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Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao HOU Kai HOU Xiaopeng wang hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was *** non-equilibrium solidification structure of the under cooled alloy samples were *** is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling *** and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were ***-density defects were observed,such as dislocations,stacking faults networks,and twinning *** standard FCC diffraction pattern represents that it is still a single-phase *** on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced *** addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was *** was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear *** electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

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High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model

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Defence Technology（防务技术） 2024年第2期32卷 553-571页

作者： Xu Li Yan Liu Junbo Yan Zhenqing Shi hongfu wang Yingliang Xu Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China China Research and Development Academy of Machinery Equipment Beijing100089China

The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 *** study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic *** the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/*** erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered *** examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration ***,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation ***,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present *** upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or *** to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit.

关键词： High-speed penetration Concrete target Erosion Projectile nose evolution model

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Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

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Defence Technology（防务技术） 2024年第2期32卷 596-618页

作者： hongfu wang Yan Liu Fan Bai Chao He Yingliang Xu Qiang Zhou Chuan Xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation *** research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

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电加热服加热区域分布对人体热舒适感的影响

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纺织学报 2024年第4期45卷 188-194页

作者：柯莹林磊郑晴王宏付江南大学设计学院江苏无锡214122 江南大学纺织科学与工程学院江苏无锡214122

为探究加热区域分布对电加热服热舒适性的影响规律,设计了3种加热区域,在环境温度为(5±0.5)℃,相对湿度为(50±5)%的条件下进行真人着装实验,记录受试者客观生理数据和主观感受并对其进行分析。实验结果表明:在加热面积一定的情况下,... 详细信息

为探究加热区域分布对电加热服热舒适性的影响规律,设计了3种加热区域,在环境温度为(5±0.5)℃,相对湿度为(50±5)%的条件下进行真人着装实验,记录受试者客观生理数据和主观感受并对其进行分析。实验结果表明:在加热面积一定的情况下,将加热片集中分布在上半身躯干位置能显著提高平均躯干温度,对平均皮肤温度的提高作用不大;相比之下,躯干加上腿部的加热区域组合能有效提高平均皮肤温度0.8℃以上,躯干、大腿和大臂的加热区域组合能将平均皮肤温度提高0.5℃;另外,将加热片分布到四肢相较于集中加热躯干对改善热感觉和热舒适的效果更好。建议当加热面积一定时,将加热片分布到躯干以及腿部位置,可使电加热服具有较好的功能性和舒适性。

关键词：电加热服加热区域皮肤温度热感觉热舒适性

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Refinement Mechanism of Microstructure of Undercooled Nickel Based Alloys

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1041-1047页

作者：杜文华 HOU Kai XU Xuguang Ismal Saad Willey Liew Yun Hsien AN Hongen Nancy Julius Siambun Bih-Lii Chuab 王洪福 College of Mechanical Engineering North University of ChinaTaiyuan 030051China Faculty of Engineering University Malaysia SabahKota Kinabalu 88400Malaysia

Through the use of purification and recirculation superheating techniques on molten glass,the Ni65Cu33Co2 alloy was successfully undercooled to a maximum temperature of 292 ***-speed photography was employed to capture the process of interface migration of the alloy liquid,allowing for an analysis of the relationship between the morphological characteristics of the alloy liquid solidification front and the degree of ***,the microstructure of the alloy was examined using metallographic microscopy,leading to a systematic study of the microscopic morphological characteristics and evolution laws of the refined structure during rapid *** research reveals that the grain refining mechanism of the Ni-Cu-Co ternary alloy is consistent with that of the binary alloy(Ni-Cu).Specifically,under low undercooling conditions,intense dendritic remelting was found to cause grain refinement,while under high undercooling conditions,recrystallization driven by accumulated stress and plastic strain resulting from the interaction between the liquid flow and the primary dendrites caused by rapid solidification was identified as the main factor contributing to grain ***,the study highlights the significant role of the Co element in influencing the solidification rate and reheat effect of the *** addition of Co was also found to facilitate the formation of non-segregated solidification structure,indicating its importance in the overall solidification process.

关键词： grain refinement recalescence recrystallization undercooling

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焊接残余应力对钢桥面疲劳性能的影响与处理措施

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哈尔滨工业大学学报 2024年第3期56卷 29-37页

作者：郑凯锋冯霄暘何晓晖衡俊霖李乐王洪福西南交通大学土木工程学院成都610036 深圳市市政设计研究院有限公司广东深圳518060 深圳大学土木与交通工程学院广东深圳518060 代尔夫特理工大学土木工程与地球科学学院荷兰代尔夫特2628 CN 中建五洲工程装备有限公司南京210046

为改善正交异性钢桥面的抗疲劳性能,对钢桥面进行退火处理以降低关键焊缝的焊接残余应力。首先系统性地回顾和探讨钢桥面焊接残余应力分布模式,同时就残余应力对疲劳裂纹发展的影响进行了文献分析。随后,归纳和总结了国内外主流焊接残... 详细信息

为改善正交异性钢桥面的抗疲劳性能,对钢桥面进行退火处理以降低关键焊缝的焊接残余应力。首先系统性地回顾和探讨钢桥面焊接残余应力分布模式,同时就残余应力对疲劳裂纹发展的影响进行了文献分析。随后,归纳和总结了国内外主流焊接残余应力消除方法,并开展对比分析。借鉴压力容器制造方法,建议在正交异性钢桥面制造中引入退火处理工艺以降低焊接残余应力。研究聚焦钢桥面中疲劳问题较突出的顶板与U肋连接焊缝,设计了16个(其中9个退火处理,7未作处理)局部足尺单U肋试件进行残余应力测试与疲劳试验。试验结果表明,退火处理后焊缝残余应力实测值降低约80%,疲劳强度提高约23%。可以看出,退火处理可以大幅降低焊接残余应力,从而有效提升钢桥面抗疲劳性能。

关键词：桥梁工程正交异性钢桥面焊缝退火处理焊接残余应力疲劳开裂

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Influence of Yttria Stabilized Zirconia and Hydrothermal Treatment on Plasma Sprayed Hydroxyapatite Coatings

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 449-454页

作者： wang hongfu TIAN Xiaoguang REN Xiaozhong College of Mechanical and Electronic Engineering Huanghe Jiaotong UniversityJiaozuo 454950China Henan Engineering Technology Research Center on Intelligent Manufacturing Technology and Equipment Jiaozuo 454950China

A post-treatment of hydrothermal process was conducted to evaluate its effects on the material characteristics and mechanical properties of plasma-sprayed pure HA and HA/20% YSZ *** morphology and microstructural changes,relative element contents as well as phase transformations were analyzed by scanning electron microscopy,energy dispersive spectroscopy,and X-ray *** microhardness and Young’s modulus were ***3 was found existing before and after the whole process of *** of impurity phases such as CaO,TCP,and TTCP of as-sprayed coatings were observed to disappear while HA peaks show a tendency of getting higher and wider over *** morphology of SEM analysis presents a clear deposition behavior of ultrafine HA crystallized particles and cross-sectional analysis exhibits a dense and fine *** properties of HA/20%YSZ coatings are found to be significantly higher than those of pure HA coatings and both of which displayed an overall increase with the heating time,indicating enhanced performances.

关键词： plasma spraying hydroxyapaptite hydrothermal treatment composite coating

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Microstructure evolution and grain refinement mechanism of rapidly solidified single-phase copper based alloys

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Journal of Materials Science & Technology 2022年第33期128卷 160-179页

作者： Xiaolong Xu Cheng Tang hongfu wang Yukang An Yuhong Zhao College of Materials Science and Engineering School of Mechanical EngineeringNorth University of ChinaTaiyuanShanxi 030051China

The Cu65Ni35,Cu60Ni40 and Cu55Ni45 alloys were undercooled by fluxing method,and the rapid solidification structure with different undercoolings were also *** the same time,the interface migration process during rapid solidification was photographed by high-speed photography,and the relationship between the morphological characteristics of solidification front and undercooling was *** microstructures of the three alloys were observed by metallographic microscope,and the microstructure characteristics and evolution law were systematically *** was found that two grain refinement events occurred in the low undercooling range and high undercooling range,*** EBSD test of grain refined microstructures showed that the microstructure in the low undercooling range has a high proportion of low-angle grain boundaries and high strength ***,there were a large proportion of high-angle grain boundaries and a high proportion of twin grain boundaries and more randomly oriented grains in the microstructure in the high undercooling *** TEM test of the Cu55Ni45 alloy with the maximum undercooling of 284 K showed that there were high-density dislocation networks and stacking faults in the ***,the evolution relationship between microstructure hardness and undercooling was systematically *** was found that the microhardness of the three alloys decreased sharply near the critical *** with EBSD,TEM and microhardness analysis,it was confirmed that the grain refinement under low undercooling was caused by dendrite remelting,while the grain refinement under high undercooling was caused by stress-induced recrystallization.

关键词： Rapid solidification structure Grain refinement Dendrite remelting Recrystallization

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基于改进粒子群算法的四旋翼BSMRC优化策略

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兵器装备工程学报 2024年第4期45卷 238-246页

作者：任恩泽曾庆华宋甫俊田大江郭运伟王宏福中山大学航空航天学院广东深圳518107

针对四旋翼无人机反步滑模鲁棒控制器(BSMRC)因参数整定困难而限制其工程应用的问题,设计了一种基于改进粒子群算法(IPSO)的BSMRC参数优化策略。建立了含未知扰动的无人机非线性模型并设计了补偿未知扰动的BSMRC,通过Lyapunov第2方法对... 详细信息

针对四旋翼无人机反步滑模鲁棒控制器(BSMRC)因参数整定困难而限制其工程应用的问题,设计了一种基于改进粒子群算法(IPSO)的BSMRC参数优化策略。建立了含未知扰动的无人机非线性模型并设计了补偿未知扰动的BSMRC,通过Lyapunov第2方法对系统稳定性进行了证明。接着,从惯性权重和学习因子两方面对经典PSO算法改进,提升了其收敛速度,在此基础上自动整定了BSMRC参数。通过仿真表明了IPSO可使BSMRC参数快速收敛到最优解。通过模块化编程及自动代码生成技术将最优BSMRC算法部署至Pixhawk 4飞控进行了飞行实验,结果表明了IPSO优化策略的有效性,体现出了BSMRC的强鲁棒性和抗扰性。该优化策略解决了无人机BSMRC参数整定效率低下的问题,并采用基于模型设计(model-based design,MBD)技术提高了无人机控制系统的开发效率。

关键词：四旋翼无人机反步滑模鲁棒控制器姿态控制 IPSO算法 Lyapunov方法参数优化整定 MBD

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Mineralogical and Active Mechanical Excitation Characteristics of Filled Fly Ash Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2017年第2期32卷 413-416页

作者：杜雨婷 wang hongfu wang Zhongchang wang Zechuan XIA Hongchun School of Mechanical and Power Engineering North University of China Taiyuan 030051 China School of Civil and Safety Engineering Dalian Jiaotong University Dalian 116028 China College of Civil and Architectural Engineering Dalian University Dalian 116622 China

To reveal the influence of mechanical activation on the performance of fly ash, the microanalysis（the energy spectroscopy, XRD and SEM）, the distribution size of particle of fly ash and cement paste intensity of various age for different grinding time were studied. The relationships of the activity and the composition of fly ash, microstructure and the distribution of particle size by mechanical activation of fly ash were obtained. The internal glass beads with activity were released by grinding fly ash for a certain time. The particle specific surface area was improved and the hydration reaction of the interface and the surface active center was increased by grinding. The granularity distributing of fly-ash trended towards optimization. The polar molecules or ions were easier to intrude into the internal cavity of the vitreous body. The active silica and alumina of fly ash were rapidly depolymerized. Each performance index of fly ash was increased before grinding for 20 min. Cement paste intensity of various age increased along with the grinding time, and the early strength increase range was big, but the later period intensity increase range hastened slightly. The internal part of vitreous of fly ash was destroyed if the fly ash continued to be ground and the activity of fly ash was reduced. It is suggested that Guozhuang＇s fly ash should be ground for 20 min.

关键词： fly ash mineral composition the distribution of particle size milling time activity

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