基于结构光的焊缝图像采集软件开发研究

实现焊缝跟踪对于保证焊接质量和提高焊接效率具有重要的意义.文中简述了结构光焊缝跟踪系统的硬件构成及其原理.基于系统硬件构成,采用多线程技术,利用Delphi 7.0开发系统软件,给出了软件各模块实现的流程图.重点阐述了图像采集的实现步骤,其主要包括图像采集卡的初始化、图像采集及其显示和图像目标截取.在实现过程中采用了双缓冲、多线程等关键技术,保证了系统的实时性和可靠性.试验结果表明,焊缝图像采集高速有效,图像显示清晰,完全满足焊缝跟踪的性能要求.     

轴承试验机测控系统的开发

针对轴承试验机的工艺要求,设计了轴承性能测试系统.该系统主要包括轴承旋转运动控制、轴向油缸的加载控制、径向油缸的加载控制等模块.测控系统采用工业计算机作为硬件平台,采用多功能数据采集卡采集轴承在拉压力作用下的扭矩、位移、载荷、转速、转角、温度等性能参数.这些参数为改进轴承设计提供了依据.     

基于冲击脉冲法的齿轮箱轴承故障诊断

齿轮箱作为机械设备中的关键部件,其安全服役性能评估及寿命预测环节是非常重要的。因此,设计了一套基于冲击脉冲法的齿轮箱轴承故障检测系统。探究了检测系统的设计原理,并进行硬件选型(如NI四通道数据采集卡、加速度传感器等)、软件模块设计(如数据采集模块、分析和处理模块等)。根据车间现场条件制定齿轮箱轴承跑合检测试验方案,分别测试了不同返修级别(4级修、5级修)的齿轮箱轴承。对检测结果进行分析,表明:所设计的齿轮箱轴承检测系统能够实现对不同返修级别的齿轮箱轴承系统进行故障状态甄别,具有较高的稳定性,可为初步判定不同返修级别的齿轮箱轴承中磨损程度或故障状态提供数据支撑。     

小型牙刷植毛机数控系统的模块化设计

论文着重论述了植毛机电气控制系统的主要硬件模块：单片机控制模块、键盘输入模块、LCD显示模块、PLC控制模块、伺服控制模块及其软件模块。植毛机采用闭环控制方式及逐点比较法的插补控制算法,能快速、准确的完成植毛动作。实际应用表明,该系统具有良好的稳定性。     

基于PLC和触摸屏技术的压铸模型芯针冷却控制系统

压铸模细小型芯针的工作温度是压铸模温度控制中的一大难点.针对压铸件小尺寸孔洞成形质量差,型芯针容易变形、粘模、断裂等问题,开发了基于PLC和触摸屏技术的型芯针冷却控制系统.本系统采用高压冷却水结合吹压缩空气的冷却方法控制型芯针的温度,且冷却水独立封闭循环使用.系统硬件设计采用了“PLC+触摸屏”控制方案,以PLC作为上位机,结合嵌入式触摸屏和A/D转换模块组成整个系统的核心;系统软件设计应用触摸屏组态界面并结合PLC控制程序.生产应用表明,采用本系统后,型芯针温度波动小,使用寿命大幅延长;铸件质量提高,废品率降至2％以下.同时系统界面直观、简洁;参数输入、查询显示方便;控制动作稳定可靠.     

无线传感与LabVIEW结合的轴承运行状况监测系统

针对现有轴承故障诊断系统中有线信号采集存在布线困难、部署成本高、可维护性差和监测范围有限等问题,设计一种可实现轴承振动信号无线采集的模块。该模块采用压电式加速度传感器采集轴承振动信号,以STM32F103RET6为主控芯片,利用ADS8344和DAC8531进行AD/DA转换,通过蓝牙技术进行无线传输。最后使用DAQ数据采集卡以及以LabVIEW为开发平台的虚拟仪器,在线监测轴承的运行状况,为轴承故障诊断提供了一种新思路。     

基于空间电荷采集实现电子束焊接过程实时监控的装置及方法

为了实现电子束焊接过程的在线监控,保证焊缝成形质量,研制了一套空间电荷信号采集处理系统,系统由传感采集模块、信号处理模块和显示分析模块组成.通过多组6061铝合金平板对接焊接工艺试验,实时采集焊缝熔池正上方8个位置的电荷,分析电荷信号波形特征与焊接成形质量关系规律,建立了波形变化对焊缝成形质量判据准则.结果表明,该系统采集的信号波形能够有效的评价焊接过程稳定性,以及实时判断焊偏、未熔合、焊穿等成形缺陷.     

基于MATLAB GUI的谐波减速器专用柔性深沟球轴承设计及接触分析系统

为缩短轴承设计、分析、计算周期,提高轴承设计效率和精度,将谐波减速器专用柔性球轴承作为研究对象,采用MATLAB GUI软件平台开发谐波减速器专用柔性球轴承设计及参数修正模块、轴承设计参数检测模块、接触应力计算模块和ABAQUS有限元联合分析计算模块。所设计的分析系统使用方便,只需输入轴承主参数,便可完成轴承参数设计、最大接触应力计算、有限元分析,且结果可在系统界面显示或以txt、Excel文件形式输出。介绍谐波减速器专用柔性球轴承设计方法,对已完成设计的轴承参数进行验证及分析,并进行多次工程应用。结果表明：该系统高效可靠。     

低温风洞不锈钢洞体焊接关键参数监测与分析系统

为控制低温风洞不锈钢洞体的焊接质量,研制了一套焊接关键参数监测与分析系统.以传感器、PLC控制器以及无线收发射模块为基础,分别构建了系统硬件的感知层、控制层以及设备层,并设计了电源系统,开发了上位机与下位机软件,实现对电流、电压以及焊接线能量等焊接参数的采集、分析及处理.根据实际需要,制定了数据筛选规则、数据存储与显示...     

超声波特征扫描成像系统的研制及应用

介绍了超声波特征扫描成像系统的研制,包括硬件和软件功能的设计及实现。系统硬件部分包含脉冲发射/接收器、高速同步数据采集模块、多轴运动平台和探头的夹持装置等;软件设计基于VC2008平台,包含数据采集、图像显示、运动控制、数据存储等功能模块。采用该系统对铁路钢轨轨头进行超声波扫描成像试验,给铁路钢轨在线超声波探伤提供技术支撑。     

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.     

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.