Effect of WC nanoparticles on the cobalt based overlay deposited on H13 steel by a plasma transferred arc (PTA)

• DOI: https://doi.org/10.22533/at.ed.317492414032

• Palavras-chave: Plasma Transferred Arc (PTA) , H13 steel

• Keywords: Hardfacing; Tungsten carbide; H13 steel; Particle reinforced composites; PTA process.

• Abstract: Plasma Transferred Arc (PTA) is a process used to repair H13 steel, in which the weld deposits are characterized by low levels of inclusion and an improvement in wear resistance. In this investigation, tungsten carbide                  nanoparticles (WC NPs), with a size of 80 nm in average, were utilized with a nanostructure cobalt based filler metal with 0.5 and 2 wt% using sonication with ultrasonic equipment at room temperature for 30 minutes and drying at 80 °C. The nanostructured materials were analyzed using Differential Scanning Calorimetry / Thermogravimetrics (DSC/TGA) using heating and cooling rates of 20 °C/min at 1400 °C as well as being inspected by scanning electron microscopy (SEM). The filler metals were deposited by PTA on heat treated H13 steel under a 20 g/min argon flow and a 17 cm/min feed rate. Weld beads were characterized by SEM and the tribological properties were evaluated by a pin on disk test.