The spark plasma sintering （SPS） was applied to prepare α-Si3 N4 ceramics of different densities with magnesia, silicon dioxide, alumina as the sintering aids. The mechanism of liquid phase sintering （LPS） wus d...The spark plasma sintering （SPS） was applied to prepare α-Si3 N4 ceramics of different densities with magnesia, silicon dioxide, alumina as the sintering aids. The mechanism of liquid phase sintering （LPS） wus discussed and the factors influencing the density of the prepared samples were analyzed. The dielectric constant of sintered samples was tested. The experimental results show that the density can be controlled from 2.48 g/ cm^3 to 3.09 g/ cm^3 while the content of the sintering aids and the sintering temperature alter and the dielectric constant is closely dependent on the density of obtained samples.展开更多
Silicon carbide (SiC) composites were prepared by hot-press sintering from α-SiC starting powders with BaAl2Si2O8 (BAS). The effects of additives on densification, microstructure, flexural strength, and fracture beha...Silicon carbide (SiC) composites were prepared by hot-press sintering from α-SiC starting powders with BaAl2Si2O8 (BAS). The effects of additives on densification, microstructure, flexural strength, and fracture behavior of the liquid phase sintered (LPS) SiC composites were investigated. The results show that the served BAS effectively promotes the densification of SiC composites. The flexural strength and fracture toughness of the SiC composites can reach a maximum value of 454 MPa and 5.1 MPa·m1/2, respectively, for 40% (w/w) BAS/SiC composites. SiC grain pullout, crack deflection, and crack bridging were main toughening mechanisms for the sintered composites.展开更多
The heat treatment microstructures and XRD patterns of the Mg-8Gd-5Y-2Zn-0.5Zr(wt.%) alloy in the absence and presence of a 10T high magnetic field have been investigated.The investigations show that the grains of α-...The heat treatment microstructures and XRD patterns of the Mg-8Gd-5Y-2Zn-0.5Zr(wt.%) alloy in the absence and presence of a 10T high magnetic field have been investigated.The investigations show that the grains of α-Mg demonstrate a preferred orientation due to the magnetic driving force.In addition,high magnetic fields can promote the growth of the long period ordered structure(LPS) phase to the grain interior.And the corresponding mechanisms are also discussed in this article.展开更多
文摘The spark plasma sintering （SPS） was applied to prepare α-Si3 N4 ceramics of different densities with magnesia, silicon dioxide, alumina as the sintering aids. The mechanism of liquid phase sintering （LPS） wus discussed and the factors influencing the density of the prepared samples were analyzed. The dielectric constant of sintered samples was tested. The experimental results show that the density can be controlled from 2.48 g/ cm^3 to 3.09 g/ cm^3 while the content of the sintering aids and the sintering temperature alter and the dielectric constant is closely dependent on the density of obtained samples.
文摘Silicon carbide (SiC) composites were prepared by hot-press sintering from α-SiC starting powders with BaAl2Si2O8 (BAS). The effects of additives on densification, microstructure, flexural strength, and fracture behavior of the liquid phase sintered (LPS) SiC composites were investigated. The results show that the served BAS effectively promotes the densification of SiC composites. The flexural strength and fracture toughness of the SiC composites can reach a maximum value of 454 MPa and 5.1 MPa·m1/2, respectively, for 40% (w/w) BAS/SiC composites. SiC grain pullout, crack deflection, and crack bridging were main toughening mechanisms for the sintered composites.
基金Item Sponsored by the Fundamental Research Funds for the Central University[NO.DUT12JN02]
文摘The heat treatment microstructures and XRD patterns of the Mg-8Gd-5Y-2Zn-0.5Zr(wt.%) alloy in the absence and presence of a 10T high magnetic field have been investigated.The investigations show that the grains of α-Mg demonstrate a preferred orientation due to the magnetic driving force.In addition,high magnetic fields can promote the growth of the long period ordered structure(LPS) phase to the grain interior.And the corresponding mechanisms are also discussed in this article.
