6066Al/SiC_p复合材料的组织特征与阻尼性能

来源期刊：中南大学学报(自然科学版)2001年第5期

论文作者：罗兵辉 柏振海 谢佑卿

文章页码：511 - 514

关键词：复合材料;铝合金;碳化硅;阻尼能力

Key words：composites; Al alloy; silicon carbide; damping capacity

摘    要：研究了经制粉→混料→真空抽气→热挤压工艺制备的6066Al/SiC_p复合材料的组织特征与阻尼性能.复合材料的阻尼特征通过动态机械热分析仪(DMTA)测量,得出了2种不同SiC含量的6066Al/SiC_p复合材料及6066Al合金在温度为30~250℃,频率为0.1,1,10和30 Hz时的阻尼值.利用扫描电镜、光学显微镜对复合材料组织特征进行了分析,根据组织特征及阻尼数据对复合材料的阻尼机制进行了讨论.结果表明:将2~3μm的SiC颗粒加入6066Al中,当SiC含量为7%(体积分数)时,增强的SiC颗粒分布较均匀,与基体结合良好;当SiC含量为12%时,SiC易聚集成团.少量SiC能明显提高6066Al的阻尼能力,尤其是高温阻尼性能;6066Al/SiC_p复合材料的高阻尼性能主要是SiC颗粒加入后使位错密度大大增加,基体晶界及基体与SiC颗粒界面的存在使材料在循环载荷下消耗能量所致.

Abstract: Microstructure characteristic and damping properties of the 6066Al/SiC_p composites produced by spray powder →blending→canning+degassing→hot pressing process were studied. The damping capacity 6066Al base alloy and the 6066Al/SiC_p composites, with two different volume fractions of reinforcements, were measured at frequencies of 0.1, 1,10 and 30 Hz over in the 30 to 250℃temperature range by a dynamic mechanical thermal analyzer (DMTA). The mi- crostructural analysis was performed using scanning electron microscopy, optical microscopy. Itwas shown that 2~3μm SiC particulates gathered easilywhen the volume fraction of SiC reinforcing particulates present in the MMCs was up to 12%. The damping capacity of 6066Al could be significantly improved by the addition of 7% SiC particulates. Finally,the operative damping mechanisms were discussed in light of characterization of microstructure and the data of damping capacity.