影響及機(jī)制
(江蘇大學(xué) 材料科學(xué)與工程學(xué)院，鎮(zhèn)江 212013)
摘 要: 以Al-K2TiF6為反應(yīng)體系，采用熔體反應(yīng)法，在高能超聲場下原位合成Al3Ti/6070復(fù)合材料。采用XRD、SEM、EDS等手段研究不同超聲參數(shù)如超聲時(shí)間和超聲強(qiáng)度對Al3Ti/6070復(fù)合材料增強(qiáng)體形貌及尺寸的影響。建立了超聲作用下熔體中顆粒行為模型，并對其機(jī)制進(jìn)行了探討。結(jié)果表明：在一定的超聲強(qiáng)度下(0.66 kW/cm2)，顆粒尺寸隨超聲作用時(shí)間的延長(1~7 min)先減小后增大，當(dāng)作用時(shí)間為3 min時(shí)，顆粒最細(xì)小，尺寸為1~2 μm，形貌主要為小塊狀或短棒狀；當(dāng)超聲作用時(shí)間大于3 min時(shí)，顆粒數(shù)量隨時(shí)間增加而急劇減少；在相同的超聲作用時(shí)間(3 min)下，顆粒尺寸隨超聲強(qiáng)度的增加而減小，當(dāng)超聲強(qiáng)度為0.82 kW/cm2時(shí)，顆粒尺寸為0.5~1 μm，顆粒形貌主要為小塊狀或粒狀，當(dāng)超聲功率大于0.82 kW/cm2時(shí)，顆粒數(shù)量隨超聲功率增加而急劇減少。高能超聲作用下Al3Ti/6070復(fù)合材料的最佳制備工藝為：超聲強(qiáng)度0.66~0.82 kW/cm2，超聲作用時(shí)間3 min。
關(guān)鍵字: 鋁基復(fù)合材料；Al3Ti增強(qiáng)顆粒；高能超聲
（School of Materials Science and Engineering, Jiangsu University, Zhenjiang 210213, China）
Abstract:In-situ Al3Ti/6070 composites were synthesized by direct melt reaction method under high intensity ultrasonic field in Al-K2TiF6 system. The effects of high intensity ultrasonic on the reinforced particles in Al3Ti/6070 composites with different parameters such as ultrasonic radiation time and ultrasonic intensity were investigated by XRD, SEM and EDS. The model of particle motion was established under the high intensity ultrasonic and the mechanism was discussed. The results show that the sizes of the reinforced particles decrease along with ultrasonic radiation time and then increase under a certain ultrasonic intensity (0.66 kW/cm2). When the ultrasonic radiation time is 3 min, the smallest size is obtained. The sizes are in range of 1−2 μm. The morphology of reinforced particles is small blocky or short rod-like. The amount of reinforced particles is decreased sharply with the increase of ultrasonic radiation time when the ultrasonic radiation time is longer than 3 min. Furthermore, the sizes of reinforced particle are decreased along with the increase of ultrasonic intensity when the ultrasonic radiation time is fixed at 3 min. When the ultrasonic intensity is up to 0.82 kW/cm2, the main morphology of reinforced particles is small blocky or granular, and the sizes of the particles are in range of 0.5−1 μm. But the amount of particles is decreased sharply when the ultrasonic intensity is more than 0.82 kW/cm2. The most suitable parameters for fabricating Al3Ti/6070 composites under the high intensity ultrasonic field are: the ultrasonic intensity is in range of 0.66−0.82 kW/cm2 and ultrasonic radiation period is 3 min.
Key words: aluminum matrix composites; Al3Ti reinforced particle; high intensity ultrasonic
