| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1605336 | Journal of Alloys and Compounds | 2016 | 6 Pages |
•The effects of sintering parameters on the microstructure of magnesium aluminate spinel are investigated.•By using single-step sintering method, the densification kinetics of MAS is different from grain growth kinetics.•A MAS material with a high relative density and a homogeneous microstructure consisting of small grains is achieved under optimum two-step sintering.•The flexure strength and Vickers hardness of the MAS sintered at optimum two-step sintering are improved.
The effects of sintering parameters, first and second step sintering temperatures (T1 and T2, respectively), on the microstructure of magnesium aluminate spinel (MAS) were investigated. A single-step sintering (SSS) method was used to determine the appropriate temperatures for the first step. Different two-step sintering (TSS) regimes were used to investigate the effect of second step sintering temperatures on densification behavior and grain growth. The results show that, by using SSS method, the densification kinetics of MAS is different from grain growth kinetics. A MAS material with a high relative density of 96.17% and a homogeneous microstructure consisting of small grains (680 nm) is achieved under optimum TSS conditions (T1 = 1650 °C/0 h and T2 = 1550 °C/10 h). Compared with conventional specimen, the bending strength (240 MPa) and Vickers hardness (11.05 GPa) of the sintered samples fabricated under optimum TSS increased by 54.8% and 52.2%, respectively.
