INFLUENCE OF RARE-EARTH ELEMENTS ON THE STRUCTURE AND PROPERTIES OF WELDS OF VT22 TITANIUM ALLOY

摘要

The paper presents the results of investigations of the influence of rare-earth metal fluorides on structural changes in weld metal of titanium alloy VT22 for the purpose of using them in the flux filler of experimental flux-cored wire for welding this alloy. It was shown that refinement of β-grains is observed in welds made by argon-arc welding of VT22 alloy over a layer of flux, consisting of rare-earth metal fluorides. Addition of LaF_3 to the core of experimental flux-cored titanium wire PPT-22 in combination with heat treatment allowed increasing the impact toughness of welds in argon-arc welding of VT22 alloy 2 times up to 30.6 J/cm~2.