在诸如AAS、NIR、ICP以及XRF等等的化学和物理分析方法中，分析样品不仅必须要预先经粉碎达到一定的满足分析要求细度，同时还必须达到尽可能高的均化度。 可靠而且准确的样品分析必须有可重复性的样品前处理进行保障。RETSCH在这一领域为您提供一整套完整的解决 方案，包括各种最现代化的研磨仪和粉碎仪，能够提供满足各种样品特性要求的粗粉碎、细粉碎和超细度粉碎处理。丰富的研磨件（切割头）和配件供应保证了我们 的仪器能够在各种前提下实现满足分析要求的样品前处理，消除粉碎过程中产生样品污染的可能性，同时满足对样品本身进行温和维护的要求。
Determination of mechanical properties of nanocrystalline materials by means of acoustic microscopy : application of pure elements (Fe and Ti) and alloys (Fe-Cu)
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.
