(1. 河南科技大学 材料科学与工程学院，洛阳 471003；
2. 河南科技大学 河南省耐磨材料工程技术研究中心，洛阳 471003)
摘 要: 对Mo和Al2O3/Mo纳米粉末进行模压成形，研究纯Mo和Al2O3/Mo压坯在1 700~2 000 ℃温度范围内的等温烧结过程，并结合烧结模型分析材料烧结过程中的动力学；利用SEM和TEM分析复合材料的显微组织。结果表明：压坯密度与Al2O3的加入量有关，高温烧结时Al2O3/Mo复合材料的致密度高于纯Mo的致密度；在Al2O3/Mo复合材料烧结过程中，烧结机制既有体积扩散又有晶界扩散，且随着Al2O3含量的增加，晶界扩散趋势明显；纯Mo和Al2O3体积分数为5%、10%和15% Al2O3/Mo复合材料的烧结激活能分别为254.24、234.04、221.40和164.37 kJ/mol；Al2O3的加入可促进晶粒的均匀化和组织的细化。
关键字: Al2O3；Mo；纳米粉末；烧结；动力学；激活能
（1. College of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, China;
2. Henan Engineering Research Center for Wear of Materials, Henan University of Science and Technology,
Luoyang 471003, China）
Abstract:By molding formation, the isothermal sintering processes of pure Mo and Al2O3/Mo green compact were investigated in the temperature range of 1 700-2 000 ℃. And combined with sintering model, the sintering kinetics was studied. The microstructures of the composites were analyzed by SEM and TEM. The results show that the green compact density and the adding amount of Al2O3 are related, and the composite density is higher than that of pure Mo in high temperature sintering process. During Al2O3/Mo composite sintering process, the sintering mechanism is proved to contain volume diffusion and grain boundary diffusion, and with the increase of Al2O3 content, the latter trend is obvious. The sintering activation energies of pure Mo and Al2O3 composites with volume fractions of 5%, 10% and 15% are 254.24, 234.04, 221.40 and 164.37 kJ/mol, respectively. The addition of Al2O3 can promote the uniformity and refining for the grains.
Key words: Al2O3; Mo; nanometer powder; sintering; kinetics; activation energy
