(1.國(guó)防科技大學(xué) 材料工程與應(yīng)用化學(xué)系，長(zhǎng)沙 410073;
2. 航天材料及工藝研究所，北京 100086)
摘 要: 研究了由熱等靜壓工藝制備的B/Al復(fù)合材料在300℃和500℃條件下經(jīng)不同時(shí) 間熱暴露處理后的力學(xué)性能及斷口特征，從界面微觀特征的角度分析了溫度和時(shí)間等參數(shù)對(duì)性能產(chǎn)生影響的原因。實(shí)驗(yàn)結(jié)果表明：在300℃長(zhǎng)時(shí)間(50～100h)熱暴露后，性能下降幅度約為20%～30%；溫度為500℃時(shí)，經(jīng)較短的時(shí)間(數(shù)小時(shí))熱暴露后性能顯著下降。微觀分 析表明：在300℃長(zhǎng)時(shí)間熱暴露后沒(méi)有明顯的界面反應(yīng)，在500℃數(shù)小時(shí)熱暴露后出現(xiàn)纖維和基體的界面反應(yīng)層，界面反應(yīng)的發(fā)生使力學(xué)性能降低。
關(guān)鍵字: B/Al復(fù)合材料；熱暴露；力學(xué)性能；斷口；界面反應(yīng)
mechanical properties of
B/Al composite
（1.Department of Materials Engineering and
Applied Chemistry，National University of
Defence Technology，Changsha 410073，China；
2.Aerospace Research Institute of Materials and
Processing Technology，Beijing 100086, China）
Abstract:The effects of thermal exposure on the mechanic al properties of boron fiber reinforced aluminum composite were studied in terms of tensile strength and fracture elongation. The interfacial microstructure was also analyzed by TEM. The results show that there is no severe decrease of mechanical properties after thermal exposure at 300℃ and no interfacial reaction revealed from the TEM micrograph. Thermally exposed at 500℃, the composite begins to lose their strength dramatically after several hours. The TEM study shows that an obvious interfacial reaction layer appears at this time. The fracture patterns an d fractographies of composite under different thermal exposure conditions show t hat as the properties decrease, the fracture routes become less zigzag and the pull-out of boron fiber gradually reduces.
Key words: B/Al composite；thermal expousure; mechanical properties；fractography；interfacial reaction
