Nickel Porous Compacts Obtained by Medium-Frequency Electrical Resistance Sintering

A commercially pure (c.p.) nickel powder was consolidated by Medium-Frequency Electrical Resistance Sintering (MF-ERS). In this consolidation technique, a pressure and the heat released by a high-intensity and low-voltage electrical current are concurrently applied to a metal powder mass. A nickel p...

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Detalhes bibliográficos
Autores: Ternero Fernández, Fátima, Sánchez Caballero, Eduardo, Astacio López, Raquel, Cintas Físico, Jesús, Montes Martos, Juan Manuel
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Recursos:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/99047
Acesso em linha:https://hdl.handle.net/11441/99047
https://doi.org/10.3390/ma13092131
Access Level:acceso abierto
Palavra-chave:Electrical resistance sintering
Electrical consolidation
MF-ERS
ECAS
FAST
Hot pressing
Sintering
Nickel powder
Powder metallurgy
Descrição
Resumo:A commercially pure (c.p.) nickel powder was consolidated by Medium-Frequency Electrical Resistance Sintering (MF-ERS). In this consolidation technique, a pressure and the heat released by a high-intensity and low-voltage electrical current are concurrently applied to a metal powder mass. A nickel powder with a high tap porosity (86%) and a low applied pressure (only 100 MPa) is chosen in order to be able to obtain compacts with different levels of porosity, to facilitate the study of the porosity influence on the compact properties. The influence of current intensity and heating time on the global porosity values, the porosity and microhardness distribution, and the electrical conductivity of the sintered compacts is studied. The properties of the compacts consolidated by MF-ERS are compared with the results obtained by the conventional powder metallurgy route, consisting of cold pressing and furnace sintering. A universal equation to describe the porosity influence on all the analyzed properties of powder aggregates and sintered compacts is proposed and validated.