Surface studies and corrosion products layers of amorphous magnesium based alloys in Ringer’s solution
Institute of Engineering Materials and Biomaterials, Department of Nanocrystalline and Functional Materials
and Sustainable Proecological Technology, The Faculty of Mechanical Engineering, Silesian University of Technology
Department of Chemistry, Inorganic Technology and Fuels, Faculty of Chemistry, Silesian University of Technology
Institute of Physics, Department of Solid State Physics, Faculty of Mathematics, Physics and Chemistry, University of Silesia
The aim of the work was the surface and the layers of corrosion products investigation in terms of structure and chemical composition of the amorphous magnesium alloys according to immersion time in chloride environment at 37°C. The structure of the samples was analyzed by X-ray examinations. The study simulated conditions corresponding to human blood. During the tests the amount of evolved hydrogen was measured as an indicator describing the kinetics of the process. Testing solution and temperature (37°C) were selected due to the possibility of use Mg-based bulk metallic glasses for resorbable medical implants. It was found that the concentration of zinc in Mg68Zn28Ca4 and Mg64Zn32Ca4 alloys has very important influence on the corrosion process, structure and chemical composition of the corrosion products in chloride environment.
Keywords: amorphous magnesium alloys, immersion tests, corrosion products, hydrogen measurement.
Vol. 60, nr 6
CORROSION PROTECTION IN PRACTICE
Steel structures painted in the colours RAL 9006 and RAL 9007.
Experience with realization
VISTAL CONSTRUCTION Sp. z o.o., Gdynia
The article presents the experience of the corrosion protection of steel structures with high requirements decorative topcoats in the colors RAL 9006 and RAL 9007. It describes doubts concerning the visual evaluation of the coating. The article indicates possible proceeding scenarios in such contracts.
Keywords: colour evaluation, anticorrosion, steel structures
Vol. 60, nr 6
The degradation of concrete in the presence of domestic sewage
PK Cracow University of Technology, Faculty of Civil Engineering Chair
of Building Materials Technology and Structure Protection
The paper presents the effects of domestic sewage on concrete rings, which were used to build pumping stations. The tests were performed on samples of concrete and concrete corrosion products (sludge) that had been collected from existing and functioning sewage wells. The problem of the degradation of the concrete concerned several wells entire sewage system, and in that said faulty ventilation. The authors indicates, that the lack of proper ventilation can be a potential cause of the microclimate strongly aggressive in relation to the concrete. The study has used research on the chemical analysis of concrete as well as microscopic observations. Additionally, concrete strength tests were carried out in order to determine the effects and the scale of the observed changes due to biological corrosion in the aspect of the changes to mechanical features.
Keywords: sewage well, sulphate corrosion, sulphate bacteria
Vol. 60, nr 6