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Super-hydrophobicity inspired by natural water-repellent surfaces has received tremendous attention for surface functionalization of metallic materials in many applications. Problems of corrosion and/or contamination that happens on the surface can be partially solved as the material obtained super-hydrophobicity. Appropriate surface pattern and low surface energy are the two key factors that can realize super-hydrophobicity. In the present paper, laser surface texturing (LST) followed by decoration of Hexadecyltrimethoxysilane (HDTMS) was conducted to manipulate the super-hydrophobicity and corrosion resistance of AISI 316 stainless steel (SS) on the surface. Scanning electron microscopy (SEM) and an ultra-depth field microscope were employed to characterize the surface morphologies of the received samples before and after corrosion tests. Corrosion resistance and super-hydrophobicity for the related samples were investigated using electrochemical tests and water contact angle measurements. It was found that various surface patterns differed with intervals (250, 150, 80, and $d=50\mu$m,) between two micro-dimples have formed on 316 SS sample surfaces after LST treatment. The surface roughness values gradually increased with the decrease of interval. The 316 SS samples obviously reduced surface energy values after HDTMS decoration. In simulated haze solution, electrochemical tests demonstrated that the 316 SS sample treated with $\mathrm{\text{HDTMS}}+\mathrm{\text{LST}}$ (HT-316 SS, $d=50\mu$m) exhibited lower corrosion and higher corrosion potential current density than the smooth 316 SS (S-316 SS), $\mathrm{\text{HDTMS}}+\mathrm{\text{S}}$-316 SS (HS-316 SS), and LST 316 SS (T-316 SS, $d=50\mu$m) samples. As expected, the HT-316 SS ($d=50\mu$m) exhibited the highest water contact angle of 155.85^∘ as compared to HS-316 SS and other HT-316 SS samples. Meanwhile, the superhydrophobic surface of HT-316 SS ($d=50\mu$m) exhibits super-oleophilic and self-cleaning properties.

Microstructural evolution during compressive deformation of a meta-stable austenitic stainless steel has been investigated using an electron-backscattered diffraction (EBSD) technique. A local area tracking method has been adopted in order to observe the successive changes in local microstructures during the compression. The local microstructures could be observed in-situ from this method without using any in-situ stage, in addition to a precisely-controlled real time deformation process. Successive development of grain orientation spread, grain boundary misorientation and deformation-induced phase in the local areas of interest were successfully investigated from this method.

The austenitic stainless steel specimens with a micro-crystalline/nanocrystalline bimodal structure (micro-nanostructure) were produced by aluminothermic reaction casting method, and the tensile tests and in situ tensile tests were performed. It is found that the stress–strain curve displays the secondary yielding. The uniformly distributed mixed-grain microstructure of the micro-nanostructure is responsible for its strength and toughness. Based on the Hall–Petch relationship of a single-scale and considering the volume fraction of the micro-nanostructure, a mathematical model between the grain sizes and the yield strength is established. The model has a good accuracy when compared with the actual results.

Combined plasma nitriding and surface texturing approach were conducted on 316 stainless steel to enhance the tribological performance. Five different surfaces (316 substrates, plasma-nitrided 316, surface-textured 316, plasma-nitrided surface-textured 316, and surface-textured plasma-nitrided 316) were investigated. The tribological behaviors were studied using a ball-on-disk rotary tribometer against counterparts of Si₃N₄ balls in the air and under oil lubrication conditions. The results were analyzed from the aspects of friction coefficient, mass loss, and surface morphology about the tested specimens. The results presented that the frictional properties of the surface of plasma-nitrided surface-textured 316 were optimal under both friction conditions. Under dry friction conditions, the influence of plasma nitriding on mass loss was greater than that of surface texturing. Under oil lubrication conditions, the influence of surface texturing on mass loss was greater than that of plasma nitriding, and the processing sequence of surface texturing and plasma nitriding had little effect on the mass loss. The better wear resistance of plasma-nitrided surface-textured 316 resulted from the following aspects: first, the nitriding layer improved the surface hardness of the material. Secondly, the surface texture can capture the debris under dry friction conditions and provide continuous lubrication under oil lubrication condition.

Tube hydroforming (THF) is an unconventional manufacturing technique that uses pressurized fluid in place of conventional punches to deform the tubular blank into the desired shape. In THF process tubular blank is deformed it into the final shape by applying fluid pressure mostly by water using water intensifier through axial punches. Tube hydroforming is mainly used to produce hollow components using tubular blank which find applications in automobile industry, particularly for exhaust systems. The formability of Austenitic stainless steel tubes as function of microstructure is not focused much in literature. Hence, in this study, formability of Austenitic stainless steel tubes is studied as a function of boundary conditions and bulge width (L/D ratio) and correlated with microstructure. Microstructure resulting in axial feed condition showed better formability than microstructure resulting in fixed feed condition. Similarly, formability and fracture behavior of tube predicted with finite element-based simulation using PAMPSTAMP 2G solver found results, particularly bulge height and fracture location are in good agreement with experimental values. The observed fracture mode noted was ductile both for axial feed condition and fixed feed condition as the fracture consists of voids and micro voids. Fracture location was in base metal just, besides, weld line for axial feed condition and fracture location was in base metal which is little away from weld line for fixed feed condition.

In this research, ductile damage development and martensitic strain-induced phase transformation in plastic behavior of AISI 304 austenitic stainless steels at cryogenic temperatures are investigated. Nonlinear behavior of hardening and damage evolution could be observed in two-phase material as the result of strain-induced phase transformation. A simplified constitutive model for monotonic loadings, combining the effects of phase transformation and isotropic damage evolution has been introduced. Numerical analysis via implementing the model by means of a user subroutine UMAT in Abaqus/Standard is carried out. In addition, experiments including loading-unloading tensile test and X-ray diffraction test at cryogenic temperature 77K have been conducted to identify the parameters of the model and to compare with numerical results.

Stainless steels are attractive due to its high strength, high chemical stability, low gas permeability and wide selection of alloys. However, stainless steels are prone to corrosion where SO4^2- and F^- are released from the membrane in the PEFCs, which, as a result, will shorten the age of the bipolar plates and exert a negative influence on the function of the cells. Therefore, great attention is given on high-nitrogen austenitic stainless steels (HNASS) which have lower costs and good localized corrosion resistance. The effects of the different F- concentration on the corrosion behavior in the high nitrogen austenitic stain steel were investigated through polarization curve measurement and electrochemical impedance spectroscopy. The results show that the corrosion resistance of the experimental steel is the best in the 0.05 mol/L SO42- (pH 5.5) + 2 ppm F- solution. As the F- concentration increases, the passivation film of the experimental steel becomes thicker and denser, leading to stronger corrosion resistance.

Leak before break (LBB) is an important analysis method for insuring the structure safety and reliability of nuclear reactor. Now LBB technology is widely used in nuclear power plant design. It has a good development in foreign countries, but domestic research is relatively little. The study of crack propagation is core of LBB analysis. In this paper the LBB was analyzed for the pipes of the CEFR, which based on the A16 in RCC-MR. According to the analysis, the pipes we chose matched the LBB technique about the crack stability and the detecting of leak quantity, the time require from the beginning of the leak to the crack lose steady.

Microstructural evolution during compressive deformation of a meta-stable austenitic stainless steel has been investigated using an electron-backscattered diffraction (EBSD) technique. A local area tracking method has been adopted in order to observe the successive changes in local microstructures during the compression. The local microstructures could be observed in-situ from this method without using any in-situ stage, in addition to a precisely-controlled real time deformation process. Successive development of grain orientation spread, grain boundary misorientation and deformation-induced phase in the local areas of interest were successfully investigated from this method.