In recent years, with the rapid development of aerospace technology and leap-forward progress, ultra-high-speed aircraft, aerospace aircraft, and reusable trans-atmosphere aircraft have become hotspots in various countries’ research, and their supersonic and reusable service characteristics. There is an increasing demand for the comprehensive properties of materials for critical hot end components. Hafnium boride (HfB2) is a member of the ultra-high temperature materials family. Due to its high melting point (3380 ° C), excellent thermochemical stability and excellent physical properties, including high modulus of elasticity, high hardness and good thermal shock resistance, it can maintain high strength at high temperatures. The most promising candidate material. The purity and particle size of the raw materials are very important for the sintering properties and high temperature properties of ultra-high temperature materials. Therefore, the production of high purity and ultrafine ceramic powder is a prerequisite for the preparation of high performance ceramic materials. The raw materials were ball milled in absolute ethanol for 24 h according to the ratio; then dried and pressed; the obtained sample was raised to the required temperature at a heating rate of 10 ° C per minute in a Multi-5000 multi-functional sintering furnace, and the temperature was kept 1 ～ 2 h. Finally, the obtained sample was ground into a powder to obtain a lanthanum boride powder. The phase of the obtained lanthanum boride powder was detected by a D8 ADVANCE X-ray diffractometer manufactured by BRUKER, Germany. The measurement conditions were as follows: Cu target, 2θ scanning range: 4° to 152°, angular accuracy: 2θ ≤ ± 0. 01°. The microstructure of the powder was observed and analyzed using a Sirion 200 thermal field emission scanning electron microscope manufactured by FEI of the Netherlands. The measurement conditions were as follows: Resolution: 1. 5 nm, accelerating voltage: 0. 2 to 30 kV.
Investigation on Synthesis of Hafnium Diboride Powder by Reductive Reaction