Key components of high-end equipment are often exposed to harsh wear， corrosion or high-temperature environments， thus requiring higher wear resistance， corrosion resistance and high-temperature resistance. As one of the most promising surface engineering technologies at present， thermal spraying technology can be widely applied to many key components of high-end equipment to achieve the purpose of improving their surface performance. Nano thermal spraying technology is an important means to effectively combine nanomaterials and thermal spraying technology to achieve material surface modification. It is also an effective solution to extend the service life of aircraft， ships， and other high-end defense equipment in extreme environments. Nanostructured powder re-granulation technologies enable precise control over the phase composition and microstructure of thermal spray feedstocks at the nano-micro scale. This facilitates the fabrication of nanostructured coatings with tailored properties to meet diverse surface performance requirements for critical components in advanced equipment. This paper briefly summarizes the development status of nanostructured coatings with different functional orientations prepared by thermal spraying at home and abroad in the recent decade， mainly including nanostructured wear-resistant and corrosion-resistant ceramic coatings， nanostructured thermal barrier coatings， nanomodified MCrAlX alloy coatings， nanomodified WC-Co based cermet coatings and nanostructured environmental barrier coatings， etc. The results show that nanostructured and nanomodified thermal spray coatings have a very good potential to be applied on key components of high-end equipments， which can be used to meet the various surface properties required by key component of high-end equipment. key components of high-end equipment have very broad application prospects. To realize the wide application of nanostructured coatings， further research work needs to be carried out in the future in the areas of practical engineering application research， marine environmental service， marine biofouling， advanced powder preparation technology research， and high-performance powder industrialization.

Spectral computed tomography （spectral CT） is an emerging detection technology that acquires more comprehensive tissue composition information by measuring an object’s absorption of X-rays of different energies. It plays a pivotal role in various fields such as medical diagnosis， non-destructive testing， material analysis， and security monitoring. Material decomposition algorithms are the core of spectral CT technology， aiming to decompose the composition information of different tissues from multi-energy data. These algorithms are crucial for enhancing the quality and accuracy of decomposed images. This paper reviews the data acquisition methods and mathematical models for material decomposition in spectral CT. It focuses on discussing the research progress of spectral CT material decomposition algorithms in four aspects： projection domain， image domain， direct iteration， and deep learning-based methods. It conducts an in-depth comparative analysis of the theoretical advantages， technical limitations， and current application status of various algorithms. The paper points out that the future research trends in this field include hybrid decomposition optimization in the projection domain， fusion prior constraints and multi-model data in the image domain， convergence stability improvements in direct iteration， and transferability and high generalization in deep learning.

The Fe-Ga alloy， a novel magnetostrictive material， distinguishes itself with a low driving magnetic field and remarkable magnetostrictive performance. As an alloy， it has garnered significant attention from researchers in solid-state physics and materials science due to its cost-effectiveness， superior mechanical properties， and high stability. These advantages make it particularly appealing for applications in micro-displacement devices， vibrators， and sensor technologies. The magnetostrictive characteristics of Fe-Ga alloys are influenced by various factors， including material texture orientation， magnetic domain distribution， alloying element additions， and， most importantly， the alloy’s phase structure. This paper provides an in-depth exploration of the phase structure of Fe-Ga alloy and comprehensively summarizes the impacts of various preparation methods on enhancing the preferred grain orientation 〈100〉. It further examines the effects of specific external magnetic fields and prestresses on altering the distribution of magnetic domains， as well as the influence of incorporating rare earth elements on improving magnetostrictive performance. Additionally， the article introduces recent research advancements regarding the influence of heat treatment on phase structure transformation and nanoprecipitate phase precipitation on the magnetostrictive properties of Fe-Ga alloys，contributing to advancing the understanding， promotion， and application of Fe-Ga alloy in the field of structure-function integrated precision device manufacturing.

Microstructures and mechanical properties of GH4169 alloy cylinder and its weld joints in a supercritical water reactor are studied after operating 2000 h. The results show that the GH4169 alloy cylinder exhibits good corrosion resistance under conditions of high temperature， high pressure， and sucrose mixed solution； the thickness loss rate of the cylinder is 0.005-0.255 μm/h； the corrosion products primarily consist of oxides and phosphates. However， the welded joints connecting the cylinder and other components represent a vulnerable point that significantly impacts the remaining lifespan of the reactor. The calculated crack propagation rate of the GH4169 alloy cylinder is 5.25 μm/h， indicating that it would only take 762 h for the crack to penetrate through the wall of the connector. Additionally， severe fracture occurs （the circumferential length of the crack is approximately 1/4 of the circumference） at the weld joint between cylinder and stainless-steel， resulting from the synergistic effects of galvanic corrosion， crevice corrosion， and concentrated stress. Despite these challenges， the strength loss of the cylinder is relatively small， which means that the cylinder maintains satisfactory mechanical properties.

To address the evolving demands for the clean and efficient utilization of coal， efforts have been devoted to the research and development of C700R-1 nickel-based alloy rotor forgings for advanced ultra-supercritical steam turbine rotors. Concurrently， tests are conducted on the conventional mechanical properties and creep rupture properties of the trial-manufactured rotor forgings. The results show that the use of the closed upsetting+extrusion method enables the high-homogeneity forging of Φ850 mm forgings. The as-forged grain size of the developed large-section forgings ranges from grade 4 to grade 7， and the grain size after heat treatment is approximately grade 3. Due to the rapid cooling rate of the edge parts after solid solution， a large number of uniform and fine γ' phases precipitate in the subsequent aging process. Therefore， the tensile properties of edge position are slightly better than those of the heart and 1/2R position. The variation of tensile properties in different directions of edge position is small. The room temperature tensile strength can reach 950 MPa， the yield strength can reach 600 MPa， and the V-notch absorbed energy at room temperature is beyond 70 J at different positions after heat treatment. The tensile strength can reach 750 MPa， yield strength can reach 500 MPa at 700 ℃. The plasticity is higher than 25% at room temperature and 700 ℃. The creep life exceeds 7000 h in the condition of 700 ℃/300 MPa. Through the deformation mode of closed upsetting+extrusion and reasonable heat treatment process， the homogenization manufacturing of nickel base alloy forgings with a section grade of Φ850 mm， which provides key data for the subsequent manufacturing of full-size nickel base alloy rotor forgings.

Welding of cryogenic 9Ni steel is performed using NiCrMo alloy systems with different Nb and C contents. The microstructure and mechanical properties of the welded joints are investigated， and the fracture toughness of the joints under ultra-cryogenic conditions is analyzed by crack tip opening displacement （CTOD） tests. The results show that the welded joint exhibits distinct zoning characteristics. The nickel-based weld metal primarily consists of an austenitic columnar crystal matrix and secondary phases. The secondary phases include fine nanoscale banded precipitates and Nb-rich solidification phases formed in the final stage of weld pool solidification. The precipitates are mainly composed of metal carbides （MC） and Laves phases. With the increase of Nb and C content， the number and average particle size of secondary phases in the nickel-based alloy increase， leading to an improved tensile strength of the joint， but reduced cryogenic impact toughness and fracture toughness. The load-notch opening displacement （F-V） curves show that the characteristic load F_m of the joint first increases and then decreases with the addition of Nb and C， while the corresponding characteristic plastic displacement value V_p decreases monotonically with the increase of secondary phases. The fracture surface of the CTOD specimens shows the same zoning characteristics. As the Nb and C content increases， the width of the stable crack propagation region on the fracture surface gradually decreases， indicating a deterioration in the fracture toughness of the weld.

The desirable combination of ultra-high strength and good toughness enables the secondary hardening ultra-high strength steel widely used in aerospace and energy equipment. The influence mechanism of quenching temperatures on the microstructure and mechanical properties of Co-conserving 2.2 GPa ultra-high strength steel is investigated by using scanning electron microscope（SEM），transmission electron microscope（TEM），tensile and impact testing machine. The results show that when the quenching temperature is 950 ℃， there are many undissolved M₆C carbides and unrefined grains in the matrix， resulting in lower strength （tensile strength：2072 MPa， yield strength：1873 MPa）. As the quenching temperature increases， recrystallization promotes the refinement of the matrix grains， and the number of M₆C carbides gradually decreases； such partial dissolution favors the precipitation of hardening phases， resulting in a recovery of strength； when the quenching temperature is 1030 ℃， the experimental steel has excellent combination of strength-plasticity-toughness： the tensile strength is 2251 MPa， the yield strength is 1901 MPa， the elongation is 9%，and the V-notch impact absorbed energy is 9 J. By further increasing the quenching temperature， the rapid growth of austenite grains leads to severe plasticity attenuation， with elongation of only 4.5% at 1120 ℃. Between 1030-1090 ℃， there is a competitive relationship between the dissolution of M₆C carbides and grain growth. Although higher temperature quenching promotes dissolution， the severe coarsening of grains offsets the former’s beneficial effect on toughness to enable a stable performance of strength and toughness.

To develop high-temperature wear resistant steel with high tempering stability that can be used in high temperature environments， the bond energy between different alloying elements and C element is calculated by solid and molecular empirical electron theory， and a series of TiC particle-reinforced high-temperature wear-resistant steel components are designed. The precipitation temperature of TiC particles is calculated by Thermo-Calc software and the tempering stability of the steel plate after the best heat treatment is tested at different temperatures and time. The results show that the bond energy formed by Cr， Mo， and W with C is significantly higher than that of Fe—C. Therefore， the activation energy of C atom diffusion in martensite increases， which hinders the diffusion of C atom in martensite and improves the tempering resistance of martensite. Therefore， Cr， Mo， and W are determined as the main addition elements to improve the thermal stability of TiC-reinforced martensitic wear-resistant steel. TiC particles precipitate in the temperature range of 1400-1500 ℃， and the particle morphology shows that the particles distribute like grain boundaries. After thermomechanical processing， micron TiC particles can uniformly distribute on the matrix. The experimental results of tempering stability show that the addition of Cr and W elements greatly improves the tempering stability.

The thinning is a trend in the development of high-end electrical steel. Although its iron loss can be further reduced， the larger cold rolling reduction and the surface effect can influence the microstructure and texture of the final product， thereby affecting the magnetic properties. The two-stage cold rolling method can optimize the texture and increase the proportion of ｛100｝ and Goss textures. The influence of processing parameters on the microstructure， texture， and magnetic properties of a 0.10 mm thick ultra-thin non-oriented electrical steel is investigated by the two-stage cold rolling method， with a focus on the role of surface effects during prolonged holding. The results show that cube and Goss textures coexist in the final sheets produced by the two-stage cold rolling method. Furthermore， when the combined reduction from the two stages falls within the range of approximately 75% to 81%， the resulting texture and magnetic properties are superior to those of samples with reduction combinations of 90%/50% and 50%/90%. Within the temperature range of 840-920 ℃， the influence of time on grain growth is greater than that of temperature， and grain growth is affected by the surface effect in all cases. During isothermal annealing at 920 ℃， the 0.1 mm thick sample exhibits a more significant surface effect compared to the 0.27 mm thick sample， meaning grain growth is significantly hindered； the average grain size after the annealing for 60 min could not exceed the sheet thickness of 100 μm. In contrast， the average grain size of the 0.27 mm thick sheet grows to 175 μm.

With the improvement in aeroengine performance，critical components （such as centrifugal impellers） operate under high-temperature，high-stress，and complex load conditions. Geometric discontinuities （such as ventilation holes and fillet radii） have become weak points for fatigue failure. This study focused on TA19 material，preparing smooth and U-shaped notch specimens for low-cycle fatigue tests under high-temperature conditions. Fatigue life data have fitted using the Weibull distribution，and an improved iterative fatigue life model is proposed to address the limitations of traditional models in regions with stress concentration. The model incorporates the stress concentration factor （K_t） and first-order reliability theory for correction. The results indicate that due to stress concentration effects，U-shaped notch specimens exhibit more concentrated fatigue life distributions，whereas smooth specimens show greater variability. The Kolmogorov-Smirnov test verifies that the data conforms to the Weibull distribution characteristics. The revised model significantly improves the prediction accuracy，with most of the predicted data falling within±1.5 times the scatter band. Additionally，P-S-N curves for different failure probabilities are constructed，providing a valuable reference for the reliable fatigue life prediction of complex structures.