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Design and grindability assessment with cup shaped electroplated CBN wheel grinding turbine disc slots of powder metallurgy superalloy FGH96

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Chinese Journal of Aeronautics 2024年第9期37卷 521-534页

作者： Benkai li Wenfeng DING YeJun ZHU changhe li Yanbin ZHANG Min YANG Xiao MA Mingzheng liU Xin CUI School of Mechanical Engineering Qingdao University of TechnologyQingdao 266520China National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Engineering Nanjing Agricultural UniversityNanjing 210031China

The machining surface integrity of aero-engine turbine disc slots has a significant impact on their fatigue life and service performance,and achieving efficiency and high-precision machining is still a great *** high machining requirements of future aeroengine turbine disc slots will be difficult to satisfy using the broaching *** addition,existing methods of slot machin-ing face difficulties in ensuring surface *** study explored a cup shaped electroplated Cubic Boron Nitride(CBN)abrasive wheel for profile grinding the turbine disc slots of FGH96 powder metallurgy *** matrix structure of the cup shaped abrasive wheel was designed and verified.A profile grinding experiment was conducted for fir-tree slots on a five-axis machining *** accuracy and the surface integrity were *** show that the key dimension detection results of the slots were within the allowable tolerance ***,an average sur-face roughness Ra of 0.55μm was achieved,the residual stress was compressive,the plastic defor-mation layer thickness was less than 5μm,and the hardening layer thickness was less than 20μ*** research findings provide a new approach to machining the slots of aviation engine turbine discs and guidance for the high-quality processing of complex components.

关键词： Profile grinding Surface integrity Cup shaped CBN abrasive wheel Turbine disc slots FGH96

Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 115-136页

作者： Yusuf Suleiman Dambatta changhe li Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai li Anxue Chu Mingzheng liu Yanbin Zhang Zafar Said Zongming Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Mechanical Engineering Department Ahmadu Bello UniversityZaria 810106Nigeria Mechanical Engineering Department University of Malaya50603 Kuala LumpurMalaysia Department of Mechanical Engineering King Fahd University of Petroleum&Minerals31261 DhahranSaudi Arabia State Key Laboratory of Ultra-Precision Machining Technology Department of Industrial and Systems Engineer-ingThe Hong Kong Polytechnic UniversityHong KongChina College of Engineering University of Sharjah27272 SharjahUnited Arab Emirates Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China

Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining *** involve the spray of an infinitesimal amount of mist-like lubricants during machining *** MQL system is affirmed to exhibit an excellent machining performance,and it is highly *** nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL *** have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these *** work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)*** effect different grinding modes and lubrication systems during the grinding operation was also *** concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower *** quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface *** was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication ***,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%***,regression analysis was used to obtain an optimum parameter *** observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.

关键词： Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants Nanofluid Grinding Ceramic

Force model in electrostatic atomization minimum quantity lubrication milling GH4169 and performance evaluation

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Frontiers of Mechanical Engineering 2024年第4期19卷 55-72页

作者： Min YANG Hao MA Zhonghao li Jiachao HAO Mingzheng liU Xin CUI Yanbin ZHANG Zongming ZHOU Yunze LONG changhe li School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China College of Physics QingdaoUniversityQingdao 266071China Hanergy Lubrication Technology Co. Ltd.Qingdao 266200China

The nickel-based high-temperature alloy GH4169 is the material of choice for manufacturing critical components in aeroengines,and electrostatic atomization minimum quantity lubrication(EMQL)milling represents a fundamental machining process for ***,the effects of electric field parameters,jet parameters,nozzle position,and milling parameters on milling performance remain unclear,which constrains the broad application of EMQL in aerospace *** study evaluated the milling performance of EMQL on nickel-based alloys using soybean oil as the lubrication *** revealed that compared with conventional pneumatic atomization MQL milling,EMQL reduced the milling force by 15.2%-15.9%,lowered the surface roughness by 30.9%-54.2%,decreased the average roughness spacing by 47.4%-58.3%,and decreased the coefficient of friction and the specific energy of cutting by 55%and 19.6%,*** optimization experiments using orthogonal arrays demonstrated that air pressure most significantly affected the milling force and specific energy of cutting,with a contribution rate of 22%,whereas voltage had the greatest effect on workpiece surface roughness,contributing 36.71%.Considering the workpiece surface morphology and the potential impact of droplet drift on environmental and health safety,the optimal parameter combination identified were a flow rate of 80 mL/h,an air pressure of 0.1 MPa,a voltage of 30 kV,a nozzle incidence angle of 35°,an elevation angle of 30°,and a target distance of 40 *** research aimed to provide technical insights for improving the surface integrity of aerospace materials that are difficult to machine during cutting operations.

关键词： electrostatic atomization MQL nickel-based alloys milling force surface roughness force model

脱液型管式气液分离器旋流分离段内液膜流动和分离特性

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化工进展 2024年第8期43卷 4297-4306页

作者：宋家恺孔令真陈家庆孙欢李奇李长河王思诚孔标北京石油化工学院环境工程系北京102617 深水油气管线关键技术与装备北京市重点实验室北京102617 中国石化石油勘探开发研究院北京102617

脱液型管式气液分离器旋流分离段内液膜流动特性是影响分离性能的关键因素,掌握液膜流动与分离效率之间的关系对结构改进和性能提升至关重要。本文改变液气比、入口气速、分流比和旋流叶片出口角等因素开展室内实验测试,获得不同工况下... 详细信息

脱液型管式气液分离器旋流分离段内液膜流动特性是影响分离性能的关键因素,掌握液膜流动与分离效率之间的关系对结构改进和性能提升至关重要。本文改变液气比、入口气速、分流比和旋流叶片出口角等因素开展室内实验测试,获得不同工况下液膜流动的高速摄影图像和分离效率,基于Matlab编程建立液膜表面波速度和角度的图像分析方法,确定液膜流动特性与分离效率之间的关系。结果表明,液气比在0.12~0.3L/m3范围内,液气比和分流比对分离效率和液膜表面波速度的影响不明显;入口气速对分离效率和液膜表面波速度的影响最为显著,随着入口气速逐渐增加,分离效率先增大后减小,在入口气速18.82m/s时出现拐点;旋流叶片出口角分别为30°、45°、60°时,分离效率由大到小依次为30°>45°>60°,液膜表面波速度由大到小依次为60°>45°>30°。总的来说,旋流分离管段内液膜表面波速度0.98m/s为临界值,液膜表面波速度大于该值时,环缝排液口处液膜更易发生破碎,部分破碎的大液滴在重力和气流作用下进入气相出口,导致气液分离效率显著下降;液膜表面波速度小于0.98m/s时,分离效率基本保持在98%以上。

关键词：气液分离液膜流动特性液膜表面波速度分离效率

磁力牵引纳米润滑剂微量润滑磨削力模型与验证

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机械工程学报 2024年第9期60卷 323-337页

作者：崔歆李长河张彦彬杨敏周宗明刘波王春锦青岛理工大学机械与汽车工程学院青岛266520 汉能(青岛)润滑科技有限公司青岛266200 四川明日宇航工业有限责任公司什邡618400 香港理工大学超精密加工技术国家重点实验室中国香港999077

磨削是获得航空航天难加工材料高表面质量和加工精度不可或缺的方法,尤其是以大切削弧长为特点的高效率磨削在航空航天领域获得广泛的应用。但是,润滑剂在大切削弧长工件/磨粒界面牵引动力不足,导致浸润性能和冷却润滑缺失、工件表面完... 详细信息

磨削是获得航空航天难加工材料高表面质量和加工精度不可或缺的方法,尤其是以大切削弧长为特点的高效率磨削在航空航天领域获得广泛的应用。但是,润滑剂在大切削弧长工件/磨粒界面牵引动力不足,导致浸润性能和冷却润滑缺失、工件表面完整性恶化。基于此,提出磁力牵引纳米润滑剂微量润滑磨削新工艺,但磁场作用下的磁性纳米润滑剂微界面浸润动力学尚不明确,磁场力赋能作用下的磨削力模型尚未建立。首先,揭示磨削区磁力牵引润滑剂输运动力学规律,建立磁场作用下的润滑剂浸润速度与流量模型。其次,提出基于截角六面体磨粒几何模型的砂轮建模方法,揭示单颗磨粒力学行为并建立切削力数学模型。最后,进行磁力牵引纳米润滑剂微量润滑磨削钛合金磨削力模型的实验验证。结果表明,磁力牵引纳米润滑剂微量润滑磨削新工艺能显著提升润滑剂浸润速度和流量,相比无磁场,磁场强度为5×10^(5) A/m时法向和切向磨削力分别降低31.8%和74.3%;磨削力预测值与试验值吻合度较好,切向和法向磨削力最小平均偏差分别为9.2%和5.7%。研究为磁力牵引纳米润滑剂微量润滑磨削提供理论依据,为难加工材料的大弧长磨削的高表面完整性要求提供技术支持。

关键词：磨削磁性纳米润滑剂磁力牵引动力学行为力学模型

Urban land expansion and arable land loss of the major cities in China in the 1990s

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Science China Earth Sciences 2005年第9期48卷 1492-1500页

作者： TAN Minghong li Xiubin LU changhe Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land of 145 cities with the largest areas in 1990 and arable land patches around these cities. With these data, this paper analyzes the characteristics of ur- ban construction land expansion and the consequent arable land loss in East, Middle and West China, and further identifies the social, economic and spatial factors of the urban land use changes, using GIS (Geographical Information System) and multivariate regression approaches. The results show that total urban land of the 145 cities expanded by 39.8%, with about 70% of the new urban land converted from arable land in the 1990s. The urban land expansion varied among the three regions, with a value of 43.0% in the East, 33.1% in the West (33.1%) and 17.8% in the Middle. Moreover, mean urban construction land per capita increased by10.7% in the East, but it decreased by 7.7% in the Middle, 1.4% in the West. Statistical analysis indicated that total wages of staff and workers could best explain the differences of urban land expansion.

关键词： China, urban construction land expansion, arable land loss, regional difference, neighboring index [I(i)].

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近海黏性土中桩土界面剪切特性与含水率效应

地下空间与工程学报 2024年第4期20卷 1236-1246页

作者：王永洪王鑫张明义李长河王东雷青岛理工大学土木工程学院山东青岛266520 青岛理工大学机械与汽车工程学院山东青岛266520 青岛永元海洋科技有限公司山东青岛266533 青岛绿色理工岩土工程有限公司山东青岛266533

为了研究粉质黏土-混凝土截面的抗剪强度在不同物理条件下的影响特征,本文针对粗糙度、含水率对其的影响展开研究,根据前人经验总结自制出了型直剪试验仪,研究了混凝土在不同粗糙度以及不同含水率的条件下,粉质黏土-混凝土界面的剪切特... 详细信息

为了研究粉质黏土-混凝土截面的抗剪强度在不同物理条件下的影响特征,本文针对粗糙度、含水率对其的影响展开研究,根据前人经验总结自制出了型直剪试验仪,研究了混凝土在不同粗糙度以及不同含水率的条件下,粉质黏土-混凝土界面的剪切特性受到的物理影响。结果表明:混凝土表明粗糙度对试验结果产生直接影响,并且随着粗糙度的增大,界面抗剪强度、界面摩擦角、剪切刚度系数以及界面残余剪切应力均相应增大,最大增幅可达37.0;而界面附着力随粗糙度的增大呈先减小后增大的趋势,增大幅度达23.7%。随着黏性土含水率的增大,界面抗剪强度、剪切刚度系数和界面残余剪切应力均呈先增大后减小趋势,含水率在20%~28%之间存在一个最优含水率使得界面抗剪特性最优;粉质黏土-混凝土界面的抗剪强度受粗糙度和含水率的影响较大。试验结果可为静压桩的工程实践提供借鉴与参考。

关键词：粉质黏土-混凝土粗糙度含水率抗剪强度特性

多种能场高性能加工复杂曲面关键技术研究进展

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机械工程学报 2024年第9期60卷 152-167页

作者：吴淑晶王大中谷顾全黄帅董国军郭国强安庆龙李长河上海工程技术大学机械与汽车工程学院上海201620 哈尔滨工业大学机电工程学院哈尔滨150001 上海航天精密机械研究所上海201600 上海交通大学机械与动力工程学院上海200240 青岛理工大学机械与汽车工程学院青岛266520

综述多能场高性能加工复杂曲面关键技术的最新进展,展示该领域研究成果中的关键科学与技术问题。首先,系统分析了超声振动辅助加工技术、激光加工技术和电火花加工技术等高能场在复杂曲面加工中的应用形式与工艺特点。其次,揭示了电解... 详细信息

综述多能场高性能加工复杂曲面关键技术的最新进展,展示该领域研究成果中的关键科学与技术问题。首先,系统分析了超声振动辅助加工技术、激光加工技术和电火花加工技术等高能场在复杂曲面加工中的应用形式与工艺特点。其次,揭示了电解加工技术、微量润滑绿色辅助加工技术和磁力辅助研磨加工技术等非高能场加工技术对复杂曲面加工效率与表面质量的影响机制。同时,将多个能场的优势相结合,突破多能场应用的关键技术,改善复杂曲面的加工效果。系统分析了多能场复合加工技术中低能场与低能场、高能场与低能场耦合的技术发展现状。最后,分析多能场复合加工技术中能场叠加带来的技术局限性,并对该技术领域未来的发展态势进行展望,为多能场高性能加工复杂曲面的工程应用提供参考。

关键词：多场复合加工复杂曲面薄壁件超声振动加工微量润滑技术电化学加工激光加工

Al_(2)O_(3)/SiO_(2)混合纳米流体微量润滑铣削润滑性能评价

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制造技术与机床 2024年第10期 29-34页

作者：柏秀芳董兰宋宇翔胡树国李长河青岛理工大学机械与汽车工程学院山东青岛266520 青岛滨海学院机电工程学院山东青岛266555

由于不同纳米粒子组成的混合纳米流体比单一纳米粒子切削液具有更好的热物理性能,研究了纯Al_(2)O_(3)、纯SiO_(2)和不同质量比混合纳米流体微量润滑(minimum quantity lubrication,MQL)铣削45号钢的切削性能。试验结果表明,混合纳米流... 详细信息

由于不同纳米粒子组成的混合纳米流体比单一纳米粒子切削液具有更好的热物理性能,研究了纯Al_(2)O_(3)、纯SiO_(2)和不同质量比混合纳米流体微量润滑(minimum quantity lubrication,MQL)铣削45号钢的切削性能。试验结果表明,混合纳米流体比纯SiO_(2)铣削力降低,接触角减小,工件微观形貌好。不同配比的混合纳米粒子展现出了不同的润滑效果。当Al_(2)O_(3)的配比小于SiO_(2)时,Al_(2)O_(3)纳米粒子未完全包覆住SiO_(2),润滑效果较差。随着Al_(2)O_(3)比例增加,切削力和接触角都显著减小,工件表面质量提高。当Al_(2)O_(3)和SiO_(2)的质量比为3∶1时,得到的铣削力、表面粗糙度和接触角最小,工件表面质量最好。由此可见,Al_(2)O_(3)的含量影响了混合纳米流体的润滑效果。

关键词：铣削微量润滑混合纳米流体润滑性能 Al_(2)O_(3)纳米粒子