基于工业机器人的不锈钢抽油烟机自适应打磨系统的开发

结合人工打磨不锈钢抽油烟机的现场操作,研究不锈钢打磨的要点,将工业机器人技术、比例阀控制技术、力反馈技术、PLC控制技术等结合在一起,利用气动执行元件,通过Solid Works软件进行结构设计,完成了一种基于机器人的自适应不锈钢抽油烟机打磨系统的开发。安装在刚性很强的机器人上的打磨头能在工件表面始终保持恒定的打磨压力,保证了工件的打磨品质。设备实现了打磨的智能化、自动化,不仅可以应用于不锈钢抽油机产品,还易于推广到陶瓷等其它产品表面的打磨,对于提高劳动生产率、提高难于打磨产品的质量具有重大应用价值。     

打磨机器人控制系统设计与研究

为解决卫生陶瓷行业中的干胚打磨粉尘浓度高,噪声大,工作环境比较恶劣,影响工人的身体健康的问题,设计并开发了一套基于6轴工业机器人的自动打磨系统。通过设计机器人末端的力控法兰打磨机构,基于Labview开发了打磨机器人末端力控法兰的上位机软件,与工业机器人通讯,运用PID控制系统,进行恒力打磨实验,结果表明:打磨机器人可以控制输出相对平稳的接触力,验证了力控法兰设计的可行性,满足了卫生陶瓷打磨对接触力控制的需求。     

汽车顶盖激光焊缝打磨系统的设计与应用

针对汽车顶盖激光填丝钎焊的焊缝表面存在鱼鳞纹、锯齿边等缺陷，提出一种基于自适应接触法兰、电主轴和机器人的打磨系统。通过固定在机器人末端的自适应接触法兰使打磨片以恒定压力压紧焊缝，电主轴带动打磨片高速旋转，高速旋转的打磨片磨削焊缝。介绍了该系统的硬件组成、通信架构以及打磨流程，并分析了接触法兰压力、电主轴旋转方向及转速和打磨姿势对打磨品质的影响规律。     

基于神经网络的打磨机器人的力/位混合控制

针对封头打磨机器人在工作过程中末端执行器轨迹跟踪和恒力控制要求与打磨机器人在封头上行走的振动抑制问题,提出一种基于神经网络的力/位混合控制方法。采用力/位混合控制器完成打磨机器人力和位置的同时控制要求。针对打磨机器人平台行走过程产生的振动干扰,设计神经网络鲁棒控制器,通过神经网络对系统参数误差和振动干扰进行抑制。仿真结果显示,该混合控制器不仅能保证打磨机器人末端执行器位置的精确控制和有效的恒力控制,而且对外界振动干扰有很好的抑制效果。     

轨道车辆转向架横梁非常规焊缝自动打磨系统及工艺研究

针对人工打磨轨道车辆转向架构架横梁非常规焊缝存在劳动强度大、质量低等问题,设计了一种轨道车辆转向架构架横梁非常规焊缝自动打磨系统,使用恒力控制装置(AFD)以控制打磨压力,使用激光扫描模块以确定焊缝的位置、高度等必要的打磨工艺信息,设计新的打磨刀具以便于机器人能够更好地对燕尾区及环形焊缝实施打磨作业,根据转向架构架横梁非常规焊缝的特点制定合理的打磨工艺。通过打磨实验,证明了所设计的轨道车辆转向架构架横梁非常规焊缝自动打磨系统的优越性以及打磨工艺的合理性。     

汽车水冷机壳铸件机器人打磨工作站设计

汽车电机水冷机壳完成低压铸造后，人工打磨铸件时劳动强度大、打磨工艺成本高、精度差且效率低。设计了一套机器人打磨工作站系统，包含水冷机壳旋转台夹具、IRB2600机器人、双浮动电主轴、护栏4大部件。利用机器人离线仿真软件RobotStudio进行了机器人打磨工作站的布局、动作模拟、打磨路径以及周期节拍的仿真。在实际构建机器人系统之前，先进行了水冷机壳打磨工艺过程中机壳的姿态位置、旋转角度、停顿时间和双浮动主轴的粗、精打磨工艺换刀的设计和试运行，并进一步优化打磨路径及细节来获得更高的打磨质量，为水冷机壳铸件机器人打磨提供真实的验证。该打磨工作站不但可提高去铸造毛刺的效率，也可以实现机器人打磨工作站的连贯性，进而提高电机水冷机壳行业机壳打磨的自动化水平。     

双臂机器人的轨迹跟踪控制方法研究

针对工件在实际加工中打磨空间局限、精度不高等问题,为提高机器人作业的轨迹跟踪效果,提出一种双臂机器人轨迹跟踪控制方法。以轮毂打磨为研究背景,主从架构中夹持机器人采用PD控制,夹持待打磨工件进行位置跟踪运动控制;打磨机器人采用基于位置的阻抗控制,实现力控和末端位置补偿,提高定位精度。基于MATLAB/Simulink设计仿真模型验证可行性,并完成实验验证。实验结果表明：当机器人末端在外界干扰力作用下,能自适应地跟踪及修正轨迹,满足双臂机器人轨迹跟踪控制的要求。     

机器人在零件清理打磨中的应用及发展趋势

许多金属零件存在飞边、毛刺,需要在成形后进行清理打磨。通过介绍飞边清理和去毛刺的常用方法以及机器人在清理打磨行业的应用现状,分析了清理打磨机器人的关键技术要求,并展望了其发展趋势。     

机器人在三缸曲轴打磨工艺中的应用研究

为了对三缸曲轴进行自动、快速、精确的打磨,设计了一套采用多台机器人协作的打磨单元。对三缸曲轴铸件及其披缝的外形特征进行分析,在此基础上,设计了磨具形式、机器人应用方式和曲轴装夹方式,并进行了详细介绍。在打磨过程控制方面,提出了利用磨削电主轴的电流实时控制机器人的打磨进给速度的方法,提高了系统的安全性。此系统已投入使用,实现了对三缸曲轴安全、可靠、精确、高效的自动打磨     

打磨抛光机器人控制系统设计与开发

为了解决传统手工打磨效率和打磨精度低等问题,文章采用PLC控制打磨机器人,实现对复杂曲面的打磨抛光,并基于Qt软件设计了人机交互界面,实现了机器人打磨系统的状态控制和监控。该控制系统可以实现复杂曲面的全自动化打磨抛光过程,并且可以实时监控设备运行参数,操作简单灵活,易于维护。对不锈钢回转体的打磨抛光实验结果表明:打磨抛光时间为2.5min,自动全流程时间为3 min,较人工打磨方式效率提高了60%。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.