Ni-Cr-Mo alloys have been widely used as fixed dental prostheses. Recast process influence on corrosion behavior of Ni-Cr-Mo dental alloy in simulated physiological serum has been investigated using chemical and electrochemical techniques. Ni-Cr-Mo alloy recast by induction (induction) or by blowtorch (torch) has exhibited similar dendritic structures with wide and precipitate grains in their boundaries. The torch alloy has presented good corrosion resistance in physiological serum. Passivation process provides this corrosion resistance. Passivation of Ni-Cr-Mo alloy is often attributed to the formation of a thin and compact layer of chromium oxide (Cr₂O₃). This film is self-limiting because it acts as a barrier to the oxygen transport and metal ions. This film stability will depend on its solubility to the working temperature. Different recast procedures change electrochemical parameters as stabilizing potential in open circuit, current density and passivation interval

The pit morphology and growth kinetics of commercially pure aluminium in naturally aerated NaCl solutions were studied using an image processing method based on reflected light microscopy. In order to distinguish between pits and pre-existing cavities, metallographic examination and statistical analysis were carried out before and after corrosion testing. The results show that the pit shapes and sizes are more dependent on the immersion time than the chloride concentration. Pits are predominantly hemispherical, but they undergo reasonable geometric transitions associated with increased immersion time and occur without significant depth variation. The role of chloride ions is more closely associated with the pit nucleation phenomenon

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Zinc alloys coatings formed with elements of group VIIIB are promising because they display similar properties and protect steel by galvanic action. The Zn-Ni alloy is remarkable by showing improved mechanical properties and better corrosion resistance when compared to zinc coatings of similar thickness, also can be applied at higher temperatures. In this work, electrodeposits of Zn, Zn-12%Ni, obtained upon SAE 1010 steel from commercial alkali baths, were treated by blue chromatization and characterized according to mechanical properties and morphology. Studies were carried out by using measures of hardness, roughness, SEM, EDS and XRD. Among the studied electrodeposits, alloys treated by chromatization showed higher corrosion resistance and Zn-Ni electrodeposits showed higher value of roughness and hardness, while zinc coating had results similar to the steel substrate By means of XRD, it was found that electrodeposits are crystalline, being identified in Zn-Ni alloy the presence of the phases (Ni 5 Zn 21) and (Ni 3 Zn 22), which are responsible for its higher corrosion resistance.

In this work, the objective was to correlate anisotropy with the mechanical and microstructural behavior of two high strength steels used in vehicle production in order to obtain variables to alter future manufacturing processes in order to obtain steels with a lower elastic return, known as springback effect, which means geometric changes suffered by the part at the end of the plastic deformation process, after the release of the forces applied by the stamping tool and this causes dimensional failures that compromise the production. In this research, biphasic steel and one low carbon steel were evaluated, being Docol_DL800 and LC200 their trade names, respectively. Tensile tests and three-point bending in air were performed to determine the mechanical properties and behaviors and these results were compared with those obtained by computational simulation using the finite element method and were also correlated with microstructural data from the backscattered electron technique. The results indicate that biphasic steel has a higher hardening allowing a greater springback effect due to its microstructure with ferrite and martensite, high grain refinement, greater amount of elastic residual energy and a lower degree of disorientation after mechanical conformation, creating the effect Bauschinger. Already the steel LC200 presented a smaller degree of springback thanks to the more isotropic hardening due to the increase in the degree of grain disorientation after the conformation. Thus, it was concluded that the manufacturing processes of these steels should seek to combine high mechanical strength with a more isotropic behavior.