resumo
Tungsten carbide with microsized particle powders are commonly used embedded in a tough binder metal. The application of these composites is not limited to cutting tools, WC based material has been increasingly used in gaskets and other mechanical parts with complex geometries. Consequently, additive manufacturing processes as Selective Laser Sintering (SLS) might be the solution to overcome some of the manufacturing problems. However, the use of SLS leads to resolve the problems resulting from difference of physical properties between tungsten carbide and the metallic binder, such as laser absorbance and thermal conductivity. In this work, an original approach of powder surface modification was considered to prepare WCmetal composite powders and overcome these constraints, consisting on the sputter-coating of the WC particle surfaces with a nanocrystalline thin film of metallic binder material (stainless steel). The coating improves the thermal behavior and rheology of the WC particles and, at the same time, ensures a binder homogenous distribution. The feasibility of the SLS technology as manufacturing process for WC powder sputter-coated with 13 wt% stainless steel AISI 304L was explored with different laser power and scanning speed parameters. The SLS layers were characterized regarding elemental distribution, phase composition and morphology, and the results are discussed emphasizing the role of the coating on the consolidation process. (C) 2017 Elsevier B.V. All rights reserved.
palavras-chave
TUNGSTEN CARBIDE POWDERS; STAINLESS-STEEL; LASER; MICROSTRUCTURE; PARTICLES; COBALT; SLS
categoria
Chemistry; Materials Science; Physics
autores
Cavaleiro, AJ; Fernandes, CM; Farinha, AR; Gestel, CV; Jhabvala, J; Boillat, E; Senos, AMR; Vieira, MT
nossos autores
Ana Maria de Oliveira e Rocha Senos
Colaborador
Cristina Maria da Silva Fernandes
ColaboradorGrupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
agradecimentos
This research was supported by FEDER funds through the program COMPETE Programa Operacional Factores de Competitividade and by national funds through FCT - Fundacao para a Ciencia e a Tecnologia under the projects PEst-C/EME/UI0285/2013(CEMUC) and FCOMP-01-0124-FERDER-037271 (CICECO) and by FEDER/FCT funds through the Grants SFRH/BD/68354/2010 and SFRH/BPD/43402/2008. This research was also sponsored by FEDER funds through the program COMPETE Programa Operacional Factores de Competitividade under project CENTRO-07-0224-FEDER-002001 "MT4MOBI - Materials and Technologies for Greener Manufacturing & Products Applied to Mobility" and SciTech Science and Technology for Competitive and Sustainable Industries, R&D project co-financed by Programa Operacional Regional do Norte ("NORTE2020").