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Determination of mechanical properties of nanocrystalline
materials by means of acoustic microscopy : application of
pure elements (Fe and Ti) and alloys (Fe-Cu)
Hong Son Cao(1)
, Jean Jacques Hunsinger (2)
, Régis Bonnet
(3)
and Omar Elkedim(1)
通过声波显微镜研究纯金属铁粉和钛粉以及铁-铜合金的纳米晶体机械性能
众所周知机械研磨的方法是制备纳米晶体粉末合合金的通用方法。材料的机械特性通
过高频声波显微镜研究。对于合金来说，事实证明经典的声波公式可用于计算铁-铜纳米晶
体的弹性恒量。
1. Introduction
Nanostructured materials are distinguished from conventional polycrystalline materials by their extremely fine
crystallite sizes. Because of the extremely small dimension of the grains, a large fraction of the atoms in these
materials is located in the grain boundaries. This confers special attributes to this class of new materials.
The elastic modulus of a material is related to the atomic binding forces and characterizes the elastic properties
of the material under loading. Young modulus can be measured by sound velocity (Korn et al 1988, Kobelev et al,
1993, Sanders et al 1999), tensile testing (Korn et al 1988, Nieman et al 1991, Wong et al, 1994, Sakai et al 1999 ),
nanoindentation (Mayo et al 1992, Mayo et al 1990, Fougere et al 1995) in nc-metals and nc-ceramics upon
compacted powders.
Compared to conventional metal, the ratio E/E0 (where E and E0 represent Young’s modulus of nc-metal and
conventional metal respectively) is very variable, usually weak, due to important residual porosity which is often
not measured.
The objective of the present study is to determine mechanical properties and especially elastic modulus for
nc-metals (Fe and Ti) and nc-alloys (Fe-Cu). Dense nanomaterials are necessary involving consolidation of small
samples with high pressure.
2. Experimental procedure
本工作中的金属纳米晶体和合金纳米晶体都通过球磨制备。使用德国莱驰行星式
高能球磨仪，400转/分钟，研磨时间24小时，研磨时间足够长确保能够得到纳米晶体。
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