The influence of rare earth Ce on theα-Al grain size and eutectic Si morphology in the solidification microstructure,phase composition,and hardness of ZL114A aluminum alloy was investigated through a sand casting process simulation experiment.The results indicate that theα-Al grain size in the solidification microstructure of ZL114A aluminum alloy initially decreases and subsequently increases with the increase of the addition amount of rare earth Ce,while the Vickers hardness of the alloy exhibits an opposite trend of first increasing and then decreasing.The optimum mass fraction of rare earth Ce is 0.3%.Under this condition,the average grain sizes at the core and edge of the ingot decrease from the original 157μm and 143.2μm to 125.7μm and 122.6μm,respectively,corresponding to decreases of 19.9%and 14.4%.The morphology of eutectic Si transforms from the original lath shape to fine rod shape.Additionally,the addition of rare earth Ce promotes the preferred orientation growth of Al and Si atoms along the〈100〉and〈110〉directions.The Vickers hardness values at the core and edge of the ingot increase from the original 62.9 HV and 68.3 HV to 70.3 HV and 75.3 HV,respectively,corresponding to enhancements of 11.8%and 10.2%.

Copper-based composite oxide catalysts were prepared by impregnation method usingγ-Al₂O₃ spheres as carrier and Cu-Ce,Cu-Mn,Cu-Zr or Cu-Co as active components.The influence of different components,doping ratio and reaction temperature on the catalytic performance of copper-based composite oxides for CO oxidation was studied.The surface properties,reducibility,surface morphology and phase composition of the catalysts were analyzed by BET,CO-TPR,SEM and XRD.The results show that under the optimal doping ratio,the order of catalytic activity of copper-based composite oxides with different active components is as follows:Cu-Ce composite oxide>Cu-Mn composite oxide>Cu-Zr composite oxide>Cu-Co composite oxide.Among them,the Cu-Ce composite oxide exhibits the best performance,and the optimal doping ratio is n(Cu)∶n(Ce)=1∶0.1.This catalyst achieves a CO conversion rate of over 80%at 150~200℃and maintains a CO conversion rate of over 90%above 200℃.Characterization results indicate that the excellent catalytic activity of the Cu-Ce composite oxide is attributed to the uniform dispersion of active components,large specific surface area,good pore structure and strong redox ability.

To investigate the effects of ultrasonic vibration on the grain size and preferred orientation of hot-deformed Nd-Fe-B magnet and the mechanisms,ultrasonic vibration was applied during the hot deformation process of Nd-Fe-B.The grain size distribution of the magnet was analyzed through SEM images and Image Pro Plus software.The grain orientation degree of the magnet was analyzed by XRD patterns and SEM grain morphology.Additionally,the strain activation energy and magnetic properties of the magnet were analyzed.The results indicate that ultrasonic vibration has a grain refinement effect on the hot-deformed Nd-Fe-B,and its average grain size in the refined region decreases by about 50%compared with the conventionally hot-deformed magnet.Moreover,increasing the ultrasonic power density can significantly enhance the grain refinement effect.Ultrasonic vibration promotes the rotation of the grains of the main magnetic phase,and more grains align their c-axis with the pressure direction,improving the overall preferred orientation.In addition,ultrasonic vibration promotes the uniform distribution of grain orientation in the radial direction of the magnet,reducing the difference in the remanence of the hot-deformed magnet along the radial direction.

The room temperature mechanical properties and microstructure of as-extruded and extruded plus high-temperature(1150℃,1200℃,1250℃,and 1300℃)quenched low-density niobium alloy(Nb-35Ti-5Al-5V-1Zr-0.08C)rods were studied through room temperature tensile experiments and metallographic observations.The mechanism of the significant improvement in room temperature plasticity of the quenched alloy was also explored.The results show that compared with the as-extruded alloy,the room temperature elongation at break and reduction of area of the four high-temperature quenched alloys were significantly improved.Among them,the alloy quenched at 1300℃exhibits the highest room temperature elongation at break(18.5%)and the highest reduction of area(48%).Due to coarse matrix grains and large and segregated TiC second-phase particles,the as-extruded niobium alloy rods undergo brittle fracture during room temperature tensile testing.High-temperature quenching promotes the dissolution of TiC se-cond-phase particles back into the matrix,and the increase in quenching temperature further enhances the refinement and spheroidization of TiC second-phase particles.High-temperature quenching also induces the transformation of some coarse grains into subgrain structures,resulting in a grain refinement effect and ultimately greatly improving the room temperature plasticity of the low-density niobium alloy extruded rods.

Ti-0.3Mo-0.8Ni titanium alloy was selected as the test material and subjected to solid solution treatment at different temperatures.The effects of solution temperature on the microstructure and tensile properties of Ti-0.3Mo-0.8Ni titanium alloy were studied by optical microscope(OM),scanning electron microscope(SEM),X-ray diffractometer(XRD)and tensile property test.The results show that the original microstructure of the alloy is an equiaxed microstructure formed by forging in the two-phase region,which is composed of a large number of primaryαphase(α_p)and a small amount ofβ-transformed microstructure(β_T).With the increase of solution temperature,theα_p phase in the microstructure of the solution-treated alloy gradually becomes smaller,and finally completely dissolves and disappears,while the content of the precipitatedα′phase increases and the size gradually increases.And the strength of the alloy increases,while the plasticity decreases.The fracture micro-morphology of the alloy changes from dimple to crystalline morphology,tear ridges gradually appear,and the fracture characteristic changes from ductile fracture to brittle fracture.

Ti(C,N)-based cermets have been considered as ideal materials to replace traditional WC-based cermets due to their abundant resources,low cost and excellent physical and chemical properties.However,their low fracture strength and toughness limit their application in high-speed cutting.This paper reviews the reaction mechanism and the influence of key process parameters of the carbon thermal reduction nitridation method for preparing Ti(C,N)solid solution powder,analyzes the shortcomings of the current Ti(C,N)powder preparation methods,and prospects the future research directions.The reaction process of preparing Ti(C,N)powder by carbothermal reduction nitridation method is divided into three stages:TiO₂ undergoes solid-solid reaction with C atoms to generate Ti₃O₅ intermediate phase,Ti₃O₅ intermediate phase undergoes gas-solid reaction with N₂ and CO to generate Ti(C_x,N_y,O_z),and the C,N and O atoms in Ti(C_x,N_y,O_z)undergo displacement reaction to obtain Ti(C,N)powder.Increasing the reaction temperature and prolonging the reaction time are beneficial for increasing the C content of Ti(C,N)powder,but increase its grain size,while carbon source with a small particle size and optimized nitrogen flow rate can improve the purity and performance of Ti(C,N)powder.Although the carbothermal reduction nitridation method is considered as the dominant technology for preparing Ti(C,N)due to its low cost and easy industrialization,it still faces challenges such as low product purity and coarse grain size.Future research needs to focus on developing efficient and economical preparation processes,accurately regulating the particle size of Ti(C,N)solid solution powder and reducing agglomeration,so as to promote the industrial application of Ti(C,N)-based cermets.

Fe₃O₄ nanoparticles were prepared by triethanolamine hydrothermal method,nano Au-Ag alloy sol was synthesized by sodium citrate co-reduction method,and Fe₃O₄ nanoparticles were modified by surface amination.Subsequently,Au-Ag nanoparticles were loaded onto Fe₃O₄ to synthesize Fe₃O₄-Au-Ag magnetic composite nanomaterials,and the composite materials were characterized using XRD,UV-Vis,TEM,and EDS.The composite materials were used as a surface-enhanced Raman scattering(SERS)substrate and a new method for detecting levofloxacin was developed using a standard working curve.Spiked recovery experiments were also conducted.In addition,the mechanism of Fe₃O₄-Au-Ag enhancing Raman spectrum of levofloxacin was analyzed.There is a relatively good linear relationship between the SERS peak intensity and the logarithm of levofloxacin concentration(10^-7~10^-3mol/L).The standard working curve equation is y=957x+7516.2,and the correlation coefficient R² is 0.9522.This method has good stability with a relative standard deviation of 2.2%,and its sensitivity is relatively high with a detection limit of 2×10^-9mol/L and spiked recovery rate of over 93%.The mechanism of Fe₃O₄-Au-Ag enhancing Raman spectrum of levofloxacin includes electromagnetic enhancement mechanism,chemical enhancement mechanism,and three enhancement models(mirror model,antenna model,and lightning rod model).This new method is expected to be used in such fields as agriculture,industry,environment,food,medicine,and health,achieving highly sensitive detection of antibiotics in actual samples.

2025年3月17日,湖南省市场监督管理局发布《2023年度湖南省知识产权战略推进专项项目验收、评估结果的通报》,长沙有色冶金设计研究院有限公司(简称长沙有色院)承担的“Online SAR工程灾害智能监测雷达系统研发及知识产权密集型产业培育”项目顺利通过验收,被评为“优秀”等级。“Online SAR工程灾害智能监测雷达系统研发及知识产权密集型产业培育”项目于2023年7月获批立项。

根据中国有色金属工业协会和中国有色金属学会联合发布的《关于颁发2024年度有色金属工业科学技术奖的通知》,长沙有色冶金设计研究院有限公司(简称长沙有色院)获中国有色金属工业科学技术奖一等奖2项,二等奖5项。“沉积型软破围岩铝土矿床顶板安全管控综合技术研究与应用”“人机物共融的有色冶炼流程精细管控关键技术与应用”2项成果获中国有色金属工业科学技术奖一等奖,“高锗锌精矿锗高效提取及高纯化合物制备技术与应用”“炼锌渣绿色协同处置及资源高效利用技术与应用”“矿山重大危险源无人自动安全巡检系统”“超深井绿色安全膏体充填新技术研究与应用”“铜镍钴高效浸取与综合利用技术”5项成果获中国有色金属工业科学技术奖二等奖。