(1. 河南科技大學(xué) 材料科學(xué)與工程學(xué)院，洛陽 471003；
2. 河南科技大學(xué) 河南省耐磨材料工程技術(shù)研究中心，洛陽 471003)
摘 要: 對Mo和Al2O3/Mo納米粉末進(jìn)行模壓成形，研究純Mo和Al2O3/Mo壓坯在1 700~2 000 ℃溫度范圍內(nèi)的等溫?zé)Y(jié)過程，并結(jié)合燒結(jié)模型分析材料燒結(jié)過程中的動力學(xué)；利用SEM和TEM分析復(fù)合材料的顯微組織。結(jié)果表明：壓坯密度與Al2O3的加入量有關(guān)，高溫?zé)Y(jié)時Al2O3/Mo復(fù)合材料的致密度高于純Mo的致密度；在Al2O3/Mo復(fù)合材料燒結(jié)過程中，燒結(jié)機(jī)制既有體積擴(kuò)散又有晶界擴(kuò)散，且隨著Al2O3含量的增加，晶界擴(kuò)散趨勢明顯；純Mo和Al2O3體積分?jǐn)?shù)為5%、10%和15% Al2O3/Mo復(fù)合材料的燒結(jié)激活能分別為254.24、234.04、221.40和164.37 kJ/mol；Al2O3的加入可促進(jìn)晶粒的均勻化和組織的細(xì)化。
關(guān)鍵字: Al2O3；Mo；納米粉末；燒結(jié)；動力學(xué)；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
