Abstract
Ti–Ni–ZrO2 composites were prepared by spark plasma sintering (SPS). The effect of ZrO2
content on the densification, microstructure and microhardness properties of the
composites were investigated. Samples were characterized by SEM, EDS and XRD
analyses. Noticeably, SPS process under the sintering conditions was achieved at a
sintering temperature of 950 ºC, for 10 min holding time, at 100 °C/min of heating rate and
at an applied pressure of 50 MPa. This resulted in maximum densification of the powder
compact and the formation of a distinguishable spherical globules rich in Ni surrounding
the retained Ti. Gradient composition distribution of ZrO2 at the grain boundaries resulted
into pinning effect of the grain growth. As the ZrO2 content increased from 5 to 10 vol.%,
it was accompanied by a significant increase in hardness values of the sintered composites
from 480 to 713 HV.