触摸屏自动贴合设备开发

针对触摸屏贴合工艺制程中多层复杂结构且较难实现特定标记的对位,开发出自动化影像伺服贴合生产设备。采用无标记影像对位技术,以区域影像拾取搭配归一化互相关算法的影像搜寻技术,实现自动搜寻与定位坐标拾取;以异空间取像设计影像自动对位系统,通过补偿控制参数最佳化后,能有效降低对位次数。测试结果表明:该设备能够实现多层组件的自动化精密对位贴合,贴合精度在100μm以内,生产良率达95%以上,符合行业生产规范要求。     

微波滤波器自动调谐装备的研制北大核心

针对目前普遍采用人工调节调试螺杆实现微波滤波器的谐振频率调节,其存在产品一致性差、生产效率低、人力成本高等不足,提出了微波滤波器自动化调谐工艺,研制出了适应多种不同规格调试螺杆和盖板的微波滤波器自动调谐装备。装备采用直角坐标的移动夹具,集自动上下料、自动组装、自动调谐等功能于一体,通用性好。采用工控机和液晶显示器作为人机交互装置,以固高运动控制卡为控制系统核心,最大化地满足高阶复杂的控制要求。所设计的微波滤波器自动调谐装备在实际运用中表现高效稳定,调谐效果好,具有良好的市场前景,为调谐自动化奠定了基础。     

南非21E构架侧梁下盖板组成焊接工艺

阐述了南非21E构架侧梁下盖板组成的特点及焊接工艺难点、要点,着重分析了南非21E构架侧梁下盖板组成结构特点、工艺特点、工艺装备设计、焊接过程控制等对下盖板组成焊接变形及焊接质量的影响,并通过焊缝外观检验、焊缝射线探伤检验、焊缝宏观金相试验及侧梁下盖板组成外观尺寸检验对南非21E构架侧梁下盖板组成焊接工艺进行了验证。     

薄壁曲面零件的锻造成形工艺

某产品上用的一重要零件为薄壁曲面类零件,实际生产中主要采用机械加工制作,工序多,时间长,并浪费原材料.本文采用锻造成形工艺,锻模设计为曲面分模面模具结构,实现了薄壁曲面零件的锻造成形.零件成形后,无需再进行后续机械加工,产品的尺寸和形状均可直接达到使用要求.经过工艺试验和小批量的试生产考核,其尺寸和形状均能满足图纸技术要求,并且产品尺寸和形状的一致性好.与机械加工工艺相比,锻造成形工艺大幅度提高了产品生产效率和材料利用率,极大降低了生产成本.     

基于神经网络的铸造模具曲面逆向工程造型

研究目的是通过神经网络方法反求铸造模具复杂曲面.利用径向基函数(RBF)神经网络优异的非线性逼近能力,将外形数据、加工余量、变形数据作为神经网络输入,在神经网络的输出上可以得到铸造模具曲面离散数据点.再通过输出数据,可以对模具曲面进行造型.模具曲面的重构精度高、速度快.通过在复杂曲面模具造型上的实际应用,证明该方法能够实现产品和工艺装备的并行设计,可以缩短产品研制周期,提高设计、生产速度和效率,具有实用推广价值.     

大型工程机械驾驶室机器人自适应打磨抛光系统的设计

为适应当前制造业大型设备零部件生产需要,提高对大型工程机械驾驶室焊缝打磨抛光处理效率,设计一种机器人自适应自动打磨系统。此系统采用六自由度机器人配置自适应性力控系统,实现对复杂曲面及焊缝的贴合;采用外接轴实现对工件所有焊缝全方位覆盖,并实时切换姿态完成自动打磨。通过自动更换打磨工具的方式,实现单个机器人生产效率最大化;运用模块分层化理念,使不同工位满足不同工艺需求,凸显此系统良好的兼容性;其中加装的自适应性力控装置,实现了工业参数数据化,其可调可控,从而保证打磨抛光的效果。挖掘机驾驶室焊缝打磨抛光试验结果表明：此系统可实现对大型工程机械驾驶室焊缝打磨抛光全自动化处理,且保证了打磨效果,可以满足生产要求。     

粗丝CO2气体保护焊在起重机主梁制造中的工艺试验及其应用

本文提出对起重机主梁盖板的对接、盖板与腹板的角接,采用粗丝 CO_2气体保护自动焊的先进工艺,通过工艺试验和焊接质量检验,获得了符合产品技术要求的优质焊接接头。     

中国焊接生产机械化自动化技术发展回顾

中国焊接生产机械化、自动化技术发展的应用经历了仿制、自行研制和稳步发展三个阶段。本文从自动化焊接装备技术、焊接自动控制技术,焊接生产线机构化与自动化技术等方面,对中国焊接生产机械化、自动化技术发展历程进行了回顾。     

便携式计算机电池保护器双面自动贴合机的研究与设计

针对便携式计算机电池保护器生产过程中存在的自动化程度低、麦拉片贴合良品率低等问题,设计了便携式计算机电池保护器双面自动贴合机及其控制系统。通过对便携式计算机电池保护器双面自动贴合机工艺要求及功能特点分析,确定设备整体设计方案,并对其关键部件进行了详细设计,包括麦拉片传送机构、麦拉片贴合机构等;采用PLC作为控制系统的主控制器,实现电池保护器双面自动贴合麦拉片;以触摸屏作为人机交互界面,实现设备调试及系统运行状态监测等功能。该设备已投入实际生产使用,应用效果表明:该设备运行稳定,操作简单,自动化程度高,提高了产品生产效率和良品率。     

洗衣机上盖板注射模设计

洗衣机上盖板属于透明曲面板类塑件,分析了该塑件的结构特点,设计了一幅双分型面注射模,并介绍了该模具的工作过程。实践证明所设计模具结构合理,操作方便,生产效率高。     

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.     

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.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

电化学噪声数据处理方法概述

综述了常见的电化学噪声数据处理方法,介绍了直流趋势剔除、统计分析、快速傅立叶变换(FFT)法计算功率谱密度(PSD)以及小波变换处理电化学噪声信号的基本过程,并阐释了各种数学处理及所得参数的物理意义。