Author/Authors :
Karamian، .E نويسنده Department of Materials Engineering, Najafabad Branch, Islamic Azad University, IAUN, P.O.Box 517, Isfahan, Iran , , Bataille، .A نويسنده UMET, Unité Matériaux et Transformations, UMR CNRS 8207, University of Lille Science and Technology, F-59655 Villeneuve d’Ascq Cedex, France , , Abdollah، .S نويسنده Department of Materials Engineering, Najafabad Branch, Islamic Azad University, IAUN, P.O.Box 517, Isfahan, Iran ,
Abstract :
Spark plasma sintering (SPS) method, as plasma activated sintering, is a method applicable for rapid sintering of
metals and ceramics. Owing to the advantage of rapid heating, the alumina ceramics obtained by SPS have a grain
size and density comparable to those of hot pressed ones. The increase of densification rate may be related to
some difference in ion transport characteristics. This study describes creep behavior and deformation mechanisms
of alumina based materials densified by SPS, and somewhat comparison is made with hot pressing (HP) at high
temperature. Pure alumina was densified by SPS at 65 MPa (1200 ?C) and 45 MPa (1400 ?C) by HP. The grain size
of the alumina HPed was twice more than the grain size of the sample SPSed. Compressive creep tests in air were
performed at different true stresses up to100 MPa and different temperatures (1200 ?C-1400 ?C). The grain growth
was found to be more active during creep of SPS alumina than the creep of HP alumina. Generally, the fineness
of SPS materials microstructure speeded up all processes related to diffusion. The ratio of dynamic to static grain
growth in SPSed samples was twice more than HPed samples during creep test.
