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Accumulative roll bonding fabrication, tensile and corrosion characterization of Zn/Al multilayered composites

Mosafajahanabad Nasim, Alizadeh Morteza, Salahinejad Erfan

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e191, 2022

EN

In the present work, accumulative roll bonding (ARB) processing and characteristics of Zn/6 wt% Al multilayered composite sheets were investigated for the first time. The structure of the fabricated composites was evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Tensile testing and fractography were used to assess the strength and elongation of the composites. The corrosion behavior of the fabricated samples was also investigated by potentiodynamic polarization and electrochemical impedance spectroscopic tests in the 3.5 wt% NaCl solution. Despite the evolution of atomic intermixing at the interface of the layers and grain refinement, the tensile strength and elongation of the composites were reduced by increasing ARB cycles due to the domination of plastic instability introduced by the ARB process. In addition, an initial increase until the third ARB cycle followed by decrease in the corrosion tendency of the composites was found by progression of the ARB process, which was attributed to a compromise between the levels of structural defects and homogeneity. It is eventually concluded that after optimizing the mechanical and corrosion behaviors as a function of the number of ARB cycles, ARB-processed Zn/Al multilayered composites can be further considered in industrial applications.

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The examples of the research of the nanostructured engineering materials and the concept of the new generation of highly innovative advanced pioneering nanostructured composite materials

Dobrzański L. A.

Archives of Materials Science and Engineering

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2016

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Vol. 82, nr 1

5--37

EN

Purpose: The first part of the paper presents the outcomes of a dozen of own researches in the field of nanotechnology, carried out over the last several years. The second part of the paper presents the new Author’s ideas on the predicted development of the new generation of highly innovative advanced pioneering nanostructured composite materials through the interaction of the extended nanoengineering components. Design/methodology/approach: Each of the selected topics was briefly described, with special emphasis laid on the issue of structural and phase transitions, which are generally taking place in the newly created original engineering materials and their related original technologies. Each of the descriptions was arbitrarily illustrated with a metallographic photographs made with electron microscopes, most often a transmission microscope, mainly a high-resolution or scanning microscope. The scientific objective of the planned research is to recognise and explain the relevant structural mechanisms, in each case, of synthesis and/or production and formulation of the structure and properties of a new generation of pioneering nanostructured composite materials through the interaction of the extended nanoengineering components and to characterise and model their structure and properties depending on the compositional, phase and chemical composition and the applied synthesis and/or production and/or processing processes. Findings: The research covered by the paper is pursued in the field of nanotechnology as the designing and manufacture of structures with new properties resulting from a nanosize. The planned research is of priority cognitive importance as theoretical considerations, indicate a great need to intensify scientific research to develop new groups of materials with completely unexpected foreseeable effects, resulting from the use of the extended nanoengineering components for manufacturing super advanced nanocomposite materials. Phenomena and processes at a nanoscale can be better recognised by producing a new generation of functional nanostructural materials. Practical implications: The measurable scientific effects concern the cognitive nature of the planned research and are associated with the determination of: the effect of compositional, phase and chemical composition, of the newly developed technologies of fabrication and surface micro-treatment inside pores, of internal precipitated phases or nanoinclusions or surface treatment of micropores in order to apply nanomaterials enabling the improvement of specific properties on the structure and properties of the newly created nanocomposite materials with the extended nanoengineering components ensuring the improvement of specific properties and the modelling of the structure and properties of the researched newly created nanocomposite materials using artificial intelligence methods. The research will comprise the fabrication of materials with new unforeseeable properties fulfilling multiple functions. Originality/value: Phenomena and processes at a nanoscale can be better recognised by producing a new generation of functional nanostructural materials (physicochemical basis of nanomaterials and nanostructures synthesis, with controlled architecture and properties, engineering of atomic and molecular bonds, models and theories explaining the properties of nanomaterials, surface phenomena, self-assembly phenomena in nanomaterials and nanostructures synthesis, magnetic phenomena in semiconducting and metallic nanostructures).

3

Mechanical alloying of Mg-based metallic glasses and nanostructured composites.

Eckert J.

Archives of Materials Science

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2004

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Vol. 25, nr 4

321-331

EN

Mg55Y15Cu33-based metallic glass matrix composites are produced by mechanical alloying of elementar powder mixtures containing up to 3- vol. % of Y2O3 particles. Comparison with the particle-free metallic glass reveals that the nanosized second phase oxide particles do not significantly affect the glass-forming ability upon mechanical alloying despite some limited particle dissolution. A supercooled liquid region with an extension of about 50 K can be maintained in the processes of the oxides. The distinct viscosity decrease in the supercooled liquid regime allows for consolidation of powders into bulk samples by uniaxial hot pressing. The Y2O3 additions increase the mechanical strength of the composites compared to the Mg55Y15Cu33 metallic glass.