Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Coaxial Laser Cladding of Tribaloy T800™ Alloy
Submission Author:
Daiana Aparecida Kruchelski da Silva , PR , Brazil
Co-Authors:
Daiana Aparecida Kruchelski da Silva, Robson Reis da Silva, Moises Teixeira, ALEX PIZZATTO, Adriano Scheid
Presenter: Daiana Aparecida Kruchelski da Silva
doi://10.26678/ABCM.COBEM2023.COB2023-1021
Abstract
Laser cladding has been considered in many engineering areas as an attractive option to withstand the wear and corrosion of materials. A recent study reported that nearly 23% of global energy is consumed to overwhelm friction and to remanufacture worn components of industrial machines and equipment. Thus, the development of coatings to obtain lower friction coefficients or even to withstand the wear and corrosion degradation of components seems to fit well with sustainability claims, draining the scientific community´s attention in the field of surface engineering. In this context, the CoCrMoSi alloy system - commercially known as Tribaloy™ – has shown promising performance in metal-to-metal contact wear and under corrosion-wear degradation. Also, due to the extremely refined microstructures, excellent wear behavior is associated with Laser cladding. However, the high heating/cooling rates often can cause coating microcracks due to the thermal gradients and stresses, hindering the prompt deposition of many alloys. As a step of weldment qualification, this work aims to investigate the effect of heat input on the microstructure and hardness of CoCrMoSi (Tribaloy T800™) alloy coatings. Single and multi-beads were deposited with 2.0, 2.5, and 3.0 kW laser powers, inspected through non-destructive testing to evaluate cracking, and characterized concerning bead geometry, dilution, microstructure, and hardness. The microstructure of single-beads is comprised of primary intermetallic Laves phase dispersed in a cobalt solid solution matrix. Multi-beads showed a similar microstructure for 2.0 kW laser power, whilst in higher laser powers (2.5- and 3.0- kW) the microstructure was altered to a full lamellar eutectic. Multi-bead coatings showed a trend to reduce the cracking intensity as a higher laser power is adopted, probably due to a conjugated effect of larger pre-heating leading to slightly lower cooling rates, and reduction of the Laves phase volume fraction. Irrespective of the microstructure changes, coatings showed an average hardness higher than 800 HV. This work highlighted the importance of the qualification step and showed how critical heat input is on the coatings’ features.
Keywords
LASER Cladding, CoCrMoSi alloy, Tribaloy T800™, Dilution, Microstructure, hardness
