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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.

2

The structure and corrosive properties of the CoCr-base dental alloy obtained by soft material milling followed by sinterization

Rylska D., Sokołowski G., Konieczny B., Sokołowski J.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 74, nr 2

60--71

EN

Purpose: Presented researches aimed at evaluating the structure and corrosion properties of CoCr-base elements fabricated by means of soft material milling with later sinterization in a protective atmosphere in comparison to casted alloy. Design/methodology/approach: CoCr-base samples were fabricated by soft material milling followed by sinterization in neutral gas environment and casted by traditional casting techniques. EDS-SEM study was used to evaluate the microstructure and quantitative analysis of chemical composition. Corrosion resistance evaluation was based on examining corrosion parameters (Ecorr, jcorr, Rpol), corrosion behaviour of both kind of samples was also studied by using open circuit potential v/s time measurements to assess the protective nature of the applied manufacturing methods and by potentiodynamic polarisation technique. Findings: Differences in structure were found, sintered material was more homogenous in comparison to dendritic structure of the cast alloy. Corrosion parameters (corrosion potential - Ecorr, corrosion current density - jcorr, polarization resistance Rp , open circuit potential versus time - OCP) indicate higher corrosion resistance of sintered element. Course of the polarization curve proves, that the sintered alloy exhibits better self-passivating properties in comparison to casted material. Research limitations/implications: The research was carried out on samples, not on final restoration elements. As the technology based on soft CoCr-base alloy milling followed by sinterization in neutral gas environment has been developed last years, additional investigations are needed to obtain more precise results in corrosion properties evaluation. Originality/value: PM technology based on soft material milling with later sintering in a protective atmosphere is the new technology used for fabrication of metal prosthodontic dentures. This method seems to be promissing alternative to laser micro-sintering, and makes it possible to achieve a product with a far more homogenous structure in comparison to traditional casting and does not require as expensive instrumentation necessary for the SLM method. It is crucial to examine in details the corrosion resistance of elements obtained by this new technology.

3

Odporność na korozję elektrochemiczną drutów przeznaczonych na prowadniki kardiologiczne

Przondziono J., Walke W., Dańczak G.

Hutnik, Wiadomości Hutnicze

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2011

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Vol. 78, nr 1

104-106

PL

W pracy przedstawiono wyniki badań odporności na korozję elektrochemiczną drutów wykonanych ze stali nierdzewnej X10CrNi18-8 przeznaczonych na prowadniki stosowane w kardiologii inwazyjnej. Pomiary realizowano w roztworze sztucznego osocza z wykorzystaniem systemu do badań elektrochemicznych VoltaLabŽPGP201. Na podstawie zarejestrowanych krzywych polaryzacji wyznaczono charakterystyczne wielkości opisujące odporność na korozję elektrochemiczną, tj.: potencjał przebicia, opór polaryzacyjny, gęstość prądu korozyjnego, a także szybkość korozji. Określono wpływ odkształcenia w procesie ciągnienia oraz sposobu przygotowania powierzchni drutów na ich odporność na korozję elektrochemiczną.

EN

The work presents the results of electrochemical corrosion tests of wire made of stainless steel X10CrNi18-8. The tests were performer in artificial plasma solution with the use of electrochemical testing system VoltaLabŽPGP201. On the ground of recorded polarization curves, typical characteristics that describe electrochemical corrosion have been determined, i.e.: breakdown potential, polarization resistance, corrosive current density and corrosion rate. The impact of strain in the drawing process and ways of wire surface preparation to their electrochemical corrosion have been determined.

4

Elektrochemiczna odporność korozyjna stopów NiTi

Łosiewicz B., Lekston Z., Freitag M., Wierzchoń T., Lelątko J.

Engineering of Biomaterials

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2011

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Vol. 14, no. 109-111 spec. iss.

15--17