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激光清洗技术研究进展及挑战(特邀)

中国激光 2024年第4期51卷 89-112页

作者：朱国栋张东赫李志超苏轩金阳徐杰单德彬郭斌哈尔滨工业大学微系统与微结构制造教育部重点实验室黑龙江哈尔滨150080 哈尔滨工业大学机电工程学院黑龙江哈尔滨150001 哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001 哈尔滨工业大学(深圳)材料科学与工程学院广东深圳518055 哈尔滨工业大学激光制造研究中心河南郑州450046

开展激光高效清洗基础理论及装备的研究是对《中国制造2025》纲要的具体落实,符合我国可持续发展战略,有利于提高航空航天、轨道交通、海洋船舶等装备的自动化程度,对于我国产业结构的升级与优化具有重要意义。尽管国外发达国家在激光... 详细信息

开展激光高效清洗基础理论及装备的研究是对《中国制造2025》纲要的具体落实,符合我国可持续发展战略,有利于提高航空航天、轨道交通、海洋船舶等装备的自动化程度,对于我国产业结构的升级与优化具有重要意义。尽管国外发达国家在激光清洗的基础理论、工艺探索、工程应用方面开展了大量的工作,但仍普遍存在构件清洗效率低、耦合机制不清晰、评价标准和在线监测技术有待完善等问题。针对我国航天、高铁、海洋等领域对激光清洗的重大需求,以航天新一代固液冲压发动机的TA15钛合金进气道、高铁车体特征件和转向架零部件、海洋船舶制造中的舱口盖等大型复杂构件为研究对象,介绍了激光清洗机制及工艺、清洗过程中多元参数的在线监测、清洗智能装备技术等方面的研究进展,以期为我国未来智能激光制造的可持续发展提供一定参考。

关键词：激光技术激光清洗清洗机制智能选区工程应用

3-D RIGID PLASTIC FEM SIMULATION OF EXTRUDING-BULGING PROCESS OF TEE TUBES

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中国有色金属学会会刊：英文版 1999年第2期9卷 45-50页

作者： Wang, Chenlu shan, debin Lu, Yan Harbin Inst of Technology Harbin China

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｅｅｔｕｂｅｓａｒｅｗｉｄｅｌｙａｐｐｌｉｅｄａｓｉｍｐｏｒｔａｎｔｐｉｐｅｊｕｎｃｔｉｏｎｓｉｎｐｉｐａｇｅｉｎａｌｋｉｎｄｓｏｆｉｎｄｕｓｔｒｙｄｅｐａｒｔｍｅｎｔｓ．Ｗｉｔｈｔｈｅｄ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｅｅｔｕｂｅｓａｒｅｗｉｄｅｌｙａｐｐｌｉｅｄａｓｉｍｐｏｒｔａｎｔｐｉｐｅｊｕｎｃｔｉｏｎｓｉｎｐｉｐａｇｅｉｎａｌｋｉｎｄｓｏｆｉｎｄｕｓｔｒｙｄｅｐａｒｔｍｅｎｔｓ．Ｗｉｔｈｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｉｎｄｕｓ...

关键词： FEMextrudingbulging processtee tubes

Quasi Ellipsoid Gear Surface Reconstruction Based on Meshless Local Petrov-Galerkin Method and Transmission Characteristic

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 788-792页

作者： WU Xuemei shan debin LI Guixian School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150006 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150006 China

Special transmission 3D model simulation must be based on surface discretization and reconstruction, but special transmission usually has complicated tooth shape and movement, so present software can＇t provide technical support for special transmission 3D model simulation. Currently, theoretical calculation and experimental method are difficult to exactly solve special transmission contact analysis problem. How to reduce calculation and computer memories consume and meet calculation precision is key to resolve special transmission contact analysis problem. According to 3D model simulation and surface reconstruction of quasi ellipsoid gear is difficulty, this paper employes meshless local Petrov-Galerkin （MLPG） method. In order to reduce calculation and computer memories consume, we disperse tooth mesh into finite points--sparseness points cloud or grid mesh, and then we do interpolation reconstruction in some necessary place of the 3D surface model during analysis. Moving least square method （MLSM） is employed for tooth mesh interpolation reconstruction, there are some advantages to do interpolation by means of MLSM, such as high precision, good flexibility and no require of tooth mesh discretization into units. We input the quasi ellipsoid gear reconstruction model into simulation software, we complete tooth meshing simulation. Simulation transmission ratio during meshing period was obtained, compared with theoretical transmission ratio, the result inosculate preferably. The method using curve reconstruction realizes surface reconstruction, reduce simulation calculation enormously, so special gears simulation can be realized by minitype computer. The method provides a novel solution for special transmission 3D model simulation analysis and contact analysis.

关键词： meshless local Petrov-Galerkin method moving least square method quasi ellipsoid gear tooth mesh simulation

Effect of Microstructure on Thermal Expansion Coeffcient of 7A09 Aluminum Alloy

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Journal of Materials Science & Technology 2011年第9期27卷 797-801页

作者： Hongzhi Ji Lin Yuan debin shan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The relationship between microstructure evolution and coefficient of thermal expansion （CTE） of 7A09 aluminum alloy was investigated in this paper. Differential scanning calorimetry （DSC） was combined with transmission electron microscopy （TEM） and high-resolution transmission electron microscopy （HRTEM） to investigate microstructure evolution taking place in 7A09 aluminum alloy during heating and cooling process. The corresponding CTE curves of the 7A0g alloy were recorded by thermal dilatometer. Results indicated that GPII zones and Ur phase were main precipitates in the highest strength tempered （T6） 7A09 alloy. The r/phase was the main participate in 7A09 alloy during the cooling process. The nonlinear dependency existed between CTE and temperature in both changing temperature processes. During the heating process, obvious additional contraction of alloy volume was directly caused by phase transition, such as dissolution of η＇ phase, transition from η＇ to η phase and dissolution of η phase. The additional contraction could slow down the increase of CTE greatly and be expressed in the nonlinearity of CTE curve. Volume and energy changes of alloy system influenced the variation trend of CTE directly, which was caused by the precipitation of U phase during the cooling process. These effects were revealed by the corresponding nonlinear change of CTE.

关键词： Aluminum Coefficient alloy Changing temperature process Microstructure evolution of thermal expansion

Mechanism and morphology evolution of the O phase transformation in Ti-22Al-25Nb alloy

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Journal of Materials Science & Technology 2021年第30期89卷 97-106页

作者： Zong Yingying Wang Jiwei Shao Bin Tang Wei shan debin National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin150001China

The phase transformation and microstructure in Ti-22Al-25Nb alloy are extremely *** this work,the morphology evolution of the O phase during the heating and cooling process was investigated by electron backscatter diffraction(EBSD)and first-principles *** results show that the O→α_(2)phase transformation process during the heating process is as follows:spheroidization of the O phase occurs first,then theα_(2)phase nucleates in the spheroidized O phase,grows and replaces the O phase,completing the O→α_(2)phase *** the meanwhile,the diffusion of Nb from Nb-poor O to Nb-rich B2 phases is a back-diffusion *** to first-principles calculations,the driving force of the O→α_(2)phase transformation is the difference in the free energies of formation for the two phases(0.09 eV/atom).When the Nb content is greater than 15.625%,the lattice distortion of theα_(2)phase sharply increases,and the distortion energy drives the back-diffusion of *** the cooling process,theα_(2)→O phase transformation is difficult and slow due to the difficult diffusion of Nb from the B2 toα_(2)*** holding for 60 min at 960℃,the coarseα_(2)phase gradually transforms to the O phase from the margin to the inside,forming a dispersed mixed structure of the O andα_(2)*** the B2→O transformation,the nucleation of the O phase induces a high stress region,in the range of approximately 200 nm.

关键词： Ti-22Al-25Nb alloy Phase transformation Microstructure O phase First-principles

Metal flow hysteresis behavior and shape control strategy during porthole die extrusion of micro heat pipe

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Chinese Journal of Aeronautics 2023年第7期36卷 268-281页

作者： Yongda LIU Jie XU Xiaoliang WANG debin shan Bin GUO Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of TechnologyHarbin 150080China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The shape control strategy of micro grooves is still unclear and challenging during the porthole die extrusion of grooved micro heat pipe(MHP).Through the simulation and experiment of porthole die extrusion of a MHP profile,the metal flow hysteresis behavior within micro features and the effect of ram speed and extrusion temperature on it and the resulting forming integrity was ***,Taguchi design and variance analysis(ANOVA)were introduced to determine their influence magnitude on the metal flow uniformity calculated by simulation *** main findings are given *** metal flow hysteresis derives from part feature size *** negligible friction-affected area during conventional extrusion severely slows down the metal flow within micro features during the MHP profile extrusion,which is due to the surge in the area ratio of the friction-affected area to the region in which it is *** ram speed nor extrusion temperature can change the distribution of the friction-affected ***,increasing ram speed multiplies the metal flow hysteresis and severely reduces the forming integrity,whereas extrusion temperature has little *** this strategy,batch extrusion of the profile with microgrooved width of 0.27±0.02 mm was achieved in industrialized conditions.

关键词： Micro heat pipe Microforming Size effect Porthole die extrusion Metal flow Forming integrity Microstructure

Microstructure evolution and mechanical anisotropy of M50 steel ball bearing rings during multi-stage hot forging

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Chinese Journal of Aeronautics 2021年第11期34卷 254-266页

作者： Hongwei JIANG Yanran SONG Yucheng WU debin shan Yingying ZONG National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China AECC Harbin Bearing Co. LtdHarbin 150070China

This study aimed to explore the evolution of flow lines and microstructures of M50-steel bearing ring and the anisotropy of its tensile mechanical properties after Multi-Stage Hot Forging(MSHF) and subsequent spheroidizing annealing(MSHFA). To this end, the present study mainly employed stereo microscopy, Optical Metallurgical Microscopy(OMM), Scanning Electron Microscopy(SEM), and Electron Backscatter Diffraction(EBSD) to characterize and analyze the workpiece at each processing stage of MSHF while performing microhardness measurement and uniaxial tensile experiment to test and analyze the mechanical properties of the workpiece. Macro-structure observation showed that the simulation results of flow lines at each stage were consistent with the experimental results. Microscopic observation showed that, after MSHF, deformation gradually became less significant along the outward radial direction of the bearing ring. After MSHFA,the microstructures of the bearing ring became uniform, whereas primary carbides did not *** mechanical properties were better in the axial direction(AD) than in the radial(RD) and circumferential directions(CD) after MSHF due to the smaller grain width. After MSHFA, the mechanical properties in the ADs and CDs were better than those in the RDs, which was due to the large cross-sectional area of carbides along the flow-line direction.

关键词： Bearing ring Flow lines Forging Mechanical anisotropy Microstructure evolution

Dose rate effects on shape memory epoxy resin during 1 Me V electron irradiation in air

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Journal of Materials Science & Technology 2021年第8期67卷 61-69页

作者： Longyan Hou Yiyong Wu debin shan Bin Guo Yingying Zong State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Materials Behavior and Evaluation Technology in Space Environments Harbin Institute of TechnologyHarbin 150001China

The effects of 1 Me V electron irradiation in air at a fixed accumulated dose and dose rates of 393.8,196.9,78.8,and 39.4 Gy s^(-1)on a shape memory epoxy(SMEP)resin were *** low-dose-rate irradiation,accelerated degradation of the shape memory performance was observed;specifically,the shape recovery ratio decreased exponentially with increasing irradiation time(that is,with decreasing dose rate).In addition,the glass transition temperature of the SMEP,as measured by dynamic mechanical analysis,decreased overall with decreasing dose *** dose rate effects of 1 Me V electron irradiation on the SMEP were confirmed by structural analysis using electron paramagnetic resonance(EPR)spectroscopy and Fourier transform infrared(FTIR)*** EPR spectra showed that the concentration of free radicals increased exponentially with increasing irradiation ***,the FTIR spectra showed higher intensities of the peaks at 1660 and 1720 cm^(-1),which are attributed to stretching vibrations of amide C=O and ketone/acid C=O,at lower dose *** intensities of the IR peaks at 1660 and 1720 cm^(-1) increased exponentially with increasing irradiation time,and the relative intensity of the IR peak at 2926 cm^(-1)decreased exponentially with increasing irradiation *** solid-state13 C nuclear magnetic resonance(NMR)spectra of the SMEP before and after 1 Me V electron irradiation at a dose of 1970 k Gy and a dose rate of 78.8 Gy s^(-1) indicated damage to the CH_(2)–N groups and aliphatic isopropanol *** result is consistent with the detection of nitrogenous free radicals,a phenoxy-type free radical,and several types of pyrolytic carbon radicals by *** the subsequent propagation process,the free radicals produced at lower dose rates were more likely to react with oxygen,which was present at higher concentrations,and form the more destructive peroxy free radicals and oxidation products such as acids,amides,and *** increase in peroxy

关键词： Shape memory epoxy resin Shape memory effect Electron irradiation Dose rate effect Free radical Chain scission

Effect of power spinning and heat treatment on microstructure evolution and mechanical properties of duplex low-cost titanium alloy

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Journal of Materials Science & Technology 2023年第5期136卷 121-139页

作者： Zhongze Yang Wenchen Xu Weiqing Zhang Yu Chen debin shan National Key Laboratory for Precision Hot Processing of Metals&School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The microstructural evolution and mechanical properties of low-cost Ti-5.5Al-1Fe-3.5Cr-3.2Zr-0.2Si al-loy during power spinning and after three types of heat-treatment routines(low-temperature anneal-ing,high-temperature annealing,solution and annealing)were systematically *** effective heat-treatment routine to fabricate high-strength and acceptable ductile as-spun Ti-5.5Al-1Fe-3.5Cr-3.2Zr-0.2Si alloy tubes was then proposed whereby the relationship between the mechanical performances and mi-crostructures was ***{0002}_(α)and{001}_(β)textures were formed after multi-pass power *** as-spun LC-Ti alloy exhibited a good combination of strength and elongation after heat treat-ment at 550℃for 4 h,which was ascribed to the large plastic induced low-temperature spheroidization of deformedαphase and nanoscaleαprecipitation from deformedβ***,the elongation de-creased evidently when Zr2Si/TiCr2 participated at the interphase boundaries after heat treatment at 550℃for 8 *** high-temperature annealing,the elongation changed nonlinearly owing to the precipitation of Zr2Si particles at triangular grain boundaries treated at 750℃for 1 h,and the spheroidization of the deformedα_(p)*** solution and annealing conditions,lenticularαs would participate from the metastableβgrains,which contributed to the greatest strength albeit poor *** study provides an effective guidance for the processing and application of the low-cost titanium alloy.

关键词： Low-cost titanium alloy Power spinning Heat treatment Microstructure evolution Mechanical property