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Badania korozyjne amorficznego i krystalicznego stopu Mg36,6Cu36,2Ca27,2 w płynie fizjologicznym

Nowosielski R., Cesarz K., Nawrat G., Maciej A., Babilas R.

Ochrona przed Korozją

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2013

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nr 4

144--151

PL

Celem pracy jest zbadanie odporności na korozję elektrochemiczną szkła metalicznego Mg36,6Cu36,2Ca27,2 w stanie bezpośrednio po odlaniu oraz po wygrzewaniu. W ramach pracy przeprowadzono badania struktury analizowanych próbek za pomocą badań rentgenowskich i mikroskopowych. W celu określenia szybkości roztwarzania badanego stopu Mg36,6Cu36,2Ca27,2 oraz jego przydatności do potencjalnych zastosowań biomedycznych przeprowadzono badania immersyjne i potencjodynamiczne odporności na korozję elektrochemiczną w płynie fizjologicznym (wieloelektrolitowym). Stwierdzono, że stop Mg36,6Cu36,2Ca27,2 o strukturze amorficznej charakteryzuje się znacznie wyższą odpornością korozyjną od stopu Mg36,6Cu36,2Ca27,2 o strukturze krystalicznej.

EN

The aim of this paper is to investigate the electrochemical corrosion resistance of metallic glass Mg36,6Cu36,2Ca27,2 in as-cast state and after annealing. In the work was carried out studies of the structure of the analyzed samples using X-ray diffraction and microscopic observation. In order to determine the dissolution rate of the tested alloy Mg36,6Cu36,2Ca27,2 and potential suitability for biomedical applications were carried out immersion test and potentiodynamic test electrochemical corrosion in a physiological fluid (electrolyte solution). It was found that Mg36,6Cu36,2Ca27,2 alloy with amorphous structure has a much higher corrosion resistance than the same alloy with crystalline structure.

2

Structure and corrosion properties of Mg70-xZn30Cax(x=0.4) alloys for biomedical applications

Nowosielski R., Cesarz K., Babilas R.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 58, nr 1

7--15

EN

Purpose: The main objective of the paper was to investigate the structure and corrosion properties of amorphous and crystalline Mg-based alloys for biodegradable implants. This paper presents a preparation method and the structure, microhardness and corrosion properties characterization of Mg70Zn30and Mg66Zn30Ca4 alloys in the form of plates. Design/methodology/approach: The studied samples were prepared by the pressure die-casting to copper mould. The structure of the both alloys was examined by X-ray diffractometry (XRD) and a scanning electron microscope (SEM). The thermal properties of the samples were examined using a differential scanning calorimeter (DSC). In addition, corrosion properties research (immersion tests) were performed in a physiological fluid. Microhardness was measured using the Vickers microtester. Findings: The results of X-ray diffraction investigations confirmed that the sample of Mg66Zn30Ca4 alloy is amorphous and sample of Mg70Zn30 alloy has crystalline structure. Immersion tests of both samples have shown homogeneous progress of corrosion. The changes of a structure caused by calcium addition resulted in an increase of microhardness for sample Mg66Zn30Ca4 compared with the sample of Mg70Zn30 alloy. Research limitations/implications: Results of immersion tests are dependent of used fluid. In this paper used physiological (multielectrolyte) fluid to corrosion studies, which composition is similar to the electrolyte composition of the blood plasma. Chemical composition of fluid used in corrosion studies could be affected to results of studies. Therefore it is appropriate to carry out comparative studies such as electrochemical corrosion studies. Practical implications: Mg-based alloys can be applied as the medical implants. The chemical composition of the samples Mg66Zn30Ca4 and Mg70Zn30 was chosen, because they meet the requirements of a biodegradable material, that is, material, which after completing their stability function will dissolve in the body of the patient without the harmful effects on health. Originality/value: Crystalline and amorphous magnesium alloys are examined as a material for biodegradable medical implants. This new concept is an alternative to previously used conventional implant materials. New concept doesn’t require re-operation, and allows foreign object to remain in the human body.

3

Planned obsolescence – today’s engineerind dilemma

Sakiewicz P., Nowosielski R., Pilarczyk W., Cesarz K.

Selected Engineering Problems

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2012

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nr 3

185--188

EN

Planned obsolescence (PO) is a policy of planning, designing and manufacturing products with limited serviceable life. It has become an indispensable companion for today's economy, causing a lot of ethical and ecological controversy and stands in opposition to the strategy of sustainable development. The article presents environmental hazards resulting from the application of this strategy, draws attention to the widespread use of PO, with particular focus at the electronics industry. The range of activities and procedures used in the design and manufacture of products resulting from planned obsolescence was described. It was found that this strategy determinates the way of future business, obliging the engineers to design and produce goods according to planned obsolescence guidelines. This strategy brings profits to corporation, not paying attention to consumers and the environment.

4

Improvement of the enterprise based on model of OSH management system

Nowosielski R., Spilka M., Cesarz K.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 51, nr 1

39--46

EN

Purpose: The article examines the concept and the way to meeting the requirements implemented health and safety management system in industrial enterprise like Coking Plant. Based on analysis proposed improvements, which would aim to improve working conditions in the company. Design/methodology/approach: The proposed improvements are designed for specificity of work, production scale and nature of possible threats in the analyzed enterprise. Findings: The analysis showed that health and safety management system is implemented with PN-N 18001. Due to the large number of possible threats that may arise during the processing of coke reported a slight decrease in accidents at work and occupational diseases. It is therefore necessary to implement improvements to the already functioning occupational health and safety management system in the enterprise. Research limitations/implications: The proposed changes to decrease accidents at work, which in will turn enhance the safety of the selected company. Practical implications: Implementation of the improvements will increase the awareness of staff in relation to existing threats. Improvements that were proposed did not require large financial outlays and changes in the organization and working time positions. However, in big companies such as Coking Plant, even the smallest step towards improving safety at work is important and desirable. Originality/value: Continuously improving the health and safety management system to improve working conditions.