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.

The β titanium alloy Ti-1300 is fabricated utilizing laser engineered net shaping （LENS） technology. This study systematically examine the microstructural evolution of the alloy along the deposition direction during the LENS process， and elucidate the intrinsic relationship between its mechanical properties and microstructure. The results indicate that the thermal cycling of each deposited layer in the LENS process has a profound impact on the microstructural evolution. Initially， columnar crystals are formed with a thickness of （15.6±1.2） mm， comprising approximately 20% of the total deposited thickness. Subsequently， these grains transform into equiaxed grains. Within the as-deposited grains， the microstructure undergo a transition from a basket-weave structure to a lamellar structure， and the discontinuous grain boundary α phase changes to a continuous grain boundary α phase along the deposition direction. Notably， the basket-weave microstructure imparts exceptional strength to the alloy. However， the continuous grain boundary α phase tends to promote intergranular fracture， resulting in reduced ductility.

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.

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 mechanical properties of polymer matrix composites often decrease due to hygrothermal environment. The hygrothermal aging tests and the compression tests are carried out before and after aging on the T700/BP9916 composites plate with open-hole， and the open-hole compression（OHC） strength is obtained. The residual stress distribution in the specimen after hygrothermal aging is simulated by ABAQUS software. Based on the hygrothermal expansion behavior and linear relationship between mechanical properties and the moisture absorption， OHC tests before and after hygrothermal aging are simulated. The results show that the moisture absorption of the T700/BP9916 composites have typical Fick diffusion behavior， and the maximum load of the OHC after hygrothermal aging decreases by approximately 5.2%. The internal stress caused by hygrothermal aging is very small and have no impact on the strength. The relative mass increment-time curve of moisture absorption obtained from the FEM simulation is in good agreement with the experimental. The relative error of maximum load of OHC test between the simulated and the experimental value is only 0.88% with non-hygrothermal aging， and the relative error is 6.21% during the hygrothermal environment. The increase in error is due to the fact that only the linear relationship between hygrothermal effect and the linear decline of material properties is considered in the simulation calculation.

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.

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.

8%（mass fraction）Y₂O₃ partially stabilized zirconia （8YSZ） is a currently commonly-used top-coat material for thermal barrier coatings （TBCs） applied to turbine blades in aero-engines. However， its volume change induced by high-temperature phase transitions above 1200 ℃ can easily lead to cracking and failure of TBCs. Sc₂O₃ is employed as an alternative stabilizer to fabricate 8%Sc₂O₃-92%ZrO₂（mole fraction） ceramics （8SSZ） via a solid-state synthesis method. The thermophysical properties of 8SSZ and conventional 8YSZ， including thermal expansion coefficient （CTE）， thermal conductivity， and high-temperature phase/grain stability， are systematically compared. The results show that after heat treatment at 1400 ℃ in a muffle furnace， the CTE of 8SSZ measured by a dilatometer ranges from 8.91×10^-6 K^-1 to 10.7×10^-6 K^-1， which is comparable to that of 8YSZ. Thermal conductivity tests reveal that 8SSZ exhibits a thermal conductivity of 2.59 W/（m·K）， approximately 20% lower than that of 8YSZ. X-ray diffraction （XRD） and scanning electron microscopy （SEM） results demonstrate that 8SSZ maintains phase stability without phase transitions after 500 h at 1400 ℃， outperforming 8YSZ in high-temperature phase stability. However， 8SSZ still exhibits the issue of excessive grain growth.

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 preparation of carbon paper used phenolic resin as matrix carbon， and different heat treatment temperatures （1400-2700 ℃） are used to obtain matrix carbon with different structures. At the same time， the effect of matrix carbon content and structure on carbon paper for proton exchange membrane fuel cell is studied. The results show that the matrix carbon in carbon paper is more prone to graphitization transformation than carbon fiber. As the content of the matrix carbon increases， the d₀₀₂ diffraction peak of the carbon paper becomes sharper. When the heat treatment temperature increases from 2100 ℃ to 2400 ℃， the graphitization of the carbon paper increases by 45.2%， which is the largest increase. With the increase of heat treatment temperature， the carbon papers， with different matrix carbon ratios， show differences in performance trends. When the carbon content of the matrix is 60%（mass fraction， the same below） and 120%， the thickness of the carbon paper gradually decreases with the increase of the graphitization temperature， and the tensile strength of the carbon paper has a slight change； when the carbon content of the matrix is 200% and 350%， with the increase of graphitization temperature， the thickness of carbon paper decreases slightly and then increases， and the tensile strength of carbon paper decreases rapidly. The surface resistivity of carbon paper shows a downward trend with the increase of heat treatment temperature， and its change trend is basically consistent with the change trend of thickness. Therefore， when preparing carbon papers with different properties， it is necessary to consider the synergistic effect of matrix carbon content and structure.