反应物量对纳米晶Fe_3Al组织和性能的影响

Effect of Reactants Quantity on Nanostructure and Mechanical Properties of Bulk Nanocrystalline Fe_3Al

利用铝热反应熔化方法分别在反应物量为50、100、200g的条件下制备了块体纳米晶Fe3Al材料,通过TEM和XRD研究了材料的晶粒尺寸,并研究了材料室温压缩性能和硬度。结果表明,所制备的材料主要由非晶和纳米晶组织组成,当反应物量增大,部分区域甚至出现微米晶组织。反应物量为50g时Fe3Al材料中非晶较多,不存在微米晶;反应物量为100g时主要以纳米晶为主,非晶数量减少,伴随有少量的微米晶出现;反应物量为200g时,材料以纳米晶为主,微米晶数量较100g时有所增加。随着反应物量的增加,纳米晶相的平均晶粒尺寸增加,屈服强度和硬度呈先增大后减小的趋势。

Bulk nanocrystalline Fe3Al materials were prepared by aluminothermic reaction in different quantities of the reactant ranged from 50 to 200 g. The grain size was studied by means of TEM and XRD, and the compressive strength and hardness of the materials were tested at room temperature. The results show that the materials consist of amorphous and nanocrystalline phases and a few of micron grains appear in some regions of the materials with increase of the reactant quantities. When the reactant quantity is 50 g, the material has more amorphous phases and no micron grains phases. When it is 100 g, the material consists of more nanocrystalline phases and few of micron grains phases. When it is 200 g, the material mainly has nanocrystalline phases and micron grains phases, and the amount of micron grains phases is more than that of materials prepared in 100 g reactant. The average grain size of the materials increased, the yield strength and hardness of the materials first increased and then decreased with increase of the reactant quantities.