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In this paper, porous NiTi intermetallic was synthesized via a modified thermal explosion (TE) method, utilizing Ni (74 μm, 38 μm, 5 μm, 100–200 nm) and Al element powders as raw material. The exothermic behavior and phase transition of porous NiTi intermetallic compounds were studied. The results showed that with the refinement of Ni particle size, the heat release decreased, and the Ti-74 μm sample was the product of two eutectic reactions. Their mechanical properties were verified by the Vickers hardness tester and universal testing machine, and the corrosion behavior of porous NiTi intermetallic compounds in phosphate-buffered saline (PBS) solution was studied by electrochemical tests. Among them, Ti-5 μm exhibits the most homogeneous microstructure and favorable mechanical properties, which has a porosity of 31.7 % and a compressive strength of 321.71 MPa. However, corrosion resistance is sacrificed due to the high open porosity. This study holds great promise for precise control microstructural characteristics and optimization of mechanical and electrochemical properties of porous NiTi intermetallics. • Porous NiTi intermetallic compounds were sintered by a rapid TE method. • The refinement of the particle size will limit the heat release of the TE reaction. • The prepared NiTi has a porosity of 31.7 % and a compressive strength of 321.71 MPa. • Reducing porosity contribute to improving corrosion resistance. [ABSTRACT FROM AUTHOR]

• B2 phases in Al 0.3 CoCrFeNi HEAs are purposely controlled by annealing treatment. • Effect of B2 phases on corrosion resistance of Al 0.3 CoCrFeNi HEAs is studied. • The B2 phases deteriorate the pitting corrosion resistance of Al 0.3 CoCrFeNi HEAs. • B2 phases act as preferential pit nucleation sites and facilitate pit propagation. The corrosion resistance of Al-Co-Cr-Fe-Ni high entropy alloys (HEAs) is probably affected by B2 phases. In this paper, the effect of B2 phases on the corrosion behavior of Al 0.3 CoCrFeNi HEAs in 3.5 wt% NaCl solution is clarified in this paper by purposely controlling the formation of B2 phases using annealing treatment. The microstructure characterization reveals that the content of (Al, Ni)-rich and Cr-poor B2 phases increases and the electrochemical measurements show that the pitting corrosion resistance is deteriorated as the annealing temperature decreases. Accordingly, the B2 phase is confirmed to be detrimental to the corrosion resistance of Al 0.3 CoCrFeNi HEAs. It can be attributed to the preferential dissolution of B2 phases causing easier pit initiation, which is evidenced by the corrosion morphology observation and scanning Kelvin probe force microscopy measurements, and to the slower repassivation rate leading to easier pit propagation, as demonstrated by the quantitative analysis of potentiostatic polarization curves. [ABSTRACT FROM AUTHOR]

• Similarity between natural corrosion and accelerated experiment is evaluated. • The number and location of corrosion peaks are statistically consistent. • Corrosion configurations are very likely to be similar within the rear region. • Reversal of corrosion configuration in the front region is possible. Concrete structures can be seriously deteriorated by the corrosion of steel reinforcement lasting for decades under realistic environment. It is still controversial whether and how the natural corrosion can be reasonably accelerated in experimental simulation. This paper focuses on the probabilistic similarity of corrosion pattern by comparing the normalized configuration of natural corrosion and galvanic accelerated experiment. The former is obtained by conducting the Monte-Carlo simulation of the electrochemical process based on the meso -scale model of concrete, whist the latter is analysed using digital image correlation method. The results indicated that their number and location of corrosion peaks are statistically consistent. The configurations of corrosion are very likely to be similar within the rear region of steel reinforcement in most cases, whereas possibly to be reversed in the front inward region and front outward region. The similarity is affected by the geometry of designed specimen and humidity of simulated environment. [ABSTRACT FROM AUTHOR]

• Effect of oxygen impurity on corrosion of a Zr-based BMG in H 2 SO 4 and NaOH is studied. • Oxygen impurity has no effects on the corrosion in 0.5 M H 2 SO 4. • Oxygen impurity can improve the corrosion resistance in 0.5 M NaOH. • Oxygen-induced annihilation of free volume may account for the inhibited corrosion. Effects of unavoidable oxygen impurity in industrial-grade Zr-based bulk metallic glasses (BMGs) on their properties are the issues that must be considered. The studies on oxygen-related corrosion behaviors of Zr-based BMGs are rarely reported. This paper aims to clarify the effects of oxygen impurity on corrosion of the as-cast Zr 61 Ti 2 Cu 25 Al 12 BMGs in 0.5 M H 2 SO 4 and 0.5 M NaOH solutions. The results show that oxygen impurity has no effects on the corrosion in 0.5 M H 2 SO 4 , but is unexpectedly beneficial for improving the corrosion resistance in 0.5 M NaOH by inhibiting the cathodic reaction. The latter phenomenon could be correlated with the oxygen-induced annihilation of free volume. The finding herein further confirms that oxygen impurity is not harmful, even beneficial, for corrosion resistance of industrial-grade Zr 61 Ti 2 Cu 25 Al 12 BMGs. [ABSTRACT FROM AUTHOR]