摘要
针对原位自生Al2O3增强钼基复合材料晶粒较大的问题,采用溶胶-凝胶与高能球磨相结合的方法细化复合材料晶粒,并利用SEM、XRD对不同球磨工艺所制备Al2O3/Mo复合粉末及复合材料的组织进行了观察和分析。结果表明:随着球磨时间的延长,Al2O3/Mo复合粉末颗粒由球状变为层片状再成为细小的球状,颗粒大小由约1.5μm细化为约500nm,其中的钼晶粒不断细化;高球料比所得粉末的分散性和破碎细化程度较好;转速提高使得粉末颗粒的尺寸均匀程度降低,且伴有结块现象,不利于粉末的细化。在球料比5∶1、转速300r/min、球磨时间60h条件下获得的复合粉末,经压坯烧结可制备出Al2O3颗粒为纳米级的钼基复合材料。
In view of coarse grains of in-situ synthesized Al2O3 particle enhanced molybdenum-based composite material, the composite grains are refined together with sol-gel method and high energy ball milling technique. The microstructure of Al2O3/Mo composite powder and composite material prepared by different milling processes were observed and analyzed by XRD and SEM. The results show that with milling time increasing,the appearance of the composite powder particles changes from ball shape to lamel shape and then to small ball shape,particle size changes from around 1.5 μm to 500 nm, and the molybdenum grains are refined gradually. Both dispersibility and refinement degree of the powder prepared at high ball/ powder weight ratio are better. Improved milling speed results in reduced uniformity of powder particle size and powder agglomeration, hindering powder refinement. Nanoscale Al2O3 enhanced molybdenum-based composite material can be obtained by pressing and sintering and with the composite powder prepared under the conditions of ball/powder weight ratio 5 ： 1,rotation speed 300 r/min and milling time 60 h.
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2012年第4期45-49,共5页
Rare Metals and Cemented Carbides
基金
国家自然科学基金资助项目(50972039)
