Ultra-thin copper foil, due to its excellent electrical conductivity and mechanical properties, has significant application value in advanced semiconductor packaging and the manufacturing of electrode materials for new energy batteries. Laser processing technology, with its numerous advantages, has become an important technical means for patterning the ultra-thin copper foil. However, the inherent material thermal accumulation effect of laser processing is prone to inducing material damage, severely restricting the processing quality and device performance. This study addresses the issue of damage suppression in ultra-thin copper foil laser processing, innovatively introducing industrial alcohol as an auxiliary processing medium, and deeply exploring the laser cutting mechanism and damage formation mechanism of ultra-thin copper foil in this medium environment. The research results show that the industrial alcohol-assisted medium plays multiple key roles in the laser processing process: first, it enhances the thermal diffusion efficiency and inhibits the expansion of the heat affected zone (HAZ); second, it provides a reducing atmosphere and inhibits the oxidation of molten copper; third, it changes the dynamic characteristics of the molten pool, optimizes the fluidity of the molten metal, and improves the cut seam quality. The synergistic effect of these physical and chemical effects significantly reduces the thermal damage of ultra-thin copper foil, while significantly improving the cutting efficiency and edge quality. By comparing with isopropanol alcohol (IPA), this further verifies the auxiliary advantages of industrial alcohol in the laser processing of ultra-thin copper foil. The research team has successfully developed an efficient and low-damage ultra-thin copper foil laser patterning cutting method based on the industrial alcohol-assisted medium. This method provides a simple and reliable technical solution for the preparation of high-quality ultra-thin copper foil microstructures, and has important theoretical and practical significance for promoting its application in high-end semiconductors, flexible electronics, and high-energy-density batteries.

This study utilized a twisted wire rotating arc cladding method to in situ fabricate a Fe-containing multi-principal element alloy (HPEA) coating derived from NiCrCoTiMo stranded wire on 45 steel (equivalent to AISI 1045 steel). The macroscopic morphology, microstructure, mechanical properties, and electrochemical corrosion behavior of the prepared coatings were examined. The coating exhibited no visible cracks or pores and displayed a dual-phase face-centered cubic (FCC) + body-centered cubic (BCC) structure, with an average grain size of 78 mu m for the FCC phase and 1 mu m for the BCC phase. The microhardness of the coating is approximately 381.3 HV0.1. Compared to 45 steel, the coating's coefficient of friction (COF) decreased from 0.6265 to 0.5125, representing an 18.2% reduction. The calculated wear rate of the coating was 1.47 & times; 10-5 mm3/N & centerdot;m, approximately six times lower than that of 45 steel (8.93 & times; 10-5 mm3/N & centerdot;m). Electrochemical testing revealed that the coating's open-circuit potential (OCP) was -0.405 V vs. the saturated calomel electrode (SCE), with a corrosion potential (Ecorr) of -0.556 V vs. SCE and a corrosion current density (Icorr) of 4.458 & times; 10-6 A/cm2. In comparison, 45 steel exhibited an OCP of -0.582 V vs. SCE, with corrosion parameters of Ecorr = -0.840 V vs. SCE and Icorr = 1.302 & times; 10-5 A/cm2. These results demonstrate the superior corrosion resistance and wear performance of the coating, underscoring its potential for applications in challenging environments that demand enhanced material durability.

Lightweight high-entropy alloy (HEA) coatings are highly desirable for advanced surface protection. This study presents a novel fabrication method for Al-Mg-Ti-Cu-Ni-Cr lightweight HEA coatings via laser cladding combined with in situ alloying, using a specially designed cable-type composite wire consisting of an Al-Mg core sheathed with Cu, Ti, Ni, and Cr-Ni wires. The fabricated coatings exhibit homogeneous composition, high microhardness, and excellent corrosion resistance. Notably, the Al43.5Mg2Ni28Cu15Ti11.5 coating achieves a microhardness of 627 HV0.1 and a corrosion current density of 5.5 & times; 10-6 A/cm2, while the Al43.6Mg2.1Cr2.5Ni25.2Cu15.2Ti11.4 coating shows 523 HV0.1 and a lower current density of 2.8 & times; 10-6 A/cm2. Mechanical analysis reveals that the enhanced hardness stems from synergistic strengthening effects-severe lattice distortion, B2 phase coherent precipitation, and grain refinement. The superior corrosion resistance is primarily attributed to a compact Cr2O3 passive film. This work provides a new strategy for designing and additively manufacturing lightweight HEA coatings.

Sapphire machining poses significant challenges due to its exceptional hardness, brittleness, and wear resistance, resulting in low surface processing quality. Femtosecond laser-induced plasma-assisted ablation (LIPAA) emerges as a promising solution for processing sapphire, yet its surface quality and subsurface damage remain underexplored. This study investigates the influence of crystal orientation, single-pulse energy, scanning speed, number of scans, and target-substrate distance on microgroove surface quality and obtains the order of priority. Experimental results reveal that femtosecond LIPAA processing is unaffected by sapphire anisotropy. Scanning speed predominantly governs microgroove depth-to-width ratio and surface roughness, while single-pulse energy dictates material removal rate. Notably, surface roughness exhibits an inverse correlation with removal rate and depth-to-width ratio. Parametric analysis identifies 90 mu m as the optimal target-substrate distance, yielding maximal depth-to-width ratio, minimal surface thermal ablation marks, and sharp groove edges. Cross-sectional SEM/TEM characterization demonstrates minimal subsurface damage in femtosecond LIPAA: a thin recast layer, limited thermal ablation traces in the amorphous layer, dislocation-free basal slip regions, and undistorted crystalline lattices. These findings confirm that material removal in femtosecond LIPAA is dominated by plasmamechanical bombardment, with thermal ablation playing a secondary role, achieving high-quality microgroove processing in sapphire surface.

Cable wires provide a viable technical pathway for the laser additive manufacturing of high-entropy alloys (HEAs). However, the complex interplay of structural and material parameters of cable wires leads to significant variations in molten pool dynamics, which poses challenges to the fabrication of high-quality HEA coatings. To clarify the effects of these key factors on molten pool behavior, a multi-physics numerical model for the laser cladding of Al50Si6Ti8Cr12Cu12Ni12 cable wires was established in this study. A dedicated physical model for cable wires was developed, and the Level Set Method was employed to track fluid interfaces throughout the cladding process. Based on the proposed model, the temperature distribution, stress fields, and elemental homogeneity within the molten pool were systematically investigated. The results reveal that chromium (Cr) addition induces a viscosity reduction, and a torsional pitch of ≤4 mm is critical for achieving defect-free, compositionally uniform HEA coatings, which provides novel insights for process optimization and alloy design of cable-wire laser cladding.

Objective Microjet water-guided laser technology has found extensive application in micro/nano-manufacturing fields such as microelectronics, aerospace, and biomedical engineering due to its exceptional processing capabilities. However, challenges in laser-water coupling significantly constrain the processing performance of the microjet water-guided laser technology. This coupling process involves the synergistic interaction of two energy fields: a laser beam and a stable liquid jet. The nozzle serves as the critical component for successful coupling, ensuring beam integrity and coaxiality as the laser enters the jet channel. In existing water-guided laser coupling setups, the laser spot is typically divergent and the coupling distance is relatively long, which further complicate the coupling process. This often leads to the jet instability and the direct irradiation of the laser beam onto the inner wall of the nozzle cavity, resulting in nozzle damage. Addressing these issues, this study proposes a method of coaxial assembly of the micro-jet nozzle orifice with its metallic cavity to resolve the coaxial coupling problem between the laser beam and the jet. This approach not only ensures the efficient and complete entry of the laser beam into the jet channel, thereby minimizing laser ablation damage to the inner walls, but also significantly enhances the jet stability, which is crucial for improving the processing accuracy and quality. Methods This study proposes a novel method for achieving high-precision coaxial assembly between the nozzle metallic cavity and its orifice. The approach entails first joining the metallic cavity to an unmachined sapphire orifice material, followed by high-quality drilling at the coaxial position using a precision positioning system. Compared to the conventional " "drill-then-assembly-assembly" process, this method effectively eliminates the errors induced by secondary clamping, while the integrated welding significantly enhances the connection reliability. Specifically, nanosecond laser-induced plasma-assisted micro-welding is first employed to weld the chromium metallic cavity to the unmachined sapphire material. The weld joint morphology, fracture characteristics, and overall quality including interfacial bonding, elemental diffusion, mechanical properties, and hermeticity are systematically characterized and evaluated using scanning electron microscope, energy dispersive spectrometer, Raman spectroscope, shear strength testing, and leak testing. Subsequently, a femtosecond laser system integrated with a precision positioning system is utilized to perform high-precision drilling directly at the predetermined coaxial location on the sapphire material (pre-joined to the metallic cavity and still unmachined). The quality of the resultant sapphire orifice, the coaxial coupling accuracy between the orifice axis and the overall nozzle structure, and the axial pressure resistance of the nozzle assembly are comprehensively analyzed using optical microscopy, ImageJ image analysis software, laser beam profiler analysis, and hydrodynamic pressure testing. Results and Discussions The welding interface between sapphire and chromium metal exhibits a mechanical interlocking structure, with elemental diffusion extending significantly beyond the area directly affected by the laser (Fig. 3). Brittle fracture occurs at the junction between the weld seam and the sapphire (Figs. 4 and 5), while the sapphire/chromium weld joint achieves a shear strength of 262.702 MPa (Fig. 7). The femtosecond laser drilled sapphire orifice demonstrates a diameter of approximately 250 mu m with roundness value of 0.8, featuring intact edges free from cracks or chipping (Fig. 9). The laser spot output from the nozzle distributes uniformly after coupling, with no eccentricity, conforming to the distribution of laser energy (Fig. 10). It confirms the exceptional coaxial alignment between the sapphire orifice and the metallic cavity. Conclusions This study proposes a coaxial assembly method for a microjet water-guided laser nozzle (orifice and cavity): first welding the sapphire to the chromium metal cavity for robust bonding, followed by drilling a high-quality micro-orifice in the sapphire while ensuring its coaxiality with the metallic cavity. Comprehensive analysis of joint morphology, micro-orifice quality, assembly coaxiality, and pressure resistance validates the feasibility. The welded sapphire/chromium joint exhibits good formation without cracks or notches. Distinct elemental diffusion (indicating metallurgical bonding) and mechanical interlocking at the interface confirm reliable bonding. The joint achieves a shear strength of 262.702 MPa with excellent sealing, preventing liquid ingress. The femtosecond laser drilled sapphire orifice, with a diameter of similar to 250 mu m and roughness of similar to 0.8, shows no cracks or chipping, with clean, intact edges. Laser beam profiling of the assembled nozzle output reveals a uniform spot distribution consistent with energy profiles, demonstrating high coaxiality without eccentricity. Pressure testing on axiality confirms structural integrity and tight connection. Combining with the shear strength result, it is indicated that there is a significant load tolerance on nozzle.

Laser-induced plasma-assisted ablation (LIPAA) is considered as a complex and versatile micromanufacturing method to process sapphire, in which the laser and plasma interact on sapphire at the same time, making the processing complicated and prone to low-quality microgroove. This study utilized nanosecond LIPAA to etch microgrooves on sapphire substrate. The relationships between processing parameters (laser scanning speed, laser repetition frequency, number of laser scans, and target-substrate distance) and microgroove characteristics (morphology, width, depth, and roughness) were systematically investigated. While it has been analyzed how the processing parameters affect microgroove formation and variation. Subsequently, a set of processing parameters was selected to fabricate a high-quality microgroove, which was cut perpendicular to the positioning edge to investigate the morphology and damage of subsurface. It is shown that there is a clear ablation morphology in the center part of the microgroove, and numerous dislocations and crystal surface distortions in the transition zone between sapphire and recast layer. These observations demonstrate that sapphire undergoes shear deformation during nanosecond LIPAA process, and the mechanical bombardment by the plasma leads to sapphire lattice slipping and formation of amorphous regions, which can be more easily removed by thermal ablation.

The wire-fed laser cladding has gained significant attention recently due to its advantages as high material utilization rate and a favorable working environment. However, it's limited by the availability of wires, especially for advanced materials like high entropy alloys which are difficult to shape into wires. Cable-stranded wires offer a potential solution to this problem and can expand the application of wire-fed laser cladding. Nevertheless, issues related to tensile failure and loose strands in skein twisting need addressing. Here, we propose an improved skein twisting process, reengineer and fabricate a wire twisting machine for preparing cable-stranded wires. Specifically, Al50Si6Ti8Fe12Cu12Ni12 and Al50Si6Ti8Cr12Cu12Ni12 - two novel lightweight high-aluminum high-entropy alloys - were designed and stranded into Core-Periphery structured wires while the core wire possesses good high-temperature fluidity to ensure uniformity of the cladding layer. The resulting coatings exhibit no cracks with uniform compositions, and exhibit enhanced hardness and corrosion properties.

Rechargeable batteries with metal anodes are recognized as a good option to respond to contentious demand for increasing energy density. However, dendric metal deposition is uncontrollable and causes low Coulomb efficiency and short-circuiting, leading to serious safety issues. Dendric deposition is observed very often in Li and Na metals, while dendrite-free deposition with 100 % Coulomb efficiency is achieved in Mg metal. Additionally, high natural abundance, good machinability, and high stability in ambient conditions of Mg metal make Mg metal anode an ideal metal anode. In 2017, dendric deposition of Mg metal is discovered and possible dendric Mg deposition is also proved by the simulation. These studies reclaim a new research area in developing rechargeable Mg batteries. Recently, the mechanism and suppression of dendric Mg deposition have been studied intensively.In this mini-review, the dendric deposition of Mg metal and its prevention are reviewed. The features of Mg dendrite are studied compared to those of Li and Na dendrites. After that, research on preventing and suppressing Mg dendrite formation is analyzed and summarized. Finally, perspectives and challenges of Mg metal anode are proposed.

Surface textured materials can exhibit enhanced properties due to their unique morphology, large surface area, and modified surface properties. The laser etching process has garnered significant attention for its capability to create textures on sample surfaces, resulting in a substantial improvement of surface properties. In this study, we investigate the application of femtosecond laser etching on solid electrolytes. To achieve this, an axicon lens is employed to transform the conventional Gaussian beam into a Bessel beam, with an extended focal depth that facilitates the laser etching process. A telescope laser system with a Bessel beam having a focal length of 2 mm is constructed based on finite element analysis. Glassy LAGP [Li1.5Al0.5Ge1.5(PO4)3] with a thickness of 2 mm is successfully etched simultaneously on both surfaces using this approach. Utilization of femtosecond laser pulses effectively prevents sample melting during the process. As predicted by finite element analysis, wider ditches are observed on the surface compared to those on the backside due to higher laser intensity at the surface region. By modifying the parameters of the telescope laser system, size and depth control can be achieved for these ditches.

Symmetric Na-ion cells using the NASICON-structured electrodes could simplify the manufacturing process,reduce the cost,facilitate the recycling post-process,and thus attractive in the field of large-scale stationary energy storage.However,the long-term cycling performance of such batteries is usually poor.This investigation reveals the unavoidable side reactions between the NASICON-type Na3V2(PO4)3(NVP)anode and the commercialliquid electrolyte,lead-ing to serious capacity fading in the symmetric NVP//NVP cells.To resolve this issue,an all-solid-state composite electrolyte is used to replace the liquid electrolyte so that to overcome the side reaction and achieve high anode/electrolyte interfacial stability.The ferroelectric engineering could further improve the interfacial ion conduction,effectively reducing the electrode/electrolyte interfacial resistances.The NVP//NVP cell using the ferroelectric-engineered composite electrolyte can achieve a capacity retention of 86.4％after 650 cycles.Furthermore,the electrolyte can also be used to match the Prussian-blue cathode NaxFeyFe(CN)6-z·nH2O(NFFCN).Outstanding long-term cycling stability has been obtained in the all-solid-state NVP//NFFCN cell over 9000 cycles at a current density of 500 mA g-1,with a fading rate as low as 0.005％per cycle.

In all-solid-state batteries, the rigid point contact between the solid electrolyte and electrode results in poor cell interface wettability and generates large interfacial impedance, which hinders the application of solid-state batteries. To enhance ionic conductivity and interfacial wettability of NASICON-structured solid-state electrolyte Li1.5Al0.5Ge1.5(PO4)3 (LAGP), microporous LAGP with a hexagonal surface pattern is prepared using femtosecond laser followed by filling an ionic liquid electrolyte to form a solid-liquid composite electrolyte (HPL&IL). The effect of surface textures on the electrolyte-electrode interface is investigated. Experimental results demonstrate that cycling stability for Li|HPL&IL|Li cells can reach up to 350 hours at a constant current density of 0.05 mA cm-2 at room temperature, and hexagonal surface textures promote uniform interfacial film formation while increasing contact area between electrode and electrolyte, providing more space for charge transfer at the interface.

Portable electronic devices and electric vehicles have become indispensable in daily life and caused an increasing demand for high-performance lithium-ion batteries (LIBs) with high-energy-density. This work compares the intrinsic characteristics and Li + conduction mechanisms of various electrolytes, aiming at emphasizing their suitability for high-energy-density LIBs. Among all electrolytes, polymer-based solid-state electrolytes (SSEs) are the most promising candidates, as they demonstrate the most comprehensive properties. The advantages and disadvantages of commonly used polymer matrix materials of SSEs are discussed, along with typical approaches to address their limitations. As significant issues for high-energy-density and cycle stability, the development related to the cathode/electrolyte interfacial contact and wetting, interfacial electrochemical compatibility, and interfacial Li + conduction in LIBs employing polymer-based SSEs, as well as the anode/electrolyte interfacial chemical stability and lithium dendrite suppression are comprehensively reviewed and analyzed. Finally, perspectives on future research directions for developing high-energy-density LIBs are highlighted building upon the existing literature.

In this study, we designed and developed a combined cable wire made of NbMoTaNiCr multi-principal alloys to meet the demand for high-temperature structural materials. On this basis, the gas tungsten arc welding (GTAW) wire arc additive manufacturing (WAAM) experiments of NbMoTaNiCr multi-principal alloys were conducted, and the microstructure and mechanical properties of the formed layer were analyzed and tested. The result showed that the formed NbMoTaNiCr multi-principal alloys layer at room temperature mainly exhibited a face -centered cubic (FCC) structure with a small amount of mu-phase. The microstructure exhibited the formation of fine and uniform dendrites, with certain dendrite segregation, accompanied by the changed elemental distri-bution. The high-temperature structural phases of the formed NbMoTaNiCr multi-principal alloys layer were BCC, FCC, B2, and mu-phase; the average hardness of the formed layer at room temperature was 911 HV, higher than that of all other systems with a solid-solution structure reported in the literature. At room temperature, the yield strength of the formed layer was 545.5 MPa, and the fracture strain was 9.5%. At 750 and 1100 degrees C, the fracture strains of the formed layer was 6.5 and 6.8%, respectively, while the corresponding yield strength of the formed layer was 597 and 490 MPa, much better than that of the conventional high-temperature alloy Inconel 718 (200 MPa) at 1000 degrees C.

Portable electronic devices and electric vehicles have become indispensable in daily life and caused an increasing demand for high-performance lithium-ion batteries (LIBs) with high-energy-density. This work compares the intrinsic characteristics and Li+ conduction mechanisms of various electrolytes, aiming at emphasizing their suitability for high-energy-density LIBs. Among all electrolytes, polymer-based solid-state electrolytes (SSEs) are the most promising candidates, as they demonstrate the most comprehensive properties. The advantages and disadvantages of commonly used polymer matrix materials of SSEs are discussed, along with typical approaches to address their limitations. As significant issues for high-energy-density and cycle stability, the development related to the cathode/electrolyte interfacial contact and wetting, interfacial electrochemical compatibility, and interfacial Li+ conduction in LIBs employing polymer-based SSEs, as well as the anode/electrolyte interfacial chemical stability and lithium dendrite suppression are comprehensively reviewed and analyzed. Finally, perspectives on future research directions for developing high-energy-density LIBs are highlighted building upon the existing literature.

Laser cladding owns many advantages, such as high instantaneous heating temperature, fast cooling speed, metallurgical bonding between the coating and the substrate, small heat-affected zone and so on. Laser cladding has been used to improve the surface properties of copper and copper alloys for many years. This paper reviews the laser cladding on copper and copper alloys from the following three aspects: cladding materials, coating preparation process and functional coatings. The main problems and corresponding improvement measures for laser cladding on copper and copper alloys are summarized. Finally, the future research direction of laser cladding on copper and copper alloys are proposed.

薄盖玻片由于强度低、透明度好、光学性能影响小的优点在图像、光电、生物等传感器中大量应用,激光诱导等离子体辅助加工技术因能对薄透材质有效间接加工成为了一种新选择.基于激光诱导等离子体辅助加工技术加工薄盖玻片的机理,研究了激光能量密度、扫描速度、加工距离等参数对加工效果的影响规律,为下一代薄透介质的研究应用提供参考.

NASICON-structured solid-state electrolyte, namely Li(1.5)A(10.5)Ge(1.5)(PO4)(3)(LAGP) possesses high ionic conductivity and good compatibility with lithium metal that make it an ideal electrolyte for next generation lithium battery. However, high interfacial impedance and possible dendrite limit its practical applications. To reduce interfacial impedance, herein, surface texturing on the LAGP is conducted using a femtosecond laser, and further wetted by ionic liquids. The femtosecond laser-modified surface can effectively increase wettability and improve the interfacial contacts. Low area specific impedance of 81.452 cm(-2) is obtained and the full battery demonstrates good electrochemical performances.

基于Voronoi图设计了4种不同梯度变化方式的不规则多孔结构,通过光固化成形工艺制备了这4种梯度多孔结构.对这4种梯度多孔结构分别进行了纵向(载荷方向平行于梯度方向)和横向(载荷方向垂直于梯度方向)压缩实验,研究其变形特点和力学性能.结果表明,梯度多孔结构在横向压缩时的变形特点与均匀多孔结构相似,纵向压缩时则表现出逐层坍塌的变形特点.在孔隙率相近的情况下,不同的梯度变化方式能够影响纵向压缩时的力学性能,对横向压缩的力学性能基本没有影响.降低梯度多孔结构的平均孔隙率可以提高结构力学性能.最后通过等应力复合模型和Voigt模型预测了梯度多孔结构纵向和横向压缩的弹性模量,预测结果与实验结果的相对误差基本都在10％以内.

All-solid-state Na battery is one of the most promising batteries because it can solve safety and cost issues of current Li battery simultaneously. In the all-solid-state battery, the interface quality between electrodes and solid-state electrolytes is still one of the critical issues. In this work, surface texturing of Na3Zr2Si2PO12 (NZSP) solid electrolyte is studied. Surface texturing is prepared by the femtosecond laser etching. By the laser etching, periodic surface ditches with 15 μm of width is successfully prepared. Impurity formation is not confirmed after the etching, implying that the laser etching would not affect crystal structure of NZSP. All-solid-state Na battery is constructed by using etched NZSP, NaMnO2 cathode, and Na metal anode. The all-solid-state Na battery works 50 cycles stably. The improvement of performance could be achieved by optimization of the surface texture.