底材厚度对铝热反应熔化制备的块体纳米晶Fe3Al材料的组织和性能的影响

通过铝热反应熔化方法在厚度为5~15 mm的铜底材上制备块体纳米晶Fe3Al材料.通过X射线衍射(XRD)研究材料的晶粒尺寸,研究材料室温压缩下的力学性能和硬度.结果表明,所制备材料的晶粒尺寸均约为20nm,且晶粒尺寸随底材厚度的增加而增加.底材厚度为5 mm时纳米晶Fe3Al材料的屈服强度和硬度具有最大值,随着底材厚度的增加,屈服强度和硬度急剧减小,最后趋于稳定.5 mm时纳米晶Fe3Al材料的屈服强度约是10mm时的1.5倍.

Effect of substrate's thickness on microstructure and mechanical properties of bulk nanocrystalline Fe3Al prepared by aluminothermic reaction

Bulk nanocrystalline Fe3Al materials were prepared by aluminothermic reaction on the substrates with different thickness in 5~15 mm.The sizes of crystalline grains of the prepared material were measured with X-ray diffraction(XRD).Compressive strength and hardness of the material were tested.The results showed that grain size of the materials were nearly 20 nm and the grain size increased with the substrate's thickness.Yield strength and hardness reached their maximum values when the thickness of substrate was 5 mm and they remarkably decreased and lastly became uniform with the thickness of substrate.Yield strength of the material with the thickness of substrate being 5 mm was nearly 1.5 times of that when the thickness of substrate was 15 mm.