Carbon fiber reinforced thermoplastic composites（CFRTP） have superior comprehensive mechanical property，as well as rapid prototyping，weldability and recyclability.The application of CFRTP are gradually increasing in aerospace，vehicle manufacturing and other fields.Ultrasonic welding is recognized as one of the most suitable methods for CFRTP.With the increase of the application of CFRTP in aerospace main load-bearing structures，the discrete solder joints in the form of traditional ultrasonic spot welding are difficult to meet the requirement of the strength of them.Accordingly，foreign scholars have proposed ultrasonic continuous welding technology to realize the seam welding connection of CFRTP structures，which has not been reported in domestic literature.In this paper，the research results of CFRTP ultrasonic continuous welding are reviewed from four aspects：CFRTP ultrasonic continuous welding equipment，joint design，process characteristics and quality inspection.The scientific problems and technical bottlenecks to be solved in CFRTP ultrasonic continuous welding are discussed，so as to provide a reference for the development of CFRTP ultrasonic continuous welding technology of our country.

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.

In the aerospace field， welding serves as the primary joining process for TA3 alloy components，and the microstructure and mechanical properties of its welded joints have a significant impact on the service safety of welded components. This study compares the tensile properties of the base metal and welded specimens and studies the deformation morphology before and after tension using scanning electron microscopy combined with electron backscatter diffraction. The results show that the microstructure of TA3 alloy is equiaxed α grains before welding， and massive， acicular and serrated α grains appear after welding. The yield strength （378 MPa） and tensile strength （458 MPa） of welded specimens are higher than that of base material specimens， but the elongation is lower. The reason is that after the base meterial sample is welded， the welding temperature has the effect of aging treatment on the sample. There exists aging hardening， and the grain size inside the weld area becomes smaller， which will increase the tensile strength. Because the microhardness of the weld zone is obviously higher than that of the base metal zone， the fracture of the welded joint is located in the base meterial zone. The deformation mechanism of the weld zone is stress-induced deformation twin （\mathrm{2}\overline{\mathrm{1}}\overline{\mathrm{1}}2）［\mathrm{2}\overline{\mathrm{1}}\overline{\mathrm{1}}3］ and （\overline{\mathrm{2}}\mathrm{1}12）［\overline{\mathrm{2}}\mathrm{1}13］， with a Schmid factor of 0.038， exhibiting high shear stress and strong coordination of grain deformation. Deformation twins （\overline{\mathrm{2}}\mathrm{11}2）［\mathrm{2}\overline{\mathrm{1}}\overline{\mathrm{1}}3］ also appear in the base material region， but the Schmid factor is 0.078， indicating a relatively high degree of stress concentration.

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 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.

With the widespread application of carbon fiber reinforced polymer （CFRP） in the aerospace field， studying the friction performance at the interface of CFRP and aluminum alloy connections has become increasingly important. This study experimentally investigates the influence of surface microtexture parameters on the friction performance at the aluminum alloy-CFRP interface. The results indicate that both contact pressure and microgroove geometric parameters significantly affect the interface friction performance. As the contact pressure increases from 7.5 MPa to 30 MPa， the sliding friction coefficient significantly decreases， primarily due to the formation and enhancement of a self-lubricating film. Under high contact pressure， the microstructures on the aluminum alloy surface embed into the CFRP plate， creating a plowing effect. The micro-cutting action generates epoxy resin debris that fills the microstructure grooves， forming a stable lubricating film. The groove depth has the most significant impact on friction performance， with a groove depth of 31.8 μm significantly reducing the sliding friction coefficient to 0.197. The synergistic effect of contact pressure and microtexture geometric parameters markedly improves the interface friction performance and connection strength. This study provides theoretical basis and practical guidance for optimizing composite material connection technology.

Lead sulfide quantum dots （PbS QDs） have excellent optoelectronic properties and strong near-infrared light absorption，making them ideal materials for the preparation of near-infrared photodetectors. However，there are still challenges in the process and insufficient performance of the PbS QDs-based optoelectronic detection. In this study，PbS QDs are synthesized by the hot injection method，and the PbS quantum junction infrared detector is prepared by the layer-by-layer method and the solid-state ligand exchange method. The photoelectric performance of the PbS quantum junction infrared detector is improved by the thermal annealing process，and the effect of annealing temperature on the photoelectric performance of the PbS quantum junction is described. The results show that annealing effectively reduces the dark current of the PbS quantum junction infrared detector while increasing the photocurrent，and obtains a stable photoresponse current output. After annealing，the response time of the PbS quantum junction infrared detector is shortened，resulting in a time of 1.9 ms and a delay time of 3.2 ms. The sensitivity of the detector is improved，and the responsivity and detectivity are increased by 1.2 times and 1.3 times，respectively，resulting in a responsivity of 0.78 A·W^-1 and a detectivity of \mathrm{7.8}\times {\mathrm{10}}^{\mathrm{11}}\mathrm{c}\mathrm{m}\bullet \mathrm{H}{\mathrm{z}}^{\mathrm{1}/\mathrm{2}}\bullet {\mathrm{W}}^{-\mathrm{1}}. Annealing effectively improves the crystallinity and the carrier mobility of PbS QDs thin films，while reducing the defect states at the film and interface，resulting in a comprehensive improvement in the optoelectronic performance of PbS quantum junction infrared detectors.

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 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.