W-Al_2O_3复合粉末制备工艺研究  

Study on Preparation Process of W-Al_2O_3 Composite Powder

作　　者：赵阳[1] 魏世忠[2] 潘昆明[2] 单康宁[1] 姚丽莹[1] 宋向阳[1] 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471003 [2]河南科技大学耐磨材料工程技术研究中心,河南洛阳471003

出　　处：《稀有金属与硬质合金》2017年第3期25-30,共6页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金项目(U1504514);长江学者和创新团队发展计划项目(IRT1234);河南省科技攻关项目(152102410037)

摘　　要：采用溶胶凝胶法、共沸蒸馏法和水热合成法制备了Al_2O_3掺杂W粉末,并经煅烧以及两段氢气还原过程制成W-Al_2O_3复合粉末。通过SEM形貌观察以及XRD物相分析可知,由3种方法制备的Al_2O_3掺杂W粉末经过煅烧均得到了稳态单斜相WO_3和非稳态六方相WO_3;其中水热合成法制得粉末形貌较为规则,为均匀的小球状;经过一段氢气还原,WO_3被还原为低价态的WO_2和不饱和价态的WO_3-x;二段氢气还原后得到了细小的W-Al_2O_3复合粉末。采用溶胶凝胶法制备的W-Al_2O_3复合粉末,由于Al_2O_3包裹在W颗粒表面阻碍了后续被还原W原子的沉积,相较于其他两种方法细化作用更加明显,颗粒可达纳米级。Al2 O3-doped W powder was prepared by sol-gel, azeotropic distillation and hydrothermal synthesis to produce W-Al2 O3 composite powder by calcination and two-step H2 reduction. Based on XRD analysis and SEM observation, stable monoclinic WOa and metastable hexagonal WO3 were obtained by calcination of Al2 O3-doped W powder prepared with the above-mentioned three methods. The morphology of the powder prepared by hydrothermal synthesis is regular, uniform and spherical. WO3 is reduced to low-valence WO2 and unsaturated-valence WO3-x by the primary H2 reduction,and fine W-Al2 O3 composite powder is obtained by the secondary H2 reduction. Compared with the other two methods, sol-gel method has more obvious refinement effect and it can prepare W-Al2O3 composite powder with nanoscale particle size, since Al2 O3 coated on the surfaces of W particles inhibits the deposition of tungsten atom during subsequent reduction.

关 键 词：W-Al2O3复合粉末 溶胶凝胶法 共沸蒸馏 水热合成 煅烧 两段氢气还原 

分 类 号：TG146.411[一般工业技术—材料科学与工程]