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The alloying of the zinc with some additional elements in specific quantities could be reliably used in the hot-dip coating process. These elements form specific intermetallic compounds that conferred substantially improved performance to the end-product specially by improving of the corrosion resistance. The paper presents the research that has developed to analyze the influence of aluminum, bismuth and tin like alloying elements added in the zinc on corrosion resistance of galvanized steels. Steel samples were galvanized by the hot-dip method in micro-alloyed zinc baths. The influence of the alloying elements on the formation of the different phases and on the diffusion process is discussed. The corrosion experiments were carried out in a simulated environment of accelerated corrosion conditions. The kinetics and the mechanism of corrosion of the samples were studied in correlation with the effect of alloying elements on nature and characteristics of protective layers.

No major adverse outcomes were related to PCSA postoperatively. Nevertheless, continuation of home positive airway pressure therapy during anesthesia recovery was useful in one patient who had cirrhosis and postoperative hypoxemia.

The paper presents the research that has developed to clarify the zinc microalloying process with nickel, aluminum, bismuth and tin. We have analyzed the parameters and factors that influenced the dissolution process of alloying solid elements in the liquid phase (zinc bath) in respect to compositional controlling process. In accordance we analyzed the most important parameters that influenced this process. There have established the optimum making technology of the zinc alloys used into hot dip galvanized process and also the correction technology of the bath composition into continuous process.

This study presents the result of the researches regarding the obtaining of NiTi alloy through powder metallurgy (PM) as a possible alternative to present technologies (melting through induction in vacuum—MIV and re-melting with electric arch in vacuum—VAR). The researches made by the authors have aim at the obtaining of Ni-Ti materials with fine grain or ultrafine grain through powder metallurgy techniques, starting from ordinary metallic powders of Ti, Ni, Cu, with grain size less than 100 micrometers, and also using processing through severe plastic deformation (HPT — high pressure torsion). The fabrication through PM has an important advantage because a product requires low processing subsequent considering that it can get with sizes and shape very similar to the final ones, which is not negligible if one takes into account that the alloys Ni-Ti do not excel on cutting processability. Cylindrical samples were produced by cold uniaxial compression, at the specific pressure of 600 MPa, dosed in a proportion of 52.5 % Ni + 43.5 % Ti + 4.0 % Cu, mass composition. The compressed samples, after the sintering in vacuum and severe plastic deformation have been characterized by X-ray diffraction (XRD) , differential scanning calorimetry (DSC) and optical microscopy.