Dispersion - strengthened nanocrystalline copper

• Autorzy: Stobrawa J. P. , Rdzawski Z. M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of this work was to investigate microstructure, mechanical properties and deformation behaviour of dispersion strengthened nanocrystalline copper produced by powder metallurgy techniques. Design/methodology/approach: Tests were performed with the Cu, Cu-tungsten carbide and Cu-yttria micro-composites containing up to 3 wt.% of a strengthening particles. The mechanical properties, initial nanocrystalline structures and their evolution during deformation processes were investigated. Findings: The obtained strengthening effect have been discussed based on the existing theories related to strengthening of nanocrystalline materials. The studies-have shown the importance of "flows" existing in the consolidated materials and sintered materials such as pores or regions of poor powder particle joining which significantly deteriorate mechanical properties of micro-composites produced by powder metallurgy. Research limitations/implications: The powder metallurgy techniques make it possible to obtain copper-based bulk materials by means of milling input powders in the planetary ball, followed by compacting and sintering. Additional operations of hot extrusion are also often used. There is some threat, however, that during high-temperature processing or using these materials at elevated or high temperatures this nanometric structure may become unstable. Practical implications: A growing trend to use new copper-based functional materials is observed recently world-wide. Within this group of materials particular attention is drawn to those with nanometric grain size of a copper matrix, which exhibit higher mechanical properties than microcrystalline copper. Originality/value: The paper contributes to the mechanical properties of dispersion strengthened (with tungsten carbide and yttria) nanocrystalline copper and to the elucidation of deformation behaviour of these materials with high porosity.

Słowa kluczowe

EN

nanomaterials; mechanical properties; electron microscopy; metallography; powder metallurgy

PL

nanomateriały; właściwości mechaniczne; mikroskopia elektronowa; metalografia; metalurgia proszków

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 24, nr 2
• Strony: 35--42
• Opis fizyczny: Bibliogr. 15 poz., fot., rys., tab.

Twórcy

autor

Stobrawa J. P.

autor

Rdzawski Z. M.

• Division of Materials Processing Technology, Management and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18 a, 44-100 Gliwice, Poland,

Bibliografia

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