高熵过渡金属二硼化物的高温高压合成

High-Temperature and High-Pressure Synthesis of High-Entropy Transition Metal Diborides

高熵过渡金属二硼化物因其优异的力学性能及热物理性能受到了人们的广泛关注。然而,过去通过高温固相反应合成的效率较低。为此,通过高温高压固相反应,在5.5 GPa、2300℃的温压条件下合成了以VB_(2)、NbB_(2)、TaB_(2)为基底的6类高熵过渡金属二硼化物。高压提高了高温下的固相反应效率,促进了高熵过渡金属二硼化物的合成。通过X射线衍射和能量色散X射线光谱仪表征并确认了6类高熵过渡金属二硼化物均由纯相组成,不存在氧化物杂质或第二相,且元素分布均匀,不存在元素偏析,证明了高温高压合成高熵过渡金属二硼化物的有效性和普适性。相,且元素分布均匀,不存在元素偏析,证明了高温高压合成高熵过渡金属二硼化物的有效性和普适性。

High-entropy transition metal diborides have been extensively studied due to their high mechanical and thermodynamic properties.However,the conventional synthesis methods of these materials are inefficient.In this paper,we synthesized six types of high-entropy transition metal diborides based on VB_(2),NbB_(2),and TaB_(2)by high-temperature and high-pressure solid-state reactions at 5.5 GPa and 2300°C.The high pressure promoted the efficiency of solid-state reaction and facilitated the synthesis of high-entropy transition metal diborides.The X-ray diffraction and energy dispersive X-ray spectroscopy results have been confirmed that the six types of high-entropy transition metal diborides possessed pure phase compositions without oxide impurities or second phases,and exhibited uniform elemental distribution without elemental segregation.These results demonstrate that the synthesis of high-entropy transition metal diborides by using high-temperature and high-pressure solid-state reaction method is effectiveness and practicality.