Nanostructured materials mechanical properties

P. Motamedi, R. Bagheri, Investigation of the nanostructure and mechanical properties of polypropylene/polyamide 6/layered silicate ternary nanocomposites. Materials and Design 31 (4) (2010) 1776-1784. 

The fabrication of implants with controlled nanostructures has very important advantages from the point of view of clinical applications. An appropriate design at the nanostructural level results in better implant-body interactions, improved mechanical properties, and control of the material biodegradation. 

Bioactive materials can be used as powders for filling small defects and as coatings that enhance metallic prosthesis fixation. However, when considering bioactive materials for bone regeneration in medium and large defects, bioactive pieces with appropriate mechanical properties are required. At this point, the key is to keep the properties provided by the nanostructure when processing a piece at the macroscopic... 

It is necessary to disperse the nanomaterials in the best possible manner, especially those layered structures such as graphite, graphene or clays. It is important to obtain very thin (ca. one nanometer) and very wide (ca. 500 nanometers) nanostructures dispersed in the polymer matrices to achieve optimal gas permeability and to improve their mechanical properties without affecting structural quality, using a small amount of the nanomaterial. The particle orientation also has an important effect on the properties of the nanocomposite. Nanoparticles need to be dispersed within the polymer so that are parallel to the material s surface. This condition ensures a maximum tor-... 

Accurate control of microstructure on nanometric scale makes it possible to control magnetic and mechanical properties to a hitherto unattainable degree. In particular, magnetic nanostructures have recently become the subject of an increasing number of experimental and theoretical studies. The materials are made of alternating layers, around 10 A thick, of magnetic (e.g., cobalt) and nonmagnetic metals (e.g., copper). 

The development of composite structural materials based on ordered nanostructures in a matrix material has been surprisingly difficult to accomplish, and has only proved successful in a few cases165. Part of the difficulty is that the surface chemistry of the nanostructures must be controlled carefully so that the structure truly is a composite and that the nanostructured phase in the matrix is ordered. Given the importance of nano-scale heterogeneity in determining the mechanical properties of materials, this area is one of great theoretical and practical interest. 

Siegel, R. W., and Fougere, G. E., Mechanical properties of nanophase metals. Nanostructured Materials 6,205 (1995a). 

Abstract The focus of this chapter is primarily directed towards nanocrystalline soft magnetic materials prepared by crystallization of amorphous precursors. The key elements involved in the development of this class of materials are three-fold (i) theoretical models for magnetic softness in nanostructures (ii) nanostructure-property relationships and (iii) nanostructural formation mechanisms. This chapter surveys recent research on these three areas with emphasis placed on the principles underlying alloy design in soft magnetic nanostructures. 

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