Two types of Mg-1Sr alloy with different size of Mg17Sr2 were prepared through accumulative roll bonding at 350 ℃. As the results shown, DRX occurred during ARB process in both alloys. Due to the difference of Mg17Sr2 particles, the alloy with a size of 0.5 μm of Mg17Sr2 particles shows a finer grain size than that in the alloy with a size of 1.1 μm of Mg17Sr2 particles. Furthermore, the fined size, more amount, and short distance of Mg17Sr2 particles that with a size of 0.5 μm make the alloy show a good DRX trend during ARB process. Mechanical property results reveal that a well performance was achieved in the alloy with a size of 0.5 μm of Mg17Sr2 particles, with an ultimate tensile strength and an elongation is 293.1 ± 5.86 MPa and 7.45 ± 0.16

Achieving high-speed and high-precision motion performance in parallel mechanisms has been a long-standing challenge, particularly in areas like dynamic modeling and identification. In this paper, the dynamic performance of 3-PRR parallel mechanism based on a permanent magnet linear motor is studied for high-precision applications. Firstly, based on the analysis of friction, thrust fluctuations, and branched coupling force which collectively exhibit complex coupling and pose challenges for isolated analysis compensation, the concept of comprehensive resistance fluctuation is introduced to holistically represent these combined disturbances, enabling unified identification and compensation. Secondly, several groups of uniform-motion experiments are designed, and the identification of friction and thrust fluctuations is achieved through spectral analysis. The Newton-Euler dynamics equation is employed to investigate the influence of the branched coupling force on the joint motor of the 3-PRR parallel mechanism. Finally, in the torque control mode, the comprehensive resistance fluctuations at multiple positions are identified using an iterative learning algorithm. Compared to the experimental results mentioned above, the identification of friction force, thrust fluctuations, and comprehensive resistance fluctuation is shown to be reasonable.

Water-soluble inorganic salts in haze significantly accelerate metallic corrosion, posing serious threats to both environmental safety and industrial equipment. Conventional carbon steels, stainless steels, and many engineering alloys often exhibit limited durability in environments coupled with acid and salt. In this study, the corrosion behaviour of the Ni2FeCrMo0.2 high-entropy alloy was systematically investigated in haze-simulating oxalate-containing solutions. A combination of electrochemical measurements, surface morphology observations, and corrosion product analyses was employed to elucidate the effects of oxalic acid concentration and temperature on the corrosion mechanism. The results revealed that Ni2FeCrMo0.2 exhibits markedly superior corrosion resistance compared with 2205 duplex stainless steel. Specifically, increasing the oxalic acid concentration initially decreases the corrosion rate due to complexation-assisted passivation. However, higher concentrations destabilize Cr and Fe based oxides in the passive film, leading to accelerated corrosion. Elevated temperatures further exacerbate corrosion by enhancing ionic mobility and facilitating the penetration of aggressive species. These findings provide mechanistic insights into the passivation behaviour and service performance of multi-principal element alloys in haze-associated corrosive environments, highlighting the potential of high-entropy alloys for applications under complex atmospheric conditions.

Herein, low-Gd-content Mg-Gd-Zr system alloys with novel strength and adequate ductility were prepared by Nd and Y elements alloying combined with hot extrusion. The effects of Nd and Y elements on the microstructure, texture and mechanical properties of as-extruded Mg-6Gd-0.5Zr (VK61), Mg-4Gd-2Nd-0.5Zr (VEK421) and Mg-4Gd-2Y-0.5Zr (VWK421) alloys were investigated. The results showed that the addition of Nd not only refines and homogenizes the alloy structure but also promotes the dynamic precipitation of the secondary-phase particles during the extrusion process; while the addition of Y significantly inhibits the recrystallization behavior of the alloy during extrusion, forming a typical bimodal structure. After extrusion, the VK61 and VEK421 alloys consisted of fine dynamic recrystallization (DRX) grains while the VWK421 alloy consisted of fine DRX grains and coarse deformed grains. The as-extruded VEK421 alloy demonstrated optimal plasticity, characterized by a UTS of 245.4MPa and an EL of 33.6%. The as-extruded VWK421 alloy had the highest volume fraction of the second phase, the lowest recrystallization volume fraction, and the highest texture intensity. It also exhibited optimal tensile strength; ultimate tensile strength (UTS) and elongation (EL) were 261.6MPa and 18.2%, respectively, 66.7% and 106.8% higher than the as-solutionized alloy. The alloy-strengthening mechanisms mainly include fine grain strengthening and dislocation strengthening. Moreover, the presence of DRXed grains with a weak texture plays a significant role in improving the plasticity of the alloy.

To enhance the long-term corrosion resistance of 3D-printed AlSi10Mg alloy, this work designed a two-step micro-arc oxidation (MAO) strategy. Given the difficulty of triggering micro-arc discharge in high-Si Al alloys, an intermediate transition layer was first prepared through one-step MAO in a silicate electrolyte. Subsequently, a two-step MAO treatment was performed in a phosphate electrolyte with the addition of K2ZrF6 to seal the ablation holes formed during the one-step MAO process, achieving a self-sealing effect of the MAO coating. Ultimately, a dense ZrO2/Al2O3 ceramic coating with Si-W-Zr-P gradient distribution was obtained on the AlSi10Mg surface after the two-step MAO. Electrochemical tests reveal that the two-step MAO coating exhibits exceptional corrosion resistance, with a remarkably low corrosion current density (Icorr) of 3.42 x 10-9 A center dot cm-2, along with a protective efficiency (eta p) of up to 99.8 %. Moreover, no obvious macroscopic corrosion signs are observed on the ZrO2/Al2O3 coating after prolonged immersion, and its Icorr remains stable at 9.26 x 10-9 A center dot cm-2, indicating durable protective performance. This study offers a novel and controllable strategy for the design of anti-corrosive coatings on 3D-printed high-Si Al alloys.

We used molecular dynamics simulations to study effect of the water concentration on physical properties and ion transport for the 1-ethyl-3-methylimidazolium chloride/poly(vinylidene fluoride) (EMICl/PVDF) system with 40.03 wt% of EMICl. First of all, we obtain from the pair correlation function that the local spatial structures of EMI+-Cl-, Cl--H2O and EMI+-H2O tend to weaken, while H2O-H2O tends to increase first and then weaken. Secondly, the binding force of Cl--EMI+, Cl--PVDF and EMI+-PVDF gradually weaken, and ions form clusters with water molecules. The diffusion coefficients of water molecules, anions and cations gradually increase, and the transference numbers of anions and cations increase and decrease respectively, indicating that the diffusion coefficient of anions increases faster than that of cations as the water concentration increases. Finally, ideal conductivity and true ionic conductivity gradually increase; compared with anhydrous EMICl/PVDF system, ion-correlated motion is firstly larger, and then smaller.

Stable grasping operations play a pivotal role in enabling robotic dexterity. To achieve a level of proficiency akin to humans, robots must effectively integrate visual and tactile information throughout their grasping tasks. However, relying solely on visual information may not enable robots to achieve dexterous operations. To address this issue, this study explores the application of visual–tactile fusion in robot grasping operations and proposes the YGC model. Specifically, we decompose the grasping operation into three subtasks: target detection, pose generation, and grasping state detection. Firstly, in order to enhance the feature extraction capabilities of the YOLOv5s backbone network, we propose the integration of a multi-scale feature fusion (MSFF) module, which replaces the existing C3 module. In pose generation, we compare various input channels to identify the optimal input method. For grasping state detection, we evaluate the performance of single-modality and multi-modality inputs. Secondly, experimental results show that by replacing the MSFF module, the mean average precision (mAP) value improves by 3.59

A synergistic framework combining deep learning with intelligent optimization algorithms has been proposed to predict the hardness and optimize the composition of Al-Ti-Co-Cr-Fe-Ni system high-entropy alloys (HEAs). This forward prediction model systematically refines and selects candidate features through correlation analysis, solid solution strengthening theory, and the NSGA-III algorithm. A hybrid deep learning model integrating transformer attention mechanisms with a multilayer perceptron has been developed, enabling high-accuracy prediction of HEA hardness (R 2 = 0.9813, RMSE = 10.23577). Furthermore, SHAP analysis was employed to investigate the causal links between features and hardness. An inverse design model based on the Egret Swarm Optimization Algorithm was applied to perform reverse optimization of the forward model, achieving optimal compositional combinations for the specified hardness targets. Validation through laser metal deposition experiments demonstrated that the hardness of the designed alloys matched well with the predicted results, with deviations below 10%. In conclusion, the overall framework for the prediction and design of HEA properties was systematically summarized.

Various constituents of PM 2.5 in haze can accelerate metal corrosion, but traditional carbon steel and stainless steel perform poorly in such complex corrosive environments, and thus developing new corrosion-resistant materials are of great importance for mitigating haze-induced corrosion. The corrosion behavior of Ni2FeCrMo0.2 alloy in haze-simulating aqueous solutions containing various constituents of PM 2.5 in haze is investigated. By the coupling analysis of electrochemical experiments, corrosion morphology, and corrosion product film, the influence of NH4+ concentration on the corrosion mechanism related to multi-principal metal elements is revealed. The results show that the Ni2FeCrMo0.2 alloy exhibits superior corrosion resistance compared with 2205 duplex stainless steel. As the NH4+ concentration increases, the corrosion rate increases initially but then decreases at higher NH4+ concentrations, and the corrosion morphology also confirms this changing trend. The corrosion prompt is primarily due to the lower solution pH caused by the hydrolysis reaction of NH4+. In contrast, the corrosion inhibition at higher NH4+ concentration is attributed to the passive film on the alloy surface, which is composed of Cr, Fe, Mo, Ni, and their oxides, with the presence of Mo elements forming a unique structure that improved the density and stability of the film, thereby inhibiting the growth of corrosion pits. The changing trend of corrosion film resistance and corrosion product film thickness agrees well with this change in corrosion rate. This study provides an insightful understanding of the corrosion behavior of multi-principal alloy materials in haze environments, which is crucial for the corrosion protection design of metal equipment materials.

The AZ80 magnesium alloy was prepared through a series of process including melting, forging, and high-pressure torsion (HPT). The results indicate that the high-pressure torsion process effectively refines the grain size and enhances the mechanical properties of the alloy, particularly at the 1/2 radius of the samples. Furthermore, the dislocation density in the HPT-ed samples is higher than that in the initial sample and decreases with an increasing number of torsion turns. Aging treatment results show that both the degree of recrystallization and the variation in Vickers hardness exhibit stable trends in samples subjected to high torsion turns, especially in the 10-turn sample. This study provides a foundation for controlling the microstructure and mechanical properties of AZ80 magnesium alloy.

The 5xxx series aluminum alloys are widely used in industry due to their excellent weldability and corrosion resistance. However, their relatively low tensile strength (240-400 MPa), compared to 2xxx (410-510 MPa) and 7xxx series alloys (570-690 MPa), restricts their application in high-stress environments. To address the mechanical property limitations of 5052 aluminum alloy, a novel strategy combining copper electroplating, gradient thermal processing, and hot-dip metal mold casting was developed to fabricate copper-interlayered Ti6Al-4V wire-reinforced aluminum matrix composites (Cu-TC4/AMC). Quantitative analysis shows that Cu-TC4/ AMC treated at 860 degrees C for 45 min exhibits a 91.9 % and 22.6 % increase in strength compared to the aluminum matrix and conventional composites, respectively. The copper buffer layer significantly alters interfacial evolution by suppressing Al-Ti interdiffusion through a kinetic barrier effect and redistributing stress due to its ductility. The multiscale interfacial design, achieved through controlled electrodeposition and non-isothermal sintering, addresses the longstanding trade-off between reinforcement efficiency and interfacial embrittlement in titanium-aluminum systems. These findings are supported by X-ray diffraction and EBSD analysis. This work demonstrates an innovative strategy for balancing strength and ductility in aluminum matrix composites, offering new insights into interfacial design for high-performance structural materials.

In this study, laser shock peening (LSP) was used to modify the microstructure and mechanical properties of 2060-T8 aluminum–lithium alloy. The results demonstrated that LSP induces a gradient hardened layer and high amplitude compressive residual stress into the material. Due to the plastic deformation introduced by LSP, more stable and higher density geometrically necessary dislocations were developed around the grain boundaries, which changed the microstress distribution of the hardened layer and produced a more stable strengthening effect of hetero-deformation. The influence of LSP treatment parameters, processing sequence for the LSP treatment, and drilling on the fatigue properties of the alloy was also studied. The fatigue life of samples with holes drilled either before or after LSP were both improved. However, the fatigue life of the samples that were drilled after treatment was much longer than that for samples drilled prior to treatment. For the untreated sample, the crack initiated at the edge of the hole. However, after LSP with different sequences, the fatigue crack initiation location shifted to the most vulnerable position of the sample, such as the central region along the thickness direction or the transition area between LSP-treated and untreated regions.

In order to improve the microstructure and corrosion resistance of entropy alloy in the FeCrNi system, laser melting deposition technology was used as a preparation method to study the effects of different contents of Al and Ti on the microstructure and corrosion resistance of entropy alloy in FeCrNi(AlTi)x (x = 0.17, 0.2, and 0.24). The results show that the addition of Al and Ti elements can change the phase structure of the alloy from a single FCC phase structure to an FCC + BCC biphase structure. The BCC phase volume fraction of FeCrNi(AlTi)0.2 is the highest among the three alloys, reaching 37.5%. With the addition of Al and Ti content, the grain of the alloy will be refined to a certain extent. In addition, the dual-phase structure will also improve the corrosion resistance of the alloy. In 3.5 wt.% NaCl solution, the increase of Al and Ti content can effectively improve the protection of the passivation film on the surface of the entropy alloy in FeCrNi(AlTi)x, effectively inhibit the large-scale corrosion phenomenon on the alloy surface, and thus improve the corrosion resistance of the alloy. In a certain range, increasing the content of Al and Ti elements in the FeCrNi(AlTi)x system can improve the corrosion resistance of the alloy.

In this work, CoCrMoNb(TiC)(x) high entropy alloy coatings with various TiC contents were fabricated by using the laser cladding technology. The effect of TiC content on the microstructure and mechanical properties of the coatings was investigated. The tribological properties of the CoCrMoNb(TiC)7.5% coatings were investigated in the temperature range from room temperature (RT) to 800 degrees C. The results showed that the CoCrMoNb(TiC)x coatings were mainly composed of BCC, FCC phases, and a small amount of Laves phases. The addition of TiC introduced new compounds such as Cr3C2 and NbC into the coatings. As the TiC content increased, the skeletallike structure progressively bonded and fused in the coating, resulted in a denser structure. The CoCrMoNb(TiC) 7.5 % coating exhibited the largest microhardness of 938HV0.3 and best wear resistance (1.6 x 10(-5) mm(3)/Nm) at RT, which was mainly attributed to the synergistic effect of solid solution strengthening, fine grain strengthening, and dispersion strengthening by hard phases such as TiC, Cr3C2 and NbC. The CoCrMoNb(TiC)7.5% coating demonstrated the best tribological property at 800 degrees C, primarily due to the formation of a dense enamel layer composed of Cr2O3, Co3O4, Nb2O5, and other oxides on the worn surface, which effectively reduced the friction and enhanced the anti-wear resistant of the coating.

As ecological issues intensify, the use of conventional corrosion inhibitors fails to satisfy developmental demands, prompting researchers to focus on economically viable and environmentally benign alternatives. In this work, an environmentally sustainable biomass carbon quantum dots (BCQDs) corrosion inhibitor was synthesized through a hydrothermal method, utilizing passion fruit peel (PFP) as the primary raw material. Electrochemical analysis, weight loss experiments, and other surface characterization techniques were conducted to investigate the corrosion inhibition properties of BCQDs for Q235 steel in 1 M HCl. The dates of electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) curves, and weight loss experiments indicate that BCQDs can provide an excellent corrosion inhibition effect under acidic conditions. Specifically, the addition of 80 mg/L BCQDs may provide a corrosion inhibition effectiveness of 90%. The linear fitting of the Langmuir adsorption model confirmed the efficacy of BCQDs as mixed-type corrosion inhibitors on steel surfaces. The analysis of the surface morphology of Q235 steel using scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle measurement (CAM) revealed that BCQDs create a protective film through adsorption, which helps to reduce metal corrosion. Additionally, findings from X-ray photoelectron spectroscopy (XPS), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, and time-of-flight-secondary ion mass spectrometry (TOF-SIMS) further confirm the interaction between the functional groups on the BCQD molecules and the steel surface. This study provides a theoretical foundation for the development of biomass environmentally friendly corrosion inhibitors and the metal pickling industry.

Overcoming the strength-plasticity trade-off by regulating grain size and precipitation behavior remains a central challenge in magnesium (Mg) alloy development. This study investigates the synergistic improvement of strength and ductility in Mg alloys by partially substituting Gd with Nd and Y to tailor precipitation behavior and grain structure. Using extruded VK61 as the base alloy, the addition of Nd (VEK421) transformed Mg5 Gd precipitates into Mg5 (Gd, Nd), preserving the original phase structure. Further alloying with both Nd and Y (VWEK4111) refined the precipitates to nanoscale Mg24 (Gd, Y, Nd) 5. Compared to VK61, precipitate sizes in VEK421 and VWEK4111 were reduced by 25.8 % and 51.4 % and precipitate area fractions were increased by 12.6 % and 24.6 %, while grain sizes decreased by 34.4 % and 56.3 %, respectively. The alloying elements also influenced slip behavior, with Nd and Y suppressing basal slip and promoting non-basal slip activity, thereby improving deformation uniformity. Tensile tests showed that VEK421 achieved a yield strength (YS) of 184.9 MPa and elongation (EL) of 33.6 %, representing increases of 15.6 % and 40.6 % over VK61. VWEK4111 further improved YS to 220.6 MPa (up 37.8 %) and EL to 26.9 % (up 15.5 %). These enhancements are attributed to grain refinement and activation of pyramidal slip. This work demonstrates an effective alloy design strategy for cost-efficient, high-performance Mg alloys via microstructure and precipitation engineering.

Lean duplex stainless steel 2101 (LDX 2101) is a promising material to replace 304 austenitic stainless steel in nuclear power plant in the future and it has been widely studied for its good economy, mechanical properties and corrosion resistance. Aiming at the underwater maintenance of nuclear power, the microstructure and texture evolution of laser wire direct energy deposition in underwater environment were studied by means of optical microscope and electron backscatter diffraction. The results show that the rapid cooling effect of underwater environment on the molten pool inhibits the transformation from ferrite to austenite. Since ferrites have the lowest surface energy, most of them were precipitated along the dense-packed (111)α and (110)α planes. The deposition structure shows typical cube texture and Goss texture. Although the texture of austenite is not as strong as that of ferrite passing through the deposition layer, the results show that the austenite phase was formed with a close Kurdjumov-Sachsorientation orientation relationship with respect to the ferrite phase. It is also found that the cyclic reheating effect of laser wire direct energy deposition not only changes the microstructure and texture, but also affects the grain size and the proportion of special grain boundaries. Improving the content and distribution uniformity of Σ3 grain boundary in the deposition structure is beneficial to improve the corrosion resistance.

Solar panels in low earth orbit (LEO) can suffer from damage caused by atomic oxygen (AO) exposure and thermal shock, which may shorten the service life of their interconnectors and joints. Ag-plated Kovar foil has emerged as a promising material for interconnecting solar cell arrays. This study uses parallel gap resistance welding (PGRW) to conduct ultrafast Ag-plated Kovar foil and solar cell bonding in just 190 ms. The bonding strength depends on the current densities, with a diffused interface observed at a density of 475A/mm2. The EBSD results show that grains of Ag layer and Au layer grow at the central bonding interface, whereas grains of Ag layer and Au layer form a weakened bonded line at the edge bonding interface. The thermal reliability of joints with Ag-plated Kovar foil is better than traditional Ag foil, with no decline in tensile-shear force observed even after multiple thermal cycles. Although the Ag layer of Kovar foil oxidizes as AgO and Ag2O in an AO environment, the joining interface remains unaffected. This investigation into PGRW joints of Ag-plated Kovar foil is critical for enhancing the high reliability of solar arrays in harsh temperatures and AO space environments.

To clarify the evolution of lamellar phases in the initial microstructure of the Mg-9Gd-0.8Al alloy during the extrusion process and the effect of lamellar phases on the dynamic recrystallization of the extruded Mg alloy, the solid solution treated Mg-9Gd-0.8Al (SS10) alloy, was extruded at different temperatures (380, 400, and 450 °C). With the extrusion temperature increasing, the average size of dynamically recrystallized (DRXed) grains and the second phases decreases firstly and then increases. However, the volume fraction of DRXed grains shows an opposite trend, while the amount of the second phases consistently decreases. The as-extruded SS10 alloy demonstrates superior mechanical properties when extruded at 400 °C, with a yield strength (YS) of 240 MPa, ultimate tensile strength (UTS) of 298 MPa, and elongation (EL) of 19.3%. The alloy achieves enhanced strength through grain boundary strengthening, dislocation strengthening, and Orowan strengthening. Moreover, the presence of DRXed grains with a weak texture plays a significant role in the improvement of the ductility of the alloy.

Super duplex stainless steel UNS S32750 is widely used in marine industries, pulp and paper industries, and the offshore oil and gas industry. Welding manufacturing is one of the main manufacturing processes to make material into products in the above fields. It is of great importance to obtain high-quality welded UNS S32750 joints. The austenite content and ferrite content in UNS S32750 play an important role in determining UNS S32750 properties such as mechanical properties and corrosion resistance. However, the phase proportion between the ferrite phase and austenite phase in the welded joint will be changed during welding. Lots of research has been done on how to weld UNS S32750 and how to obtain welded joints with good quality. In this work, the recent studies on welding UNS S32750 are categorized based on the welding process. The welding process for UNS S32750 will be classified as gas tungsten arc welding, submerged arc welding, plasma arc welding, laser beam welding, electron beam welding, friction stir welding, and laser-MIG hybrid welding, and each will be reviewed in turn. The microstructure and properties of the joints welded using different welding processes will also be discussed. The critical challenge of balancing the two phases of austenite and ferrite in UNS S32750 welded joints will be discussed. This review about the welding process for UNS S32750 will provide people in the welding field with some advice on welding UNS S32750 super duplex stainless steel.