(哈爾濱工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院, 哈爾濱 150001)
摘 要: 采用擠壓鑄造法制備了晶須體積分?jǐn)?shù)為20％的硼酸鋁晶須增強(qiáng)6061鋁基([AlBO]w/6061Al)復(fù)合材料， 并采用硬度分析、 DSC示差熱分析及透射電鏡分析的方法對(duì)復(fù)合材料的時(shí)效行為進(jìn)行了研究。 結(jié)果表明， 壓鑄法制備的Al18B4O33/6061Al復(fù)合材料中存在高密度的位錯(cuò)， 同時(shí)復(fù)合材料基體晶粒細(xì)小。 經(jīng)固溶淬火處理后， 隨著時(shí)效時(shí)間的增加， 復(fù)合材料的硬度值先下降而后又有所回升， 并在8 h左右出現(xiàn)一個(gè)峰值硬度， 其硬度明顯高于6061Al合金。 復(fù)合材料固溶處理后硬度值較高是由合金元素的固溶強(qiáng)化所致。 由于Al18B4O33晶須和基體6061Al發(fā)生了嚴(yán)重的界面反應(yīng)， 使Mg元素大量消耗， 導(dǎo)致峰時(shí)效強(qiáng)化效果不如固溶強(qiáng)化效果顯著。
關(guān)鍵字: 復(fù)合材料； 硼酸鋁晶須； 時(shí)效； 鋁合金
[AlBO]w/6061Al composite
（ School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China）
Abstract: 6061Al matrix composite reinforced by 20%(volume fraction) Al18B4O33 whisker ([AlBO]w/6061Al) was fabricated by a squeeze casting technique. Age hardening behavior of the composite was investigated by means of hardness measurement, DSC and TEM. The results indicate that there are high density dislocations in the matrix of the composite and the grain of the matrix is finer compared with that of the 6061Al. It is also found that the hardness of the composite is much higher than that of the 6061Al, and with increasing aging time after solution treatment, hardness of the composite decreases firstly and then increases until a peak hardness reaches at 8 h aging. The highest hardness of the composite in the solution state is due to the solution strengthening. The decreasing peak hardening effect of the composite compared with 6061Al is caused by the decrease in amount of Mg element, which is resulted from the interfacial reaction between Al18B4O33 whisker and 6061Al.
Key words: composites; Al18B4O33 whisker; aging; aluminum alloy
