Problems of high-manganese steels welding

The sensitivity of high-manganese steels to deformation and heat treatment leads to problems with their welding. They consist in the tendency to crack formation in the zone of thermal influence during rapid heating and cooling. They are also characterized by sensitivity to overheating, which is expressed in the possibility of the carbides precipitation and structure heterogenization. Tendency to cold-hardening due to welding stress can also cause micro- and macro-defects and reduce the quality and reliability of the welded joint. The work represents analysis of the modern global experience of high-manganese steels welding in various ways and with the use of various materials. The importance of maintaining the homogeneity of the chemical composition between the weld metal and the base material is shown in order to prevent the formation of martensite due to an austenite stability decrease. While welding dissimilar steels, the release of harmful carbides can occur, so such joints should be preheated with controlled cooling. Welding of high-manganese austenitic steels is not recommended to be performed with a consumable electrode made of stainless austenitic steel due to the formation of significant structural and phase heterogeneity, eutectics and cracks that can pass from the welding zone through heat affected zone to the base metal. As a result of the research analysis, it was established that the welding of high-manganese steels is best performed with electrodes with a chemical composition that is close to the materials being welded. Before welding, it is recommended to reduce the level of residual stress and cold hardening by heat treatment. Welding should be carried out under the conditions of minimizing the thermal load on the material, which is achieved by low-current and short-seam welding, as well as by preheating the metal. For welding thin parts from high-manganese steels, laser welding can be used. For larger thicknesses, welding with a fusible electrode in an environment of shielding gases (MIG\MAG) and argon arc welding with a non-fusible electrode (TIG) is applicable.