Co-based Superalloy (Stellite 6) Powder with Added Nanoparticles to be Molten by PTA

Abstract:

Nanotechnology is the domain of technological development and application of materials which go from 1 to 100 nm in at least one of their dimensions. The use of nanoparticles in engineering focuses on the development of new materials with special properties, which can be used as filler materials in the welding field. In this context, this study contributes to the stage preceding the deposition of the weld beads. This work aims to insert, using the colloidal processing technique, ceramic nanoparticles (ZrO₂) into a Co-based superalloy (Stellite 6) and study the solidification of this “nanocomposite”. 4 filler materials in the shape of compacted cylinders were melted by PTA: Stellite 6 with added Fe carriers with ceramic nanoparticles (ZrO₂) (1%, 2.5% and 7.5% volume) and Stellite 6 without any additions. The molten materials were characterized through optical and scanning electron microscopy with field emission (SEM-FEG), XRD and Vickers microhardness. The results show that the colloidal processing technique was effective in adhering the ZrO₂ nanoparticles to the carrier Fe particles, which were mixed with Stellite 6, as well as the relationship between microstructure refinement, phases and microhardness after PTA melting.

Key-words:
Nanoparticle carriers; Welding; Superalloys; Solidification; CoCrWC alloy