(American Institute of Physics Inc., 2015-03) Caballero Sánchez, Eduardo; Cintas Físico, Jesús; Gómez Cuevas, Francisco de Paula; Montes Martos, Juan Manuel; Herrera García, Marta; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte
Aluminium powder was mechanically alloyed under ammonia gas flow for different
times (1-5 h) in order to produce a second-phase reinforcement, mainly by aluminium nitride
(AlN). After milling, powders were consolidated by cold uniaxial pressing and vacuum
sintering. A small amount of copper powder was added to the Al milled powder to improve its
sintering behavior. Hardness and indirect tensile test were carried out at room and high
temperature to evaluate the mechanical properties evolution. Results showed an remarkable
hardness increase with the second phases content, even at high temperature (up to 229 HB at 400
ºC). However, the high content of second phases of ceramic nature decreases the ductility,
resulting in low values of tensile strength (lower than 160 MPa).
