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The article examines common electrical installation mistakes in boatbuilding, revealing that many insurance claims stem from errors made by boat builders rather than modifications by owners. It also discusses the importance of adhering to international electrical standards (ISO 13297 and ABYC E-11) to prevent these issues and emphasizes the need for proper overcurrent protection and wiring practices to ensure safety and reliability onboard.

• The Fe-Cr-Ni-Mn-N austenitic stainless steel exhibits an exceptional mechanical property at 4.2 K with a high yield strength of 1.5 GPa. • The deformation nanotwinning, HCP ε-martensite transformation, dislocation slip with L -C locks and stacking fault formation which provided a marked contribution to the Fe-Cr-Ni-Mn-N alloy's ultrahigh strain hardening rate and outstanding strength at liquid helium temperature 4.2 K. • The Fe-Cr-Ni-Mn-N austenitic stainless steel displays outstanding cryogenic mechanical properties through a progressive synergy of deformation mechanisms leading to exceptional strength which provides a new insight into the commercialized development of high-performance alloys for cryogenic applications. We report the mechanical performance and microstructural characteristics of a Fe-Cr-Ni-Mn-N alloy at cryogenic temperatures. The exceptionally high yield strength of 1.5 GPa combined with a high strain-hardening rate and no deterioration in ductility at 4.2 K was displayed. The evolution of deformation microstructure was examined using electron backscatter diffraction (EBSD), the transmission Kikuchi diffraction (TKD), high-resolution transmission electron microscopy (HRTEM), and aberration-corrected scanning TEM (STEM). The deformation microstructure mainly consisted of dislocation slip with L -C locks, {111} stacking fault formation, {111} deformation nanotwinning, and FCC → HCP shear transformation at 4.2 K. The occurrence of FCC-HCP shear transformation inside/near {111} twins to form γ-γ tw -ε dual-phase structure induces a dynamic Hall-Petch effect that promotes the strain-hardening rate and enhances the strength-ductility combination. We believe that this alloy displays outstanding damage tolerance through a progressive synergy of deformation mechanisms leading to exceptional strength which provides a new insight into the commercialized development of high-performance alloys for cryogenic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• A dual-functional TiO 2 /CdZnS/ZnS heterojunction photoanode is fabricated. • The TiO 2 /CdZnS/ZnS photoelectrodes show desirable PECCP and anti-biofouling performance. • The synergistic mechanism of PECCP and anti-biofouling is proposed. The low photoelectric conversion efficiency of photoelectrode is an important factor that limits the application in photoelectrochemical cathodic protection (PECCP) field for marine anti-corrosion of metallic structures. In this work, a photoelectrode of TiO 2 /CdZnS/ZnS triple-phase heterojunction was fabricated by loading the narrow-band CdZnS associated with the broad-band ZnS via hydrothermal and continuous ion layer adsorption methods, respectively. The composite of CdZnS enhances the photoelectric conversion ability of TiO 2 , while the ZnS composite can prevent the CdZnS from photo-corrosion and suppress the spillover of the photogenerated electrons. The three-phase heterostructure effectively improves the PECCP performance on 316 L stainless steel (SS) under simulated solar irradiation, especially in 3.5 wt% NaCl solution without the sacrificial agent. In addition, the prepared TiO 2 /CdZnS/ZnS photoelectrode also performs anti-biofouling effect evidenced by the high removal efficiency of Pseudomonas aeruginosa (P. aeruginosa), which can be attributed to the oxidizability of photogenerated holes. The TiO 2 /CdZnS/ZnS triple-phase heterojunction with desirable performance is a promising semiconductor material for the applications of PECCP and anti-biofouling. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Selective oil removal from water is a critical problem in the realm of environmental science and engineering. Metallic meshes are commonly used as potential oil–water separators due to their low cost and good mechanical properties. Meshes with selective wettability can effectively remove oil or water from their mixtures easily using gravity-based filtration. In this work, a mechanically robust Ni-WS 2 based superhydrophobic stainless steel mesh (SHSM) has been developed via one-step electrodeposition. The surface morphologies, surface roughness, phase composition, and wettability were studied using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), X-ray diffraction (XRD), and Water Contact Angle (WCA) measurements respectively. A high water contact angle of 169.5° with excellent superhydrophobic and superoleophilic properties was achieved by tuning the surface morphology of the mesh. The oil/water separation performance of the developed SHSM was studied and the efficiency was greater than 98% even after multiple uses. Further, the SHSM is highly corrosion-resistant and exhibits self-cleaning properties with excellent mechanical and chemical stability against strong acidic/alkaline solutions. Thus, the developed multifunctional SHSM demonstrates its potential at industrial-level applications of oil–water separation under harsh environments. [ABSTRACT FROM AUTHOR]

• The decomposition of ceramic particles in LPBF-fabricated metal matrix composites has been reported for the first time. • Direct evidence showing the decomposition of TiC using Atom Probe Tomography has been provided. • Heat treatment was conducted to confirm the supersaturation of Ti and C atoms in 316L matrix. • A hierarchical distribution of TiC was observed. Recent advancements have shown the effectiveness of strengthening 316L with TiC particles addition through the laser powder bed fusion (LPBF) process. However, the question remains whether TiC undergoes decomposition into Ti and C atoms, primarily because of the challenges associated with measuring C at low concentrations. In this study, we employed atom probe tomography (APT) to provide evidence of decomposition by observing the presence of Ti and C atoms in the 316L matrix. The fast cooling rate of the LPBF process results in the supersaturation of Ti and C in the 316L matrix. Adding 3 wt% TiC particles increased the yield strength of LPBF-processed 316L from 599 MPa to 832 MPa. The subsequent annealing treatment resulted in the formation of more TiC nanoparticles as a result of precipitation from the supersaturated Ti and C in the 316L matrix. Consequently, the yield strength was further enhanced to 959 MPa after annealing at 700 °C for 1 h. This study marks the first direct demonstration of the decomposition of TiC in metal matrix composites. [Display omitted] [ABSTRACT FROM AUTHOR]

• Mechanical properties of LPBF 17-4 PH linked to microstructure and residual stress. • 17-4 PH austenite volume fraction increased after solution annealing and quenching. • Solution annealing followed by ageing did not lead to precipitation strengthening. • Dynamic austenite to martensite transformation contributed to the work hardening. • Residual stress is more strongly affected by scanning pattern than energy density. 17-4 precipitation hardening (PH) stainless steel is a multi-purpose engineering alloy offering an excellent trade-off between strength, toughness, and corrosion properties. It is commonly employed in additive manufacturing via laser powder bed fusion owing to its good weldability. However, there are remaining gaps in the processing-structure-property relationships for AM 17-4 PH that need to be addressed. For instance, discrepancies in literature regarding the as-built microstructure, subsequent development of the matrix phase upon heat treatment, as well as the as-built residual stress should be addressed to enable reproducible printing of 17-4 builds with superior properties. As such, this work applies a comprehensive characterisation and testing approach to 17-4 PH builds fabricated with different processing parameters, both in the as-built state and after standard heat treatments. Tensile properties in as-built samples both along and normal to the build direction were benchmarked against standard wrought samples in the solution annealed and quenched condition (CA). When testing along the build direction, higher ductility was observed for samples produced with a higher laser power (energy density) due to the promotion of interlayer cohesion and, hence, reduction of interlayer defects. Following the CA heat treatment, the austenite volume fraction increased to ∼35 %, resulting in a lower yield stress and greater work hardening capacity than the as-built specimens due to the transformation induced plasticity effect. Neutron diffraction revealed a slight reduction in the magnitude of residual stress with laser power. A concentric scanning strategy led to a higher magnitude of residual stress than a bidirectional raster pattern. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Surface coatings are an effective technique for mitigating fouling in heat exchangers. In this study, a stable polytetrafluoroethylene (PTFE) coating was prepared with improved corrosion resistance and CaCO 3 fouling inhibition rate. The prepared PTFE coating remains strongly stable even undergoing tape stripping, sandpaper abrasion, water impacting and immersion. The corrosion-suppression efficiency of the coating is 95.09 % compared to the stainless steel surface. Fouling tests reveal that the coating possesses an inhibition rate of 86.25 %, and it retains a high level of fouling inhibition rate even after 100 cycles of tape stripping and 400 mm of sandpaper abrasion. Additionally, molecular dynamics simulation was performed to gain insight into the anti-fouling mechanism of the PTFE coating. The results demonstrate the presence of two dense adsorption layers of water molecules in close proximity to the metal surface, which is found to be a crucial role in facilitating the adsorption of CaCO 3 ions due to their strong attraction (E interaction = -15.47 eV) towards the ions. In contrast, the weaker interaction (E interaction = -1.52 eV) between PTFE and water molecules results in the absence of dense water adsorption layers on the PTFE coating. Consequently, the PTFE coating effectively reduces the rate of ion adsorption on the metal surfaces in the initial stage of CaCO 3 fouling formation. [ABSTRACT FROM AUTHOR]

• The preheating was introduced into the friction stir welded 7Mn steel to tailor austenitic stability. • The unprecedented the product of strength and elongation was obtained in the as-preheated NZ. • The deformation behavior of austenite in the NZ was systematically studied. • Multiple strain hardening mechanisms in the NZ were revealed. The martensite often appears in the nugget zone (NZ) of friction stir welding (FSW) 7 wt.% Mn steel due to low austenite stability, deteriorating ductility and toughness. In this work, a 7 wt.% Mn steel was subjected to FSW, and preheating was used to tailor the austenitic stability to greatly improve the strength–ductility combination of the NZ. The austenitic deformation behavior and strain hardening mechanism in the NZ were systematically investigated. The microstructure of the as-welded NZ was composed of ultrafine blocky ferrite, austenite, and small amounts of martensite, whereas the as-preheated NZ contained ultrafine blocky ferrite and austenite, and the concentration of Mn in austenite was increased from 8.4 wt.% to 10.7 wt.%. This enhanced the austenitic stability, resulting in a significant increase in the volume fraction of austenite in the as-preheated NZ from 37.3% to 66.4%. The product of strength and elongation (PSE) in the as-preheated NZ increased dramatically from 42.6 GPa% to 67.1 GPa%, depending on a persistent high strain hardening rate (SHR). Multiple strain-hardening mechanisms were revealed. The austenite with enhanced stability can provoke sustained transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP) effects, and massive dislocation multiplication occurs during tension, resulting in strong strain hardening. [Display omitted] [ABSTRACT FROM AUTHOR]

• Proposition of "Bio-TWIP" alloy design strategy concept. • Construction of the preliminary empirical Bo ‾ – Md ‾ diagram of Zr alloys on the basis of d -electron method. • Designing of new ternary Zr alloys for stent applications as a prime example. • Studies of deformation mechanisms and essential biocompatibility in designed Zr alloys. This study proposes a novel strategy for the design of a new family of metastable Zr alloys. These alloys offer improved mechanical properties for implants, particularly in applications where conventional stainless steels and Co-Cr alloys are currently used but lack suitability. The design approach is based on the controlled twinning-induced plasticity (TWIP) effect, significantly enhancing the ductility and strain-hardenability of the Zr alloys. In order to draw a "blueprint" for the compositional design of biomedical TWIP (Bio-TWIP) Zr alloys—using only non-toxic elements, the study combines d -electron phase stability calculations (specifically bond order (B o) and mean d -orbital energy (M d)) with a systematic experimental screening of active deformation mechanisms within the Zr-Nb-Sn alloy system. This research aids in accurately identifying the TWIP line, which signifies the mechanism shift between TWIP and classic slip as the primary deformation mechanism. To demonstrate the efficacy of the TWIP mechanism in enhancing mechanical properties, Zr-12Nb-2Sn, Zr-13Nb-1Sn, and Zr-14Nb-3Sn alloys are selected. Results indicate that the TWIP mechanism leads to a significant improvement of strain-hardening rate and a uniform elongation of ∼20% in Zr-12Nb-2Sn, which displays both {332}<113> mechanical twinning and dislocation slip as the primary deformation mechanisms. Conversely, Zr-14Nb-3Sn exhibits the typical mechanical properties found in stable body-centered cubic (BCC) alloys, characterized by the sole occurrence of dislocation slip. Cell viability tests confirm the superior biocompatibility of Zr-Nb-based alloys with deformation twins on the surface, in line with existing literature. Based on the whole set of results, a comprehensive design diagram is proposed. [ABSTRACT FROM AUTHOR]

• 316 L powder and 17–4PH powder are mixed in different mass ratios to fabricate five types of stainless steels by directed energy deposition (DED) technique. • In the range of 0–70%, with the increase of 17–4PH powder content, the anisotropy and grain size of DED stainless steel are significantly reduced, and the mechanical properties are greatly improved. • P70 shows the weakest anisotropy and the best mechanical properties, which can be attributed to the cyclic phase transformation under cyclic reheating treatment and the multi-stage transformation-induced plasticity (TRIP) effect over a wide range of strains, respectively. Owing to the special layer-by-layer deposition process of directed energy deposition (DED), columnar coarse grains, produced by cyclic reheating with intrinsic directional heat flow along the building direction, are difficult to avoid. These grains result in strong anisotropic characteristics with poor mechanical properties, which restrict the application of DED products. This work proposes a novel fabrication strategy based on the cyclic-phase-transformation behavior, which can reduce the anisotropy and improve the mechanical properties of DED-printed stainless steel. Using this fabrication strategy, 316 L powder (austenitic stainless steel) and 17–4PH powder (martensitic stainless steel) were mixed in different mass ratios to fabricate five types of DED-printed stainless steels. Among the five samples, P70 (mixture of 70 wt% 17–4PH powder and 30 wt% 316 L powder) showed the weakest anisotropy and the best mechanical properties, which can be attributed to the cyclic phase transformation under cyclic reheating treatment and the transformation-induced plasticity (TRIP) effect over a wide range of strains, respectively. Compared with the pure 316 L printed material, the tensile test results of P70 showed that the yield strength (YS) and ultimate tensile strength (UTS) increased by 35.4% and 34.5%, respectively, whereas the uniform elongation (UE) and total elongation (TE) were improved by 63.9% and 31.4%, respectively. In addition, the strength–ductility balance (UTS × UE) increased by as much as 120.4%. The proposed fabrication strategy is expected to reduce the anisotropy in other materials that undergo cyclic-phase-transformation phenomena during additive manufacturing. [ABSTRACT FROM AUTHOR]

• Join NiTi and 316 L stainless steel sheets using resistance spot welding with Ni or Nb interlayer. • Uncover microstructural evolutions and mechanical properties of RSWed NiTi-steel joints. • Overcome the overall brittleness by suppressing the mixing with the help of a high-melting-point interlayer. • Provide first-hand observations on NiTi-steel RSW and new insights for dissimilar welding. Dissimilar welding of NiTi and stainless steel (SS) for multifunctional device fabrication is challenging due to the brittle nature of intermetallic compounds (IMCs) that are formed in the weld zone. In this work, Ni and Nb interlayers were applied for the resistance spot welding (RSW) of NiTi and SS to replace the harmful Fe 2 Ti phase and to restrict the mixing of dissimilar molten metals, respectively. Microstructural evolution and mechanical properties of the joints were investigated. It was shown that a conventional weld nugget was created in the absence of any interlayer in the welded joint suffering from traversed cracks due to the formation of brittle IMCs network in the fusion zone (FZ). By the addition of Ni from the interlayer, Fe 2 Ti dominated weld nugget was efficaciously replaced by Ni 3 Ti phase; however, the presence of the large pore and cracks reduced the effective joining area. The use of a Nb interlayer resulted in a fundamentally different joint, in which FZs at NiTi and SS sides separated by the unmolten Nb would suppress the mixing of dissimilar molten metals. Nb-containing eutectic structures with low brittleness formed at the interfaces, contributing to the enhancement of joint strength (increased by 38% on fracture load and 460% on energy absorption). A high-melting-point interlayer showed great potential to realize a reliable and high-performing RSWed NiTi-SS joint. [Display omitted] [ABSTRACT FROM AUTHOR]

• Circular oscillating deposition approach can eliminate defects and improve the properties of deposition layer. • Dense composite coatings forms good metallurgical bond with aluminum alloy. • Nano-micro scale TiC particles play a critical role in the improvement of wear and corrosion resistance. The poor wear and corrosion resistance of aluminum alloys has led to the easy failure of surface performance. In this work, composite coatings of TiC/martensitic stainless steel (TiC/MSS) on aluminum alloy are fabricated by a novel approach of circular oscillating laser for enhanced surface performance of aluminum alloys. The oscillation of laser leads to dense microstructure, and nano/micro scale TiC particles are formed simultaneously. The structure of coatings transforms from dendritic to ring-like with the addition of TiC, and the hardness of the substrate is increased by 4.5–7.8 times. The main wear form of coatings is adhesive wear. The refinement of microstructure and formation of multi-scale TiC have given rise to an increase in the resistance of the coating to plastic deformation, which reduces the degree of adhesion and improves wear resistance. Besides, the barrier effect of TiC particles to the electrolyte solution in the passive film gives rise to the drop in corrosion current density. The Cr-rich stacking faults can provide nucleation sites for the formation and growth of passive films with high continuity and stability, thereby improving the corrosion resistance of the coatings. The superior anticorrosion and wear resistance properties of the composite coatings in this work have emphasized the merits of oscillating laser in fabricating high-performance coatings and would enlighten the design of more advanced composite coatings. [Display omitted] [ABSTRACT FROM AUTHOR]

This article from Dirt Wheels magazine discusses various add-ons and accessories for the Can-Am Maverick R off-road vehicle. The author highlights the installation of a front grill kit made of aerospace-grade aluminum, a billet-aluminum side-mirror set with infinite tool-free adjustments, a ratcheting Y-strap and spare tire bag for cargo storage, and Rock Knockers to protect the rear trailing arms. The author also mentions using Rust-Oleum Sunburst Yellow touch-up paint to cover up pitting. The article provides information on where to purchase these products and includes photos for reference. [Extracted from the article]

• TiN is a highly effective grain refiner for additive manufacture (AM) of 316 steel. • δ-ferrite is the primary solid phase during AM of the 316 steel. • Grain refinement in the TiN-inoculated 316 steel was inherited from the refinement of δ-ferrite. • Grain refinement led to dislocation-based deformation mechanism in the TiN-inoculated 316 steel. • TiN inoculation led to the superior strength-ductility synergy in the 316 steel. As a potent grain refiner for steel casting, TiN is now widely used to refine γ-austenite in steel additive manufacturing (AM). However, the refining mechanism of TiN during AM remains unclear despite intensive research in recent years. This work aims to boost our understanding on the mechanism of TiN in refining the γ-austenite in AM-fabricated 316 stainless steel and its corresponding effect on the mechanical behaviour. Experimental results show that addition of 1 wt.% TiN nanoparticles led to complete columnar-to-equiaxed transition and significant refinement of the austenite grains to ∼2 µm in the 316 steel. Thermodynamic and kinetic simulations confirmed that, despite the rapid AM solidification, δ-ferrite is the primary solid phase during AM of the 316 steel and γ-austenite forms through subsequent peritectic reaction or direct transformation from the δ-ferrite. This implies that the TiN nanoparticles actually refined the δ-ferrite through promoting its heterogenous nucleation, which in turn refined the γ-austenite. This assumption is verified by the high grain refining efficiency of TiN nanoparticles in an AM-fabricated Fe-4 wt.%Si δ-ferrite alloy, in which δ-ferrite forms directly from the melt and is retained at room temperature. The grain refinement is attributed to the good atomic matching between δ-ferrite and TiN. Grain refinement in the 316 steel through 1 wt.% TiN inoculation not only eliminated the property anisotropy but also led to a high strain-hardening rate upon plastic deformation and thereby a superior strength-ductility synergy with yield strength of 561 MPa, tensile strength of 860 MPa and elongation of 48%. [Display omitted] [ABSTRACT FROM AUTHOR]

• Doping cerium (Ce) presents a promising pathway to synergistically improve the strength and ductility of stainless steels by AM. • The strengthening mechanism is contributed by strengthening effects of nanoscale precipitation (inclusion) and grain refining by doping Ce. • The improved misorientation angle of grain boundary and ameliorative coherency between the inclusion and matrix by doping Ce benefits the ductility. In this study, the PH13–8Mo stainless steel parts doped without and with cerium (Ce) were fabricated via laser powder bed fusion followed by post-heat treatment, and systematically compared in terms of microstructure, phase constituent, and tensile properties. The comparative results show that doping Ce-modified grains with the equiaxed morphology and finer size, increased the mechanical stability of austenite, and enhanced the sphericity of oxide inclusion in the resultant PH13–8Mo. Additionally, the coherency between the newly-formed CeAlO 3 inclusion and matrix was effectively improved after doping Ce, as compared to the original aluminum oxide inclusion without doping Ce. The resultant PH13–8Mo parts doped with Ce yielded an ultimate tensile strength of 1446 ± 20 MPa with a fracture elongation of 16.0% ± 1.5%, for the first time meeting the AMS 5629E H1000 standard for the PH13–8Mo made by additive manufacturing (AM). The enhanced strength results from the strengthening effects of nanoscale precipitation (inclusion) and grain refining. Meanwhile, the ductilizing mechanism can be attributed to the enhanced inclusion sphericity and ameliorative coherency between the inclusion and matrix, and improved misorientation angle of grain boundary owing to the modification by Ce, which efficiently reduced the stress concentration and enhanced cracking resistance during deformation. Therefore, doping rare earth elements presents a promising pathway to synergistically improve the strength and ductility of stainless steels by AM. [Display omitted] [ABSTRACT FROM AUTHOR]

• The detailed precipitation sequence of κ′-carbides and B2 particles in Fe–28Mn–11Al–1C–5Ni (wt%) austenite low-density steel at different isothermal aging temperatures was investigated. • The enrichment of ni element at the phase boundaries among the austenite matrix and κ′-carbides is in favor of the B2 subsequent precipitates. • The homogenously distributed B2 nanoparticles within austenite lead to a significant improvement in the work hardening rate. Precipitation strengthening has been widely adopted in austenitic low-density steel owing to excellent hardened effects. This approach generally employs the coherent κ′-carbides and non-coherent B2 particles. Revealing the precipitation transformation pathway is decisive for further optimizing the microstructures under specific engineering applications. Herein, the detailed precipitation sequence of Fe–28Mn–11Al–1C–5Ni (wt%) austenitic low-density steel as well as its influence on mechanical properties during aging process is systematically investigated. Our results reveal that nano-sized κ′-carbides domains (2 nm) exist in the solution-treated specimen. During aging at 500 °C for 1 h, the cuboidal κ′-carbides (15–20 nm) uniformly disperse in austenite matrix. However, after aging at 700 °C for 15 min, the coarsen κ′-carbides (30–35 nm) inhomogeneously distribute and align preferentially along the 〈1 0 0〉 directions. Further, extending the aging time to 60 min, the needle-type B2 particles replace the κ′-carbides due to the enrichment of Ni elements at the phase boundaries among the austenite and κ′-carbides. After aging at 900 °C, κ′-carbides entirely dissolve into the austenite matrix, and the intragranular B2 particles are the sole precipitates in the austenite matrix and follow the K-S orientation relationship with austenite. The work hardening capability seriously deteriorates due to the shearing of κ′-carbides by gliding dislocations. While the intragranular B2 particles preserve excellent work hardening rate by dislocations bow-out mechanism. The present work is meaningful for guiding the design of new generation dual-nano precipitation austenitic lightweight steel. [Display omitted] [ABSTRACT FROM AUTHOR]

The article discusses the importance of scrap metal recycling in meeting the increasing demand for metals due to global population growth and the transition to renewable energy. The mining industry is facing challenges such as high energy prices and low metal concentrations, leading to a predicted copper shortfall by 2034. To address this, the article suggests using X-ray fluorescence (XRF) and laser-induced breakdown spectroscopy (LIBS) analyzers for fast and accurate elemental analysis in scrap metal sorting. XRF analyzers are effective in analyzing different types of materials, while LIBS analyzers can analyze lighter elements. These analytical tools can enhance metal recovery rates and support a more sustainable future. [Extracted from the article]

[Display omitted] Nitride multilayer coating is prepared on 316L stainless steel (SS) by employing multi-arc ion planting to enhance the corrosion resistance, interfacial electrical conductivity, and hydrophobicity. The electrochemical results show that the coating can effectively inhibit the interface reactions. The i corr of the coated 316L SS was 0.04 μA cm−2, which was significantly lower than that of the substrate (54.7 μA cm−2). The protection efficiency (P i) of the multilayer nitride coating was 99.93%. After 9 hours of PP, the current density of the coated 316L SS stabilized at 0.085 μA cm−2. The typical ICR value of the coated 316L SS slightly increased from 8.6 mΩ cm2 to 12.6 mΩ cm2. The XPS results demonstrated that the significantly increased ICRs (114.7–200.4 mΩ cm2) of the 316L SS substrate were mainly attributed to the increased proportion of Cr oxide, while the oxide content of the coating was still relatively small. The change in surface morphology and current transient events are further discussed. [ABSTRACT FROM AUTHOR]

• The δ-ferrite of I and A + I existed 〈100〉 and 1/2<111> dislocation loops. • Thermal aging accelerated the hardening of irradiated δ-ferrite. • Irradiation did not accelerate the hardening of thermally aged δ-ferrite. • The interaction can promote G-phase precipitation. • The interaction can cause δ-ferrite hardening, which is mainly affected by spinodal decomposition and G-phase. In the harsh service environment of high temperature and intense neutron irradiation in water-cooled nuclear reactors, the austenitic stainless steel weld overlay cladding on the inner surface of the reactor pressure vessel suffers from thermal aging and irradiation damage simultaneously, which can induce microstructural evolution and hardening of the material. Since it is quite difficult to achieve this simultaneous process out of the pile, two kinds of combined experiments, i.e., post-irradiation thermal aging and post-aging irradiation were performed on 308 L stainless steel weld metals in this work. The interactive effect of thermal aging and proton irradiation on microstructural evolution and hardening of δ-ferrite in 308 L weld metal was investigated by combining atom probe tomography, transmission electron microscopy and nanoindentation tests. The results revealed that thermal aging could eliminate the dislocation loops induced by irradiation and affect the phase transition process by accelerating spinodal decomposition and G-phase precipitation, thus enhancing hardening of irradiated δ-ferrite. For the effect of irradiation on the microstructure and hardening of thermally aged δ-ferrite, however, intensive collision cascades can intensify G-phase precipitation and dislocation loop formation but decrease spinodal decomposition, leading to a limited effect on hardening of thermally aged δ-ferrite. Furthermore, the interaction of thermal aging and irradiation can promote G-phase precipitation. Meanwhile, the interaction can cause δ-ferrite hardening, which is mainly influenced by spinodal decomposition, followed by G-phase and dislocation loops, where spinodal decomposition and G-phase cause hardening by inducing strain fields. [Display omitted] [ABSTRACT FROM AUTHOR]

• A gradient nanograined dual-phase structure was produced in 2101 duplex stainless steel. • A superior combination of strength and ductility was achieved by superposition of gradient nanostructure and lamellar dual-phase structure. • Strong hetero-deformation induced strengthening and hardening effect contributes to the superior mechanical properties. Similar to other metallic materials, duplex stainless steel dramatically loses its advantage of high ductility as they are strengthened. Here, we produce a gradient nanograined dual-phase structure in the 2101 duplex stainless steel, thus facilitating a superior strength-ductility synergy: a yield strength of 1009.5 MPa being two times higher than that of the as-received sample, a total elongation of 23.4% and a uniform elongation of 5.9%. This novel structure is produced through a processing route of ultrasonic severe surface rolling and annealing, which realizes a superposition of gradient nanostructure and lamellar dual-phase structure with austenite and ferrite. During the tension deformation of gradient nanograined dual-phase structured duplex stainless steel, a significant accumulation of geometrically necessary dislocations occurs. These dislocations are formed to accommodate the deformation incompatibility caused by the layer-by-layer difference in strength and hardness of individual phase domains, as well as the inherent difference in properties between the austenite and ferrite domains. This results in a stronger hetero-deformation induced strengthening and hardening significantly contributing to superior mechanical properties. Our study provides a new avenue to develop advanced steels with high strength and ductility. [Display omitted] [ABSTRACT FROM AUTHOR]

• Three important mechanisms of inclusion-induced pitting of stainless steels are systematically reviewed. • Contradictory conclusions reported by different pitting mechanism researches are deeply discussed. • Gaps and future research interests on pitting mechanisms of stainless steels are identified. Pitting is a common type of localized corrosion in passive alloys that can cause rapid failure of material or equipment. In the case of stainless steels, non-metallic inclusions have been identified as the most susceptible sites for pitting, and have therefore garnered significant attention. This review critically examines the issue of how inclusions induce pitting, with a particular focus on three mechanisms: spontaneous dissolution of inclusions, active dissolution of Cr-depleted regions, and propagation of microcracks at the inclusion-matrix interface. While researchers have made significant strides in understanding these mechanisms over the past few decades, many gaps and controversies remain. Details such as the initial driving force of inclusion dissolution and factors affecting Cr-depleted regions require further study. Moreover, some old concepts and methods need to be revised to arrive at more credible conclusions. This review aims to delve deeply into these important issues and provide inspiration for future research. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper is a sequel to the previous paper. In the previous research (Ref. 1), a REI-TPA model was established to quantitively relate reversed electrode images (REIs) to welding torch position and attitude (TPA). In this research, the REI-TPA model was validated with bead-on-plate welding experiments on S304 stainless steel plates. The contours of the REI and electrode as well as the weld pool geometry were extracted from the image with a developed, robust algorithm, and the arc length was calculated with welding voltage. The offset distance and deflection angle of the welding torch relative to the correct position and attitude were calculated by inputting the extracted parameters into the REI-TPA model. The computational result was compared to the experimental data. The result showed that the model is correct and the monitoring of the welding torch with the REI-TPA model is available. The REITPA model can be applied to real-time control of TPA, which is a supplement to the application of the weld passive visual image and an extension of multiinformation acquisition and processing methods in the welding process. [ABSTRACT FROM AUTHOR]

• This study investigated the precipitation and segregation of 17-4 precipitation-hardened stainless steel during selective laser melting. • Segregation behavior was calculated with solidification mode of F mode and FA mode due to partitioning coefficient of alloy elements. • Solution treatment after additive manufacturing should be conducted at higher temperatures with longer duration. • The size and area fraction of the precipitates decreased with increasing temperature and duration of the solution treatment. • Hardness increased with the optimized solution treatment owing to the Cu dissolution from the precipitates into the matrix. 17-4 precipitation-hardened (PH) stainless steel (SS) exhibits high strength and good corrosion resistance via Cu-precipitation hardening. Unlike conventional wrought 17-4PH SS, Cu segregation and ε-Cu precipitates are observed in additively manufactured (AM) 17-4PH SS owing to the repeated rapid cooling after heating, which characterizes the AM process. In this study, solution treatment was conducted under various temperatures (1,000, 1,050, 1,100, and 1,200 °C) and durations (1, 2, 4, and 8 h) to minimize the negative effects of Cu segregation and ε-Cu precipitates on precipitation hardening. The mechanical properties and microstructures of each condition for the Cu precipitation behavior were examined. Although the ε-Cu precipitates did not disappear after solution treatment, the average diameter of the ε-Cu precipitates tended to decrease with increasing solution treatment temperature and duration. Therefore, solution treatment at a temperature of 1,200 °C for 8 h was the best, resulting in improved strength compared to the conventional solution treatment at 1,050 °C. Solution treatment on at least 1,100 °C is effective in AM. [ABSTRACT FROM AUTHOR]

• Dissimilar laser welding of CrMnFeCoNi high entropy and 316N austenitic stainless steel was performed. • The ultimate strength of the welded joints is 510 MPa at room temperature and 820 MPa at 77 K, which can reach ∼90 % of the base materials at both room and cryogenic temperatures. • The dominant deformation mechanism was mainly twinning during the plastic deformation which accounting for the higher tensile strength, especially at cryogenic temperature. • The sound welded joints between CrMnFeCoNi high entropy and 316N austenitic stainless steel can be considered for cryogenic applications. The microstructure and mechanical properties of dissimilar laser beam welded joint between CrMnFeCoNi alloy and 316LN stainless steel was investigated. The results showed that the defect-free dissimilar joint was obtained by laser beam welding. The ultimate strength of the welded joints can reach ∼90% of the base materials at both room and cryogenic temperatures. The deformation substructure mainly consisted of planar dislocation, the stacking faults and the dissociation of stacking faults into nanotwins. The volume fraction of the nanotwins was increasing at cryogenic temperature. The hardness fluctuates greatly in welded joint and the lowest hardness was located at fusion zone near the fusion line. The fracture of the welded joint was located at the fusion zone in consistence with the lowest hardness area. It is mainly attributed to the coarse grain and stress concentration at this area. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Photocathodic protection (PCP) is a promising eco-friend method to reduce the corrosion of metals. Considering industrial applicability, it is imperative to adopt cost-effective materials for implementing PCP on corrosion-vulnerable carbon steel (CS). This study examined the potential of photocatalytic TiO 2 -polyvinyl butyral (PVB) materials for PCP of CS and stainless steel (STS) using commercially available P-25 photocatalyst particles. The TiO 2 -PVB-electrophoretic deposition (EPD) film exhibited the improved cathodic protection time of STS owing to PVB addition. When the film was applied to various substrates, it achieved a PCP of −0.6 to −0.7 V SCE due to the photogenerated electrons under UV irradiation. For the CS, the PCP potential was maintained for more than 1.5 hours, even after light irradiation. We have found that PCP was achieved by E corr > E PCP of CS in an acidic environment, while in a neutral and basic environment, the corrosion of CS and photocathodic electronation contributed simultaneously to E corr ≈ E PCP. One findings is that the application of PCP effectively reduces the corrosion rate of CS in a 3.5% NaCl solution, regardless of the pH of the corrosive environment. This highlights the capability of PCP as a viable method for mitigating corrosion on CS. [ABSTRACT FROM AUTHOR]

• The feasibility of the double-sided welding approach to join N40 has been established. • The welds possessed high strength and joint efficiency. • There was no evidence of sensitization in the HAZ of the weldments. • The welds contained lower amount of δ ferrite leading to improved magnetic response. • The FSW approach yielded superior weldments relevant for application in tokamak devices. Nitrogen containing austenitic stainless steels (N-ASS) are widely utilized to fabricate various structural components in tokamak type fusion reactors owing to their suitable mechanical and functional properties. These components are exposed to a range of temperatures (4–500 K) and interact closely with the magnetic fields that are used to control and contain the plasma within the tokamak systems. Nitronic-40 (N40) or XM-11 stainless steel is one such N-ASS used for fabricating structural components in the magnetic and vacuum vessel systems in tokamak devices. Fabrication of most of the larger components in the magnetic and vacuum vessel systems typically involves some type of fusion-based welding process. This study presents a double-sided friction stir welding (FSW) approach as an alternative to fusion welding processes to join 12 mm thick N40 plates to obtain joints with a low fraction of δ ferrite (a detrimental ferromagnetic phase), high joint efficiency, no sensitization and loss of hardness in the heat affected zone, and minimal nitrogen desorption from the weld nugget. The double-sided FSW approach yielded superior weldments when compared to similar joints accomplished by fusion welding for application in tokamak devices. [Display omitted] [ABSTRACT FROM AUTHOR]