(中南大學(xué) 材料科學(xué)與工程學(xué)院, 長沙 410083)
摘 要: 利用快速凝固粉末冶金方法制備了TiB2顆粒增強Al-8.5Fe-1.3V-1.7Si耐熱鋁合金試樣以及不含TiB2顆粒的基體合金試樣, 通過光學(xué)顯微鏡、掃描電鏡分析了其顯微組織和斷口形貌, 采用X射線衍射進行了物相分析, 并進行力學(xué)性能測試。結(jié)果發(fā)現(xiàn)，TiB2顆粒能有效地添加到Al-8.5Fe-1.3V-1.7Si耐熱鋁合金基體中, 并能有效地抑制平衡相Al13Fe4的析出, 且能細(xì)化晶粒, TiB2顆粒的存在使得粒度小于74 μm粉末冶金合金擠壓試樣的室溫強度高達(dá)454 1 MPa, 屈服強度達(dá)407 8 MPa, 延伸率保持在7.7％; 350 ℃高溫強度穩(wěn)定在210 MPa以上, 延伸率穩(wěn)定在7.7%以上。
關(guān)鍵字: TiB2; 耐熱鋁合金; 快速凝固; 粉末冶金
HUANG Bai-yun
（ School of Materials Science and Engineering,
Central South University, Changsha 410083, China）
Abstract: The samples of Al-8.5Fe-1.3V-1.7Si aluminium alloy with and without TiB2 particles reinforcement were prepared by rapid-solidified powder metallurgy. The microstructure and fractography of the samples were studied by means of the optical microscope and scanning electron microscope, and the mechanical properties were analyzed by tensile experiment. The results show that TiB2 particles can be added to the AlFeVSi aluminium alloy and restrains the form of equilibrium phase Al13Fe4 . The crystal grain is refined and the mechanical properties are improved. The samples with TiB2 particles which are smaller than 74 μm show the best mechanical properties.The fracture strength, yield strength and elongation reach to 454 1 MPa, 407 8 MPa, 7.7％ respectively at room temperature. The elevated temperature strength and elongation stay stable over 210 MPa and 7.7% at 350 ℃.
Key words: TiB2; heat-resistant aluminium; rapid-solidified; powder metallurgy
