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Zirconium diboride is widely applied to high-temperature materials, but it is easily oxidized at high temperature. To increase the oxidation resistance of zirconium diboride at high temperature, the A1(OH)3–Y(OH)3 is coated on the ZrB2 surface to prepare A1(OH)3–Y(OH)3/ZrB2 composite particles. In this paper, the effect of coating content on the properties of A1(OH)3–Y(OH)3/ZrB2 composite particles is investigated. It is analyzed that the particle size and particle size distribution of A1(OH)3–Y(OH)3/ZrB2 composite particles is increased with the coating content. The dispersion of ZrB2 particles is largely increased with the coating content of 0%–20%; the dispersion of ZrB2 particles is similar when the coating content is from 20% to 30%. The oxidation resistance ratio of the ZrB2 particles with 30% coating content is the best than that of other conditions—it is about three times more than that of the original ZrB2 particles.

Although Zirconium diboride (ZrB2) is a desirable combination with some good properties, it is easily oxidized in the high-temperature air to impact high-temperature properties, which dwindles the applied range. In order to decrease oxidization and improve the high-temperature properties of ZrB2, the surface of ZrB2 is coated with Al(OH)3–Y(OH)3 to synthesize Al(OH)3–Y(OH)3/ZrB2 composite particles. In this paper, the conditions of synthesizing Al(OH)3–Y(OH)3/ZrB2 composite particles by the co-precipitation method are investigated. Al(OH)3–Y(OH)3/ZrB2 composite particles are synthesized under different conditions, but the conditions of synthesizing Al(OH)3–Y(OH)3/ZrB2 composite particles with the better coating quality require pH = 9, the appropriate concentration (Al3+ = 0.017 mol/L, Y3+ = 0.01 mol/L) of composite solution, reaction time of 60 min, titration speed of 0.05 ml/s, using the dispersant in the ZrB2 suspension and the ultrasonic dispersion, respectively.

In order to decrease the oxidization and improve the strength of ZrB2 at high temperature, the surface of ZrB2 was coated with Al(OH)3 and Y(OH)3 to synthesize Al(OH)3-Y(OH)3-ZrB2 composite particles. Through TEM, EPMA and SEM analysis, when pH was about 9, Al(OH)3-Y(OH)3-ZrB2 composite particles were successfully synthesized by co-precipitation methods. The coating layer was about 25 nm, which has compaction and conformability. Dispersibility of coated ZrB2 with Al(OH)3 and Y(OH)3 particles were very good. Synthesis of Al(OH)3-Y(OH)3-ZrB2 composite powder will lay the foundation for preparing high-performance YAG/ZrB2 and Al2O3-YAG/ZrB2 multiphase ceramic materials.

To decrease the oxidation and improve the strength of ZrB2 at high temperatures, the surface of ZrB2 is coated with Al(OH)3 and Y(OH)3, which results in the production of Al(OH)3‐Y(OH)3‐ZrB2 composite particles. The pH value through analysis of theory and calculation must be greater than 8.3 provided that Al(NO3)3 and Y(NO3)3 both reached the saturated concentration of heterogeneous nucleation or homogeneous nucleation to co‐precipitation of Y3+ and Al3+ precursors on the surface of ZrB2 particles. When pH is 9, Al(OH)3‐Y(OH)3‐ZrB2 composite particles are synthesized successfully and the best coating quality with Al(OH)3 and Y(OH)3 by co‐precipitation method, which established the foundation for preparing high‐performance YAG/ZrB2 and Al2O3‐YAG/ZrB2 multiphase ceramic materials.

A composite complex salt—(NH4)1.91(In0.91Sn0.09)Cl5· ?H2O—was synthesized from the starting materials InCl3, HCl, SnCl4 and NH4HCO3. The hydrolyzate of (NH4)1.91(In0.91Sn0.09)Cl5· ?H2O were prepared under the condition of room temperature and fiercely stirring, using NH4HCO3 as precipitator and polyethylene glycol as disperser. Indium-tin oxide (ITO) nanoparticles were prepared by calcined the hydrolyzate at 700°C for 1 h in air. The prepared ITO particles were characterized via X-ray diffractometry, scanning electron microscopy and laser particle size analyzer. The results indicated the average crystalline grain size, a primary particle size and an average aggregation size of prepared ITO powders is 34.6 nm, 50–100 nm and of 107 nm, respectively.