An investigation on the formation mechanism of nano ZrB2 powder by a magnesiothermic reaction

Abstract

Nanocrystalline zirconium diboride (ZrB 2 ) powder was produced by magnesiothermic reduction in the Mg/ZrO 2 /B 2 O 3 system. In this study, high-energy ball milling was used to generate the essential conditions to induce a mechanically induced self-sustaining reaction (MSR). The ignition time for ZrB 2 formation was found to be approximately 6 minutes. The mechanism for the formation of ZrB 2 in this system was determined by studying the relevant sub-reactions, the effect of stoichiometry, and the thermal behavior of the system.

In situ synthesis of NbB2–NbC composite powders by milling-assisted carbothermal reduction of oxide raw materials

“…3(b)). These two low-temperature endotherms are also consistent with those in the DSC scans of B 2 O 3 -containing powder blends reported by the previous studies [40,41]. As observed from Fig.…”

“…3(a) and (b) are the DSC and TG scans, respectively, of the as-blended powders and those milled for 1, 3 and 5 h. The DSC scans show small endothermic peaks in the vicinity of 90 and 190°C, corresponding to the release of humidity and the vapourization of water that is adsorbed to the B 2 O 3 ( Fig. 2(b)) [40,41]. These endotherms account for a powder weight loss of approximately 10% up to 200°C (Fig.…”

Mechanical and ablation properties of laminated ZrB2–SiC/BN ceramics

“…UHTCs have recently attracted significant research interest because of potential candidates for thermal protection systems (TPSs) of hypersonic aerospace vehicles and reusable atmospheric re-entry vehicles [5][6][7][8][9]. Among the UHTCs, ZrB 2 has the lowest theoretical density (6.09 g/cm 3 ) and high thermal conductivity, which is considered as one of the most attractive candidates for high temperature structural applications, including atmospheric re-entry, hypersonic flight, and rocket propulsion [10][11][12][13][14][15]. However, its intrinsic characteristics such as low fracture toughness, poor thermal shock resistance and poor sinterability, limit its applications [16,17].…”

Mechanochemical Synthesis of High Crystalline Cerium Hexaboride Nanoparticles from CeO2‐B2O3‐Mg Ternary System

“…This temperature is too low for the reduction of CeO 2 . 22 Low intensity of this peak indicates that this reaction didn't occur completely. On the other hand, increasing the temperature to 1100°C had no effect on DTA curve.…”