(南昌大學(xué) 機(jī)電工程學(xué)院，南昌 330031)
摘 要: 將Al粉、Zn粉、碳納米管(CNTs)混合料按照質(zhì)量比為3׃1׃X(X=0，0.5，1.0，1.5)壓塊，并用鐘罩壓入法將這些預(yù)先制備的壓塊加入到合金熔體中制備AZ31/CNTs復(fù)合材料。測試該復(fù)合材料的力學(xué)性能，利用掃描電子顯微鏡(SEM)、能譜分析儀(EDS)、X射線衍射儀和光學(xué)顯微鏡對AZ31/CNTs復(fù)合材料的金相試樣、斷口形貌進(jìn)行表征和分析。結(jié)果表明：鐘罩壓塊法可以有效地將碳納米管分散到鎂合金熔體中；CNTs對AZ31鎂合金的力學(xué)性能有較強(qiáng)的增強(qiáng)效果，與本研究中的鑄造AZ31合金相比，AZ31/CNTs復(fù)合材料的最大抗拉強(qiáng)度和伸長率分別提高41.3%和119.4%，彈性模量和顯微硬度分別提高67.8%和66.9%；CNTs對AZ31鎂合金基體晶粒的細(xì)化作用顯著，與鎂基體界面結(jié)合較好；復(fù)合材料試樣斷口形貌由韌窩和撕裂棱組成，呈現(xiàn)準(zhǔn)解理斷裂特征。
關(guān)鍵字: AZ31鎂合金；碳納米管；預(yù)制塊；復(fù)合材料；力學(xué)性能
prepared by adding CNTs block with plunger
（School of Mechatronics Engineering, Nanchang University, Nanchang 330031, China）
Abstract:Precast blocks were prepared with powders of Al, Zn and carbon nanotubes with mass ratio of 3׃1׃X(X=0, 0.5, 1.0, 1.5), and then the carbon nanotubes AZ31 composites were produced by immersing the precast block into the alloy melt by adding CNTs block with plunger. The mechanical properties of the as-cast AZ31 alloy based composites (AZ31/CNTs) were tested and their microstructures and fracture morphology were observed by metalloscopy, scanning electron microscopy (SEM), energy depressive spectroscopy (EDS) and X-ray diffractometry. The results show that the CNTs are dispersed effectively by bell jar immersing precast block casting. The maximal tensile strength and the elongation of the AZ31/CNTs composites are enhanced by 41.3% and 119.4%, respectively, and the elastic modulus and micro-hardness are also raised by 67.8% and 66.9%, respectively, when compared with those of the as-cast AZ31 Mg alloys. The CNTs can greatly refine the grains of the composites, playing a good role in reinforcing the matrixes of AZ31 Mg alloy. The fracture sections of the composites mainly consist of dimples and prisms, which demonstrates quasi- cleavage fracture modes.
Key words: AZ31 Mg alloy; carbon nanotubes; precast block; composite; mechanical properties
