National Technical Reports Library

The National Technical Information Service acquires, indexes, abstracts, and archives the largest collection of U.S. government-sponsored technical reports in existence. The NTRL offers online, free and open access to these authenticated government technical reports. Technical reports and documents in its repository may be available online for free either from the issuing federal agency, the U.S. Government Publishing Office’s Federal Digital System website, or through search engines.

Details

Properties and nanostructures of nano-materials processed by severe plastic deformation (spd).

DE2001776690

Publication Date	2001
Personal Author	Zhu, Y. T.
Page Count	13
Abstract	Metallic materials usually exhibit higher strength but lower ductility after being plastically deformed by conventional techniques such as rolling, drawing and extrusion. In contrast, nanostructured metals and alloys processed by severe plastic deformation (SPD) have demonstrated both high strength and high ductility. This extraordinary mechanical behavior is attributed to the unique nanostructures generated by SPD processing. The combination of ultrafine grain size and high-density dislocations appears to enable deformation by new mechanisms not active in coarse-grained metals and alloys. These results demonstrate the possibility of tailoring the microstructures of metals and alloys by SPD to obtain superior mechanical properties. Nanostructured metals and alloys processed by SPD techniques have unique nanostructures not observed in nano-materials synthesized by other techniques such as the consolidation of nanopowders. The SPD-generated nanostructures have many features related to deformation, including high dislocation densities, and high- and low-angle grain boundaries in equilibrium or non-equilibrium states. Future studies are needed to investigate the deformation mechanisms that relate the unique nanostructures with the superior mechanical properties exhibited by SPD-processed metals and alloys.
Keywords	Alloys Ductility Mechanical properties Deformation Dislocations Extrusion Grain boundaries Grain size Plastics Rolling
Source Agency	Technical Information Center Oak Ridge Tennessee
NTIS Subject Category	71N - Nonferrous Metals & Alloys
Corporate Authors	Los Alamos National Lab., NM.; Department of Energy, Washington, DC.
Document Type	Conference Proceedings
NTIS Issue Number	200125
Contract Number	W-7405-ENG-36

Properties and nanostructures of nano-materials processed by severe plastic deformation (spd).

Properties and nanostructures of nano-materials processed by severe plastic deformation (spd).
DE2001776690

Publication Date	2001
Personal Author	Zhu, Y. T.
Page Count	13
Abstract	Metallic materials usually exhibit higher strength but lower ductility after being plastically deformed by conventional techniques such as rolling, drawing and extrusion. In contrast, nanostructured metals and alloys processed by severe plastic deformation (SPD) have demonstrated both high strength and high ductility. This extraordinary mechanical behavior is attributed to the unique nanostructures generated by SPD processing. The combination of ultrafine grain size and high-density dislocations appears to enable deformation by new mechanisms not active in coarse-grained metals and alloys. These results demonstrate the possibility of tailoring the microstructures of metals and alloys by SPD to obtain superior mechanical properties. Nanostructured metals and alloys processed by SPD techniques have unique nanostructures not observed in nano-materials synthesized by other techniques such as the consolidation of nanopowders. The SPD-generated nanostructures have many features related to deformation, including high dislocation densities, and high- and low-angle grain boundaries in equilibrium or non-equilibrium states. Future studies are needed to investigate the deformation mechanisms that relate the unique nanostructures with the superior mechanical properties exhibited by SPD-processed metals and alloys.
Keywords	Alloys Ductility Mechanical properties Deformation Dislocations Extrusion Grain boundaries Grain size Plastics Rolling
Source Agency	Technical Information Center Oak Ridge Tennessee
NTIS Subject Category	71N - Nonferrous Metals & Alloys
Corporate Authors	Los Alamos National Lab., NM.; Department of Energy, Washington, DC.
Document Type	Conference Proceedings
NTIS Issue Number	200125
Contract Number	W-7405-ENG-36