【摘要】 以金属锆粉(Zr)和六方氮化硼粉(h-BN)为原料,结合高能球磨和高温高压合成技术,制备出了ZrN-ZrB2纳米复合材料。利用X射线衍射、透射电镜和拉曼光谱等测试手段,对材料的结构和合成规律进行了研究。结果表明,高能球磨过程中只合成出了ZrNx,没有出现ZrB2,从N、B原子与Zr进行固态反应的热力学和动力学方面分析了原因。利用Zr与BN粉球磨10 h后的混料,在压力为5 GPa、温度为1 300℃的条件下,制备出了具有高致密度的ZrN-ZrB2纳米复合材料。其维氏显微硬度(17 GPa)、热膨胀系数(7.57×10-6℃-1)和电阻率-温度系数(8.846×10-4℃-1)等材料参数的测量结果表明,ZrN-ZrB2复合材料是一种集优良的力学、热学和电学性能于一体的纳米复合材料。更多还原

【Abstract】 Combining high-energy ball milling and high-pressure high-temperature technique,high-dense ZrN-ZrB2 nanocomposites have been synthesized using Zr and h-BN powders as raw materials.The structures of product materials were studied through X-ray diffraction,high resolution transmission electron microscopy and Raman spectroscopy measurements.The result showed that only ZrNx can be synthesized during mechanical alloying process,which can be explained by the thermodynamics and kinetics of reaction of Zr atoms with N and B atoms.ZrN-ZrB2 nanocomposites synthesized at 5 GPa and 1 300 ℃ using 10 h ball-milled powder mixture show excellent mechanical and electrical properties.The microhardness,thermal expansion coefficient and thermal coefficient of resistivity of ZrN-ZrB2 composites are 17 GPa,7.57×10-6 ℃-1 and 8.846×10-4 ℃-1,respectively.更多还原