Chernyak Y. Development of materials and technology of hardsurfacing of worn-out rails in operating tram track

The work is devoted to the development of the new sparsely-alloyed materials, technology and equipment for restoration and strengthening of tram rails on operating tram track, also to the development of metallurgical and technological measures for improvement of quality of deposited parts, made from steels, containing ( 0.4% carbon, without preheating and concurrent heating. It was established that to prevent the crack formation in HAZ, the hardfacing of parts from carbon steels using the austenitic materials should be performed at heat input ( 28 kJ/cm. For hardfacing carbon steel parts without preheating, a radically new system of alloying of a ductile deposited ferritic metal of Fe-Ti-Mn-Si-Mo type is offered. In use of the new electrode material, all carbon, that transfers into deposited metal, is bound into strong titanium carbonitrides according a stoichiometric ratio, uniformly distributed in a ductile ferritic matrix of a high crack resistance. A unique technology of restoration of tram rails without dismantling has been developed. The deposition with a ferritic flux-cored wire PP-Np-T3SGM will guarantee the absence of defects of a cleavage type at the fusion line with the parent metal, and the final beads deposited by the austenitic flux-cored wire PP-Np-G13Kh13N2MF will increase the wear resistance of the as-restored rails.