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The influence of the chemical composition and structural state of Zn–Ti alloys on corrosion behaviour and mechanical properties was studied. Zn-based alloys were investigated, more precisely, pure technical Zn and Zn with 0.10, 0.25 and 1.00 wt.% Ti. The microstructure and chemical composition of these materials were analysed using light optical microscopy (LOM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The chemical composition of the alloys and the surface after immersion were analysed using an EDS detector from Bruker. The alloys' electro-chemical corrosion resistance was further investigated through linear (LP) and cyclic (CP) potentiometry and open-circuit potential (OCP) analysis. A tensile/compression equipment (Instron 34SC-5) was used to determine the compression behaviour. UMT testing equipment was used to determine microhardness (by Rockwell indentation) and COF vs. length. For percentages higher than 0.25 wt.% Ti, the formation of a primary TiZn16 intermetallic compound in the (α-Zn + TiZn16) eutectic matrix was observed, a slight influence of TiZn16 on the Zn corrosion resistance results, and a greater influence on the mechanical properties was confirmed. [ABSTRACT FROM AUTHOR]

The emergence of incremental sheet forming has led to the development of innovative manufacturing techniques that possess great adaptability and hold the potential to provide substantial economic advantages in the realms of advanced technologies and low‐volume production. In this study, specialized analyses are conducted to determine the structure and morphology of the surfaces produced after single‐point incremental sheet forming (SPISF). The material subjected to SPISF is Al 3003. For the material forming, two types of tools, one uncoated and one coated with titanium nitride (TiN), are used. It is observed that the TiN‐coated tool yields the most favorable roughness outcomes and also reduces the values of the forming components. According to the scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis, the deposition of the TiN on the tool is uniform, thus the results relate to the surface roughness and not only justified. [ABSTRACT FROM AUTHOR]

This study evaluates the mechanical performance of ambient-cured fly ash-based geopolymer composites reinforced with recycled glass fibers. First, the Taguchi method was used to optimize the fly ash-based geopolymer matrix, considering the Na:Al ratio, liquid:solid ratio, and sand content. Secondly, two types of glass fibers (25 mm length and 60 mm length) have been introduced in three different amounts (1, 2, and 3 wt. %, respectively) in order to improve the flexural strength of the developed composites. Compressive strength tests and the three-point flexural method were conducted to demonstrate the effect of fiber type and amount on the mechanical performances of fly ash-based geopolymers, while microstructural analysis was used to reveal the improving mechanism caused by the bridging effect of reinforcing fibers. Experimental results showed that Na:Al of 0.75, NaOH concentration of 10.85M, Na2SiO3:NaOH solution of 4:1, and Sand:Fly ash of 1:1 are the optimum parameters for compressive strength, while Na:Al of 0.5, NaOH concentration of 2.96M, Na2SiO3:NaOH solution of 2:1, and Sand:Fly ash of 1:4 exhibit the highest flexural strength, despite the aging time (14 or 28 days). Moreover, the addition of recycled glass fiber led to an increase of up to eight times in flexural strength due to the bridging effect. However, the compressive strength slightly decreased for all mixtures due to an increase in porosity. The microstructural analysis confirmed a homogenous matrix with high adhesion to the surface of glass fibers. [ABSTRACT FROM AUTHOR]

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel does not readily corrode, rust or stain with water as ordinary steel does, but despite the name it is not fully stain-proof, most notably under low oxygen, high salinity, or poor circulation environments. It is also called corrosion-resistant steel or CRES when the alloy type and grade are not detailed, particularly in the aviation industry. There are different grades and surface finishes of stainless steel to suit the environment the alloy must endure. Stainless steel is used where both the properties of steel and resistance to corrosion are required. A stainless steel material suffers a generalized corrosion after his immersion in sea water during 30 days. The environment is a closed considered space and do not consider the biological effects on the metallic material surface. The liquid influence on the metallic element surface was analzyed through scanning electrons microscopy (SEM) with 2D and 3D considerations and by energy dispersive X-ray analyze (EDAX) for chemical insights. The nature of chemical compounds appeared on the surface was also established and considered for further corrosion effects investigations. [ABSTRACT FROM AUTHOR]

The corrosion products of high strength low-alloyed steel and of cast iron, maintained a prolonged period in natural seawater, were analyzed. A part of the corrosion products are soluble compounds of divalent and trivalent iron, the iron dissolution being accelerated when divalent ions are formed and in the case of the aerated seawater. The solid corrosion product formed during corrosion in seawater is principally oxy-hydroxide (FeOOH), but were identified small quantities of Fe2O3, Fe3O4 and some crystals of sodium chloride polluted with calcium and magnesium. The FT-IR measurements have pointed out that the FeOOH have a poly-molecular structure. In dynamic heating conditions the decomposition of solid rust take place by three distinct processes: adsorbed water elimination, dehydroxylation of the FeOOH to amorphous Fe2O3 and crystallization of Fe2O3. [ABSTRACT FROM AUTHOR]