力學(xué)性能
(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083；
2. 中南大學(xué) 機(jī)電工程學(xué)院， 長沙 410083)
摘 要: 用噴射沉積法制備快凝Al-8.5Fe-1.3V-1.7Si合金沉積坯， 通過金相、 X射線衍射、 透射電鏡、 掃描電鏡、 拉伸力學(xué)性能測試等分析手段研究快凝Al-Fe-V-Si合金噴射沉積坯的顯微組織與力學(xué)性能。 結(jié)果表明， 噴射沉積Al-Fe-V-Si合金坯是由形狀大小不同的霧化液滴沉積凝固微區(qū)(粉末)構(gòu)成， 也存在大量的孔隙和原始粉末界面。 沉積坯主要由α(Al)+Al12(Fe, V)3Si(bcc，a≈1.260 nm)的兩相混合組織構(gòu)成， 細(xì)小的Al12(Fe, V)3Si球形顆粒均勻分布在α(Al)基體上， 但不同粉末內(nèi)部組織形態(tài)存在差異， 使沉積坯表現(xiàn)出組織微觀不均勻性。 噴射沉積坯的力學(xué)性能與坯體致密度存在強(qiáng)烈的依賴關(guān)系， 大量孔隙和原始粉末界面的存在使得坯體強(qiáng)度和塑性都處于較低的水平。
關(guān)鍵字: Al-Fe-V-Si合金; 耐熱鋁合金; 噴射沉積; 快速凝固
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China）
Abstract: Spray deposition was applied to produce deposited billets of rapidly solidified Al-8.7Fe-1.3V-1.8Si aluminum alloy in the atomization medium of nitrogen gas. Microstructural features and mechanical properties of the spray deposited billets were studied by means of optical microscopy (OM), X-ray diffraction (XRD), transmission electron microscopy (TEM) with energy dispersive X-ray (EDX) spectrometer and measurement of tensile properties. The results show that, the spray deposited billets of Al-Fe-V-Si alloy consist of platelets (powder particles) with various size and shape, deposited and solidified from the atomized liquid droplets, and a large amount of irregular porosity (or pinhole) and prior particle boundaries also exist in the as-solidified deposit. The spray deposited billets consist of two phases mixture of α(Al) and Al12(Fe, V)3Si (bcc, a≈1.260 nm), which is characterized generally as the fine Al12(Fe, V)3Si particles dispersed uniformly in the α(Al) matrix. However, the various powder particles have different microstructural morphologies and thus the spray deposited billets exhibit structural inhomogeneity on the micro scale. The mechanical properties of the spray deposited materials are mightily dependent on relative compacted density of the billets, and the large amount of irregular porosity (or pinhole) and prior particle boundaries result in that the tensile strength and elongation of the billets are at the low level.
Key words: Al-Fe-V-Si alloy; heat-resistant aluminum alloy; spray deposition; rapid solidification
