Methods For Defining The Concentration Of Nanostructured Powders In Protective Gas And Its Effect On The Microstructure Of Deposit Metal

摘要

The effect on the deposited metal structure of nanostructured modifiers introduced into the weldpool has been studied. Methods have been developed for determining the concentration of nanostructured powders of tungsten, molybdenum and Al_2O_3 in protective gas and for defining their optimal concentration. The influence of nanopowders on the structure of deposited metal was examined in consumable electrode arc welding employing the austenitic steel (chemical composition: C - 0,12%, Cr - 18%, Ni - 10%, Ti - 1%) as deposit and 1.2-mm welding wire manufactured from the austenitic steel (chemical composition: C - 0,12%, Cr - 18%, Ni - 9%, Ti - 1%). Addition of nanostructured powders of tungsten, molybdenum and Al_2O_3 to the weldpool has shown positive effect on the structure of metal in arc welding. It is shown that introducing the powders decreases dendrite size and leads to the formation of a more equilibrium microstructure of the weld.