检索结果-内蒙古大学图书馆

Study on high temperature plasticity of Q390 microalloyed steel

Journal of Physics: Conference Series 2021年第1期2044卷

作者： Bo Xu Liejun Li Wang Zheng Guang Wang Jixiang Gao Guangdong key Laboratory for Processing and Forming of Advanced Metallic Materials South China University of Technology Guangzhou 510640 China. Wuhan University of Science and Technology Wuhan 430081 China. SGIS Songshan Co. Ltd Shaoguan 512123 China. Guangdong Polytechnic Normal University Guangzhou 510635 China.

In this paper, the effect of Al and Ti on the high temperature plasticity of Q390 microalloyed steel was studied. The high temperature tensile tests of two Q390 steels with different contents of aluminum and titanium (0.02%Al-0.01%Ti and 0%Al-0.02%Ti) were carried out on Gleeble 3800 thermal simulation test machine. The high temperature plasticity of the two steels was compared and analyzed by calculation of shrinkage ratio, fracture morphology and energy spectrum of the precipitates. The study indicated: The toughness of 0%Al-0.02%Ti steel is 12%-35% higher than that of 0.02%al-0.01%Ti steel in the III brittleness temperature zone. Aluminum has a negative effect on the high temperature plasticity of microalloyed steel, while titanium has a positive effect on the high temperature plasticity of microalloyed steel. Therefore, the surface quality of Q390 microalloyed steel is improved when Q390 is adopted the composition of 0%Al-0.02%Ti steel.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Design of a New Engine Hood based on Lattice Structure for Pedestrian Protection

引用

Journal of Physics: Conference Series 2021年第1期1965卷

作者： Meng Liu Fuzhen Sun Baoming Wang Jianfeng Wang Na Yang State Key Laboratory of Advanced Forming Technology and Equipment Beijing 100044 P. R. China The University of Science and Technology Beijing 100083 P.R. China Weihai Guangwei Group Corporation Weihai 264200 P.R. China School of Automotive Engineering Harbin Institute of Technology Weihai 264209 P.R. China

This paper designs four kinds of three-dimensional negative Poisson's ratio lattice structures, based on the two-dimensional concave hexagonal negative Poisson's ratio honeycomb structure. Different parameters are designed for simulation analysis and experimental research, and the influence of different parameters on Poisson's ratio is studied respectively. The main contents are as follows: Firstly, the three-dimensional solid model of lattice structure is established by modeling software, and the different structural parameters are determined, and the equivalent mechanical model is established. And according to the relevant structural parameters to establish the test scheme. Then, the finite element software is used to simulate the test core material with different parameters. According to the simulation results, the influence of different parameters on Poisson's ratio is found out. Then the crashworthiness of the test board with different parameters is simulated and analyzed. According to the results, the most suitable structure is selected and applied to the engine hood. Finally, the simulation experiment of collision between pedestrian head and engine hood is carried out. The results of this paper compare the performance of lattice sandwich panels with different parameter structures in different tests and select the optimal combination of structural parameters. The adjustment and optimization direction of the structure is put forward according to the test results.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Study on Automobile Front-End Structure Based on Pedestrian Leg Protection

引用

Journal of Physics: Conference Series 2021年第1期1965卷

作者： Meng Liu Fuzhen Sun Baoming Wang Jianfeng Wang Na Yang State Key Laboratory of Advanced Forming Technology and Equipment Beijing 100044 P.R. China The University of Science and Technology Beijing 100083 P.R. China Weihai Guangwei Group Corporation Weihai 264200 P.R. China School of Automotive Engineering Harbin Institute of Technology Weihai 264209 P.R. China

According to the pedestrian leg protection regulations, a collision with the simplified finite element model of the leg was carried out on the basis of incorporating EPP foam materials with different foaming rates and cushioning into the simplified front-end structure of the car. The results show that the front-end foam energy-absorbing structure of the vehicle cannot meet the pedestrian leg protection regulations. This paper designs a thin-walled steel structure and applies it to the front-end structure of the vehicle. After collision simulation with a simplified finite element model of the leg, the pedestrian's tibial acceleration, knee joint shear displacement and knee joint bending angle are compared and analyzed. Pedestrian leg injury parameters, the results show that thin-walled steel structure is more suitable for giving full play to the energy absorption effect in an environment with insufficient energy absorption space than foam energy absorption structure.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Microstructure and mechanical properties of Mg-5Li-1Al sheets prepared by accumulative roll bonding

引用

Journal of Materials Science & technology 2018年第2期34卷 317-323页

作者： Legan Hou Tianzi Wang Ruizhi Wu Jinghuai Zhang Milin Zhang Anping Dong Baode Sun Sergey Betsofen Boris Krit Key Laboratory of superlight Materials &Surface Technology Ministry of Education Harbin Engineering University Harbin 150001 China Suzhou Changfeng Avionics Co. LTD. Suzhou 215151 China Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming Shanghai Jiao Tong University. Shanghai 200240 China Moscow Aviation Institute National Research University Moscow 109383 Russia

Ultrafine-grain and high-strength Mg-SLi-1Al sheets were prepared by accumulative roll bonding （ARB） process. Evolution of microstructure and mechanical properties of ARB-processed Mg-5Li-1Al sheets was investigated. Results show that, during ARB process, the evolution of deformation mechanism oft Mg-5Li-1Al alloy is as follows： twinning deformation, shear deformation, forming macro shear zone, and finally dynamic recrystallization （DRX）. The grain refining mechanism changes from twin DRX to rotation DRX. With the increase in ARB cycles, strength of the Mg-5Li-1Al sheets is enhanced, whilst elongation varies slightly. With the increase in rolling cycles, anisotropy of mechanical properties decreases. It is conclusive that strain hardening and grain refinement dominate the strengthening mechanism of Mg-5Li-1Al alloy.

关键词： Mg-Li alloy Accumulative roll bonding Microstructure Mechanical property

来源：评论

学校读者我要写书评

暂无评论

Analysis on performance and test of a new type of ultra-high pressure pipe joint

引用

High technology Letters 2018年第2期24卷 203-207页

作者： Zhai Fugang Kong Xiangdong Sun Yugang Wang Zhong Hao Xiaobei College of Mechanical Engineering Yanshan University Qinhuangdao 066004 P. R. Chin Key Laboratory of Advanced Forging ＆ Stamping Technology and Science （Yanshan University） Ministry of Education of China Qinhuangdao 066004 P. R. Chin Huaye Power Technology Co. Foshan 528300 P. R. China

Analysis as well as application of ultra-high pressure hydraulic system and elements has become a trend. The structure and operation principle of a new type of ultra-high pressure pipe joint is introduced. The structure of the new type of ultra-high pressure pipe joint is simple and is easy to be produced. The finite element model on two working conditions( preload condition with 30 N·m torque and static-loading condition with 70 MPa pressure) is built and computed. The width of contact area,the equivalent stress status,as well as the contact pressure status are plotted and analyzed. According to the national standard,test on air-tightness,blasting,and cyclic endurance is conducted and the results show that the new type of ultra-high pressure pipe joint has the sealability for ultra-high pressure up to 70 MPa,and the DN6 ultra-high pressure pipe joint can provide effective seal under70 MPa fluid pressure. The research can provide a thinking and method on designing ultra-high pressure pipe joint and push forward the development of ultra-high pressure hydraulic system.

关键词： pipe joint ultra-high pressure sealing performance hydraulic system

来源：评论

学校读者我要写书评

暂无评论

Method for near-net forming of a sand mold with digital flexible extrusion technology

引用

China Foundry 2017年第6期14卷 492-497页

作者： Shuai Zhang Zhong-de Shan Jing-wei Ji Zhao-xian Gu State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Beijing 100044 China

In order to further improve the precision forming efficiency of a sand mold digital patternless casting and reduce the amount of sand mold cutting, a method for near-net forming of the sand mold with digital flexible extrusion technology was put forward. The theory, optimization algorithm and technology for sand mold nearnet forming were studied. Experimental results show that the sand mold forming efficiency can be increased by 34%, and the molding sand can be reduced by 44%. The method for near-net forming of a sand mold with digital flexible extrusion technology can effectively promote the application of digital patternless casting technology in the mass production of castings and thus greatly improves the efficiency and automation of sand mold manufacturing.

关键词： patternless casting technology near-net forming sand mold flexible extrusion technology geometric packing

来源：评论

学校读者我要写书评

暂无评论

Model-based Synchronous Control of Redundantly Actuated Parallel Manipulator with Neural Network

引用

Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery 2018年第2期49卷 367-375页

作者： Liu, Xiaofei Yao, Jiantao Zhao, Yongsheng Key Laboratory of Advanced Forging and Stamping Technology and Science Ministry of Education Yanshan University Qinhuangdao066004 China Key Laboratory of Parallel Robot and Mechatronic System of Hebei Province Yanshan University Qinhuangdao066004 China

Redundantly actuated parallel manipulator demands higher actuation coordination than the non-redundantly actuated one, thanks to its degree of actuation exceeding its degree of freedom. To improve the actuation coordination of redundantly actuated parallel manipulator, a novel model-based driving force synchronous control method with neural network was proposed. With 6PUS+UPU parallel manipulator as object, dynamic model was derived based on virtual work principle. To improve the actuation coordination of redundantly actuated parallel manipulator, a novel driving force synchronous control method was proposed on basis of force-position hybrid actuation. The synchronous control method was based on the driving force error of actuated joints and driving force adjustment was calculated by the synchronous controller. The synchronous controller was designed with neural network. What's more, the learning law of neural network controller was derived with manipulator's dynamic model to improve the learning efficiency. Model simulation and prototype experiment were carried out, and a performance comparison analysis with traditional force-position hybrid actuation method was made to verify the proposed control method. Comparison analysis revealed that, comparing with the traditional force-position hybrid actuation method, driving force synchronous control with neural network proposed could effectively improve the actuation coordination of redundantly actuated parallel manipulator. The results revealed that the synchronous control method reduced the driving force errors of whole manipulator by properly magnifying the control error of force actuated joint. © 2018, Chinese Society of Agricultural Machinery. All right reserved.

关键词： Dynamic models

来源：评论

学校读者我要写书评

暂无评论

Driving force synchronous control of redundantly actuated parallel manipulator

引用

Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS 2018年第9期24卷 2140-2149页

To improve the actuation coordination of redundantly actuated parallel manipulator, a novel model-based driving force synchronous control method was proposed. With 6PUS+UPU parallel manipulator as the research object, the dynamics model was deduced based on virtual work principle, and the coordination mechanism of driving force under scheduled motion was analyzed. On the basis of force-position hybrid actuation, a driving force synchronous control method was proposed, and the control algorithm was designed with coordination mechanism. Simulation and prototype experiment were used to verify the proposed control method. © 2018, Editorial Department of CIMS. All right reserved.

关键词： Manipulators

来源：评论

学校读者我要写书评

暂无评论

开式泵控非对称缸负载容腔独立控制系统（英文）

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第3期19卷 203-210页

作者： Jing YAO Pei WANG Xiao-ming CAO Zhuo WANG The Laboratory of Heavy Machinery Fluid Power Transmission and Control in Hebei Yanshan University Qinhuangdao 066004 China National and Local Joint Engineering Center for Advanced Forging Press Forming Technology and Equipment Faculty of Engineering Yanshan University Qinhuangdao 066004 China Yanshan University Qinhuangdao 066004 China

目的:为减少能量排放和提升节能效果,并解决非对称缸系统的流量不对称问题,本文对开式泵控非对称缸负载容腔独立控制系统的控制特性及能耗特性进行了深入的研究,以期为其实际应用提供理论支撑。创新点:1.提出开式泵控非对称缸负载容腔... 详细信息

目的:为减少能量排放和提升节能效果,并解决非对称缸系统的流量不对称问题,本文对开式泵控非对称缸负载容腔独立控制系统的控制特性及能耗特性进行了深入的研究,以期为其实际应用提供理论支撑。创新点:1.提出开式泵控非对称缸负载容腔独立控制系统,建立其能量传输模型;2.以压机为对象进行实验研究,采用位置压力负载容腔独立控制方法,获得其能耗与控制特性。方法:1.介绍开式泵控非对称缸负载容腔独立控制系统的构型;2.通过理论推导,建立能量传输模型,得到具有能量回收功能的系统;3.通过实验研究和分析,验证所提系统和方法的有效性。结论:1.基于能量传输模型得到的系统具有较好的节能特性;2.开式泵控非对称缸负载容腔独立控制系统增加了系统控制自由度,验证了负载容腔独立控制方法的有效性;3.开式泵控非对称缸负载容腔独立控制系统采用无杆腔位置控制和有杆腔压力控制组合的控制方法;随着有杆腔压力的提高,在不增加系统能耗的前提下该方法改善了系统的位置控制精度。

关键词：泵控系统非对称缸能耗位置压力组合控制负载容腔独立控制

来源：评论

学校读者我要写书评

暂无评论

Heat treatment and granule medium internal highpressure forming of AA6061 tube

引用

Journal of Central South University 2017年第5期24卷 1040-1049页

作者： BI Jiang ZHAO Chang-cai BI Meng-meng DU Bing CHEN Xiao-hua DONG Guo-jiang Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China College of Vehicles and Energy Yanshan UniversityQinhuangdao 066004China

The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy.

关键词： aluminum alloy tube solution treatment aging treatment granule medium internal high pressure forming

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：