復(fù)合材料的顯微組織
(南昌大學(xué) 先進(jìn)成形制造及模具研究所，南昌 330031)
摘 要: 采用高能超聲方法制備納米SiC顆粒增強(qiáng)AZ61鎂基復(fù)合材料，通過SEM和XRD技術(shù)對(duì)復(fù)合材料的微觀組織和成分進(jìn)行研究與分析。在Lennard-Jones勢(shì)函數(shù)的基礎(chǔ)上對(duì)超聲分散納米顆粒進(jìn)行了理論探討。結(jié)果表明：在超聲作用下，質(zhì)量分?jǐn)?shù)為1%的納米SiC顆粒在AZ61鎂合金中得到彌散分布；顆粒之間存在的范德華力使得顆粒連接在一起，范德華力與顆粒半徑和顆粒間距離的關(guān)系表明：直徑為100 nm的SiC顆粒之間最大的范德華力約為135 nN，分散團(tuán)聚納米顆粒的最小壓強(qiáng)約為17.2 MPa。
關(guān)鍵字: AZ61鎂合金；納米SiC；超聲振動(dòng)；顯微組織
（Institute of Advanced Forming & Manufacturing and Die & Mold, Nanchang University, Nanchang 330031, China）
Abstract: SiC nanoparticles reinforced AZ61 magnesium composites were fabricated by ultrasonic method. The microstructure and components of the composite were investigated by scanning electron microscopy (SEM) and XRD. Based on the Lennard-Jones potential function, the theory of dispersion nanoparticles by ultrasonic were also discussed. The results show that 1.0% (mass fraction) SiC nanoparticles can be dispersed very well in AZ61 magnesium matrix by ultrasonic dispersion. The particles are joined by van der Waals force. The relationships among van der Waals force, the radius and the distance between particles show that the maximal van der Waals force is approximately 135 nN between SiC nanoparticles with diameter of 100 nm. The minimal pressure to separate the agglomeration nanoparticles is approximately 17.2 MPa.
Key words: AZ61 magnesium alloy; SiC nanoparticles; ultrasonic method; microstructure
