1 250℃烧结Fe-28Al-5Cr(at.%)合金结构的透射电子显微学表征
张可翔1，2，3，贺连龙1，2*
（1.中国科学院金属研究所，沈阳材料科学国家（联合）实验室，辽宁 沈阳 110016；2.中南大学，轻质高强结构材料国家重点实验室，湖南 长沙410012；3. 中国科学院大学，北京100049）
摘 要 利用透射电子显微镜（TEM）研究了一种在1250℃下热压烧结的Fe-28Al-5Cr (at.%)合金的显微结构。研究结果表明：基体由DO3型有序相Fe3Al组成，Cr以固溶方式存在于基体中。α-Al2O3主要沿Fe3Al晶界析出，晶内也有少量分布。这些α-Al2O3析出相颗粒表面通常会形成尖晶石结构的FeAl2O4包裹层。同时发现基体三叉晶界处有孔洞的形成，且孔洞中松散填充着α-Al2O3颗粒。在Fe3Al晶内存在着a/2<110>刃型全位错。
关键词 Fe-Al-Cr合金；晶界析出；氧化；位错
中图分类号：TG142.41；O77+2；TG115.21+5.3 文献标识码：A doi:10.3969/j.issn.1000-6281.2016.04.005
TEM characterization of the microstructures of Fe-28Al-5Cr (at.%) alloy sintered at 1 250℃
ZHANG Ke-xiang1，2，3，HE Lian-long1，2*
(1.Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang Liaoning 110016；2.National Key Laboratory of Science and Technology on High-strength Lightweight Structural Materials, Central South University，Changsha Hunan 410012；3. University of Chinese Academy of Sciences，Beijing 100049，China)
Abstract The microstructures of a Fe-28Al-5Cr (at.%) alloy sintered at 1250℃ was studied by transmission electron microscopy (TEM). The result shows that the main phase is DO3 type Fe3Al phase and the element Cr acts as solute atom in the Fe3Al grains. There are some α-Al2O3 precipitations and most of them exist at the Fe3Al grain boundaries. It is interesting that these α-Al2O3 are capsulated by a FeAl2O4 layer, which is a typical spinel structure. Besides, some micropores were formed at the triple junction of grains, and these micropores were filled with α-Al2O3 particles incompactly. The typical a/2<110> edge dislocations existed in the matrix Fe3Al grains.
Keywords Fe-Al-Cr alloy；grain boundary precipitation；oxidation；dislocations
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[1] DEEVI S C, SIKKA V K, LIU C T. Processing, properties, and applications of nickel and iron aluminides[J]. Progress in Materials Science，1997，42:177-192.
[2] WANG H D, LA P Q，LIU X M, et al. Effect of chromium content on microstructure and mechanical properties of large dimensional bulk nanocrystalline based Fe-Al-Cr alloys prepared by aluminothermic reaction [J]. Materials and Design，2013，47:125-132.
[3] LOU B Y, LIU M S, CHANG X B, et al. Influence of Mn addition on the ordering of DO3 Fe-28%Al intermetallics [J]. Journal of Materials Science，1999，34:4039-4042.
[4] 刘勇，朱景川，王慧，等. Fe-24Al-1Cr合金固溶时效处理的组织和力学性能[J]. 金属热处理，2013，38(1):84-87.
[5] NOWACKI J, RYLSKA D. Fe-Al-Cr heat resistant sinters [J]. Journal of Materials Processing Technology，2001，109:138-141.
[6] MONTEALEGRE M A, STREHL G, GONZALEZ-CARRASCO J L, et al. Oxidation behaviour of novel ODS FeAlCr intermetallic alloys [J]. Intermetallics，2005，13:896-906.
[7] ZHANG Z G, HOU P Y, GESMUNDO F, et al. Effect of surface roughness on the development of protectiveAl2O3 on Fe–10Al (at.%) alloys containing 0–10 at.% Cr[J]. Applied Surface Science，2006，253:881–888.
[8] AUINGER M, PRAIG V G, LINDER B, et al. Grain boundary oxidation in iron-based alloys, investigated by 18O enriched water vapour – The effect of mixed oxides in binary and ternary Fe–{Al, Cr, Mn, Si} systems [J]. Corrosion Science，2015，96:133-143.
[9] 左孝青，周芸，梅俊，等. 挤压-烧结法制备铁铬铝金属蜂窝的组织与性能[J]. 机械工程材料，2006，30(10):34-37.
[10] DEEVI S C, SIKKA V K. Nickel and iron aluminides: an overview on properties, processing, and applications [J]. Intermetallics，1996，4:357-375.
[11] BAI Y P, XING J D, WU H L, et al. Study on preparation and mechanical properties of Fe3Al-20 wt.%Al2O3 composites [J]. Materials and Design，2012，39:211-219.
[12] 曾小龙，周浩宇. 对Fe-Al-Cr耐热烧结矿的结构分析[J]. 金属材料与冶金工程，2007，35(2):40-43.
[13] MORRIS D G, MUNOZ-MORRIS M A. Creep behaviour of iron-aluminium-chromium intermetallics strengthened by nano-sized oxide particles [J]. Materials Science&Engineering A，2014，607:376–382.
[14] MORRIS D G, MUNOZ-MORRIS M A. Nanoprecipitation of oxide particles and related high strength in oxide-dispersion-strengthened iron–aluminium–chromium intermetallics [J]. Acta Materialia，2013，61:4636–4647.
