seams becomes highly heterogeneous with grain coarsening and microdamages that determines their strength properties. It is necessary to have a theoretical basis for a deeper understanding of the processes of structure formation in welded joints to improve the quality of welded joints particularly at low temperatures. By means of numerical methods an influence of low temperatures on the structural phase features of welded joint formation in gas tungsten - arc welding is considered in this work. A technique for applying the invariant theory to evaluate the structure of the material at the design stage of the technological process for the given welding regimes has been developed. It is shown that the calculation results are in good agreement with the experimental data.