摘要
采用高能球磨法制备Al2O3/Cu复合粉末,通过X射线衍射仪(XRD)和扫描电镜(SEM)研究高能球磨时间对复合粉末的物相、晶粒尺寸和表面形貌的影响。结果表明,随球磨时间的增加,基体Cu的晶粒不断被细化,在球磨初期,晶粒尺寸减小很快,当晶粒尺寸小于20 nm时,细化速率变缓而趋于稳定;Cu颗粒形貌由树枝状变为层状,并向椭球体转变;纳米Al2O3颗粒逐渐嵌入Cu颗粒体内,且分散均匀,从而获得纳米Al2O3颗粒弥散分布的Cu基复合粉末。并探讨了高能球磨对放电等离子体烧结Al2O3/Cu复合材料导电性能和力学性能的影响,研究认为高能球磨可以促进基体的晶界强化和弥散强化,而晶界的增加并不会导致电阻率的显著增大,影响电阻率的主要因素为Al2O3的体积分数、孔隙和杂质的固溶。
Al2O3/Cu composite powder was obtained by high-energy milling. Phase composition, crystalline size and micrograpb were analyzed by X-ray diffraction and scanning electron microscope. The results show that crystalline size of copper decreases rapidly at the beginning milling and slows down with increasing the milling time. The shape of the Cu particles changes from dendrite to lamellar and then eUipsoidal gradually. Al2O3 nanoparticles tumble into the Cu particles gradually and spread out very well; finally the Al2O3 nanoparticles dispersed strengthened, strengthened copper matrix composite powder is obtained. The effect of the high-energy milling on the electrical resistivity and mechanical properties of the spark plasma sintered Al2O3/Cu composite materials was analyzed, and the results show that the high-energy milling can promote grain-boundary hardening and dispersion strengthening. The electrical resistivity won＇t increase significantly due to grain refinement. Indeed, the dominant factors affecting electrical resistivity are Al2O3 volume fraction, porosity and impurity＇s solid solubility.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2013年第2期259-264,共6页
Materials Science and Engineering of Powder Metallurgy
基金
重点实验室基金资助项目(9140C850201110C85)
XX关键技术(51326020202)
