Copper-based alloys with the addition of Al present excellent properties and can be considered a proper choice for applications as contact materials based on their good strength and fret resistance. Cu-Al alloys are used in different systems parts as bearings, gears and worm gears. The intention is to replace steel materials with new copper-based materials for parts that work in a possible explosive environment to reduce the possibility of spark appearance. Copper-berilyum alloys are known as non-sparking alloys and are used in different tools obtaining for environments with possible explosive gaseous. Results from the obtaining and analysis of a new alloy based on CuAlBe are given. The material was melted in a vacuum induction furnace from CuBe master alloy and high purity aluminium and cast into a metallic die. The alloys obtained were analyzed using EDS – energy dispersive spectroscopy for chemical composition, OM-optical and SEM-electronic microscopy for the microstructure, and the electro-corrosion resistance was tested using linear Tafel diagram and cyclic potentiometry.

The Fe-based alloy with manganese led to the appearance of new austenitic alloys, with the antiferromagnetic property pursued, resulting in compatibility with the magnetic field as that of magnetic resonance imaging. The corrosion resistance behavior of the biodegradable Fe-Mn-Si alloy was analyzed in a thermostatic chamber at 37±1°C for 24, 48 and 72 hours by immersing in Ringer solution. Also, the cast and laminated samples were subjected to electro-corrosion tests using a potentiostat equipment. Linear and cyclic potentiometry is presented for characterize the corrosion behavior of the experimental samples in electrolyte. Due to the interaction between the alloy and the liquid medium a change in the solution pH was observed. Structure analysis and chemical composition details of the surfaces were obtained using electron scanning microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS).

Biodegradable materials represent a new class of biocompatible materials with applications in many medical cases where the support must be provided only for a certain period. In this article obtaining of ZnMgY alloy is presented along with some basic characteristic investigations like chemical composition (energy dispersive spectroscopy – EDS), microstructure (optical microscopy – OM and scanning and electron microscopy – SEM), immersion behavior in 10xDPBS (Dulbecco Phosphate Buffer Saline) solution (mass loss and surface degradation), electro-corrosion behavior (potentiostat with a three electrodes cell) and micro-hardness of the experimental alloy compared to cast Zn and ZnMg materials. The results present an improvement of micro-hardness of Zn by alloying with Mg and Y and a modification of corrosion resistance.

Explosion protection is of particular importance for safety as explosions also endanger the health of workers due to the uncontrolled effects of flames and pressure, the presence of harmful reaction products and the consumption of oxygen in the ambient air breathed by workers. CuAlBe alloy is proposed as a solution for mechanical actuators such as gears that work in environments with possible explosive atmosphere. Made of CuBe master alloy and pure aluminum in a induction furnace the material present large grains in melted state. After the hot rolling (heated 600s at 900°C) of the ingots small variation of chemical composition was observed based on the oxidation of the material, appearance of small cracks on the edges and a preferential orientation of the grains along the lamination direction. Scanning electron microscopy (SEM) was used to characterize the microstructural states of CuAlBe as laminated and heat treated states.

In this case ceramic layers from Metco ZrO2 and Al2O3 powders mixture (25/75; 50/50 and 75/25) were obtained through atmospheric plasma spraying (APS) after five passes on low carbon steel substrate. The sample surfaces mechanically grinded (160-2400) before and after ceramic layer deposition. Powder’s mixtures and the surface of ceramic thin layers were analyzed through: scanning electron microscopy (SEM). In order to understand the effect of surface wettability of the ceramic layers, before and after grinding the surface, three different liquids were used. Experimental results confirm the modification of the steel substrate surface characteristic from hydrophilic to hydrophobic when the ceramic layer was deposited. Surface free energy of hydration increases for all the samples with zirconia percentage addition before polishing process.