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Abstract: Lanthanum magnesium hexaaluminate (LaMgAl11O19) powders were synthesized successfully at 1300°C for 4h by solid-state reaction, and LaMgAl11O19 ceramic was prepared at 1700°C for 6h by pressureless sintering. Phase composition, microstructure, mechanical and thermophysical properties of LaMgAl11O19 ceramic were investigated. Results show that the flexural strength and fracture toughness of LaMgAl11O19 ceramic are 353.3±12.5MPa and 4.60±0.46MPam1/2. Young''s Modulus and Poisson ratio is 295GPa and 0.23, respectively. The linear thermal expansion coefficient of LaMgAl11O19 ceramic from 473K to 1473K is 9.17×10−6/K, and thermal conductivity at 1273K is 2.55W/mK. [Copyright &y& Elsevier]

A novel metal–ceramic matrix composite of Fe/Mo–Sialon was prepared by hot-pressed sintering. The phase composition and mechanical properties of the ceramic were studied. The results showed that main phases in Fe/Mo–Sialon contained β-Sialon, Mo, FeMo and FeSi2. The flexural strength initially increased, and then decreased with increasing FeMo70 alloy addition. The hardness decreased gradually with increasing FeMo70 alloy addition. With a flexural strength of 426.7MPa and a Vickers hardness (HV0.5) of 19.3GPa, Fe/Mo–Sialon ceramic with 19.3wt.% FeMo70 added exhibited the best mechanical properties. [Copyright &y& Elsevier]