Microstructural transformations by heat effect in a dissimilar joint of 17-4PH steel and Hastelloy C-267 superalloy

Abstract

The heat effect produced by the welding on the microstructural variations of a dissimilar joint of precipitation hardening, 17-4 PH (type AISI 630) and the B 574 (Hastelloy C-276) was analyzed. To determine this effect, the electrode E NiCrMo-4 with a diameter of 3.2 mm was used, the deposit was made in joints prepared with bevels of 60o in "V" and butted, welded by only one side of the material. After the welding process the thermal influence area, the interface, and the molten zone were microstructurally characterized. From the effect of the supplied heat, the presence in the microstructure of austenitic associated to the austenite of lath or dendrite morphology was determined, as well as the presence of austenite Widmanstätten and precipitation of secondary austenite inside the martensite.

Keywords

• soldadura disímil
• cambios microestructurales
• acero edurecible aisi 630
• superaleación b 574
• zona fundida
• zona de influencia térmica.