一种识别薄板对接接头的视觉方法

对薄板紧密对接接头的识别问题进行了深入的分析，提出了由照明、自适应局部特征提取、全局特征识别和验证融合在一起的视觉识别方法。它克服了电弧光的干扰，识别结果可靠，可以有效地解决薄板紧密对接接头识别这一难题。     

基于Moldflow的汽车操纵杆注塑成型质量分析与优化

采取Moldflow分析并优化了汽车操纵杆注塑成型的质量。结果表明:在设计的三种浇注系统方案中,方案1通过增加浇口数量,采用两个点浇口进胶,熔接线、短射、翘曲变形最严重;方案2对注塑位置进行调整,有效改善了翘曲变形的情况,但熔接线、短射现象较明显;方案3熔接线变淡,但有效改善了短射和翘曲变形的情况。在模具温度61℃、熔体温度178℃、保压压力为91%填充压力、注射时间5.6 s、保压时间11 s条件下,翘曲具有最小变形量。试模实验表明:操纵杆饱满性较强,填满了卡铜线的四个凸台,并未出现侧边卡位缺胶的情况,熔接线也没有呈现在内外表面上,样品翘曲变形值为1.632 mm,最佳因素水平组合的Moldflow模拟的翘曲变形量为1.617 mm。     

满足多种供电输入的大功率电源设计

基于大功率设备供电设计了一款效率高、功率密度大的供电单元;可以采用单相220 V供电,也可以采用三相四线380 V供电,给大功率设备功放单元提供了高达2400 W的输出,同时配备了三路独立的24 V输出;通过芯片C8051F330能实现与上位机串口通信,能控制电源的启动以及监测各路直流输出的电压、电流大小和整机的温度,对末级功放单元的供电可以实现阶梯式八级电压的调整;能自动识别交流输入的欠压、过压,可以有效的保护整机电源不受损伤;具有输入过欠压保护,输出过压保护、输出过流保护、输出短路保护和过温保护等功能.     

Friction stir welding of AZ31 magnesium alloy

Friction stir welding (FSW) is an new solid-phase joining technology which has more advantages over fusion welding methods in welding of aluminum and other non-ferrous metals. The effects of welding parameters on mechanical properties and microstructure during friction stir welding of AZ31 magnesium alloy were studied in this paper. Microstructures and mechanical properties of the joints were investigated by means of optical microscopy, scanning electric microscopy ( SEM ) , micro-hardness analysis, and tensile test. Experimental results show that the magnesium alloy can be successfully welded by FSW method, and the ultimate tensile strength (UTS) of FSW joint reaches up to 90 percent of base metal. The microstructures of welded joints exhibit the variation from dynamically recrystallized fine grains to greatly deformed grains. Hardness in nugget zone was found lower than the base metal but not too obvious.     

基于Lab VIEW的熔化极等离子弧焊接电弧电信号分析

在熔化极等离子弧焊接(plasma-MIG)试验系统基础上,设计电流、电压信号采集系统,对其电弧电特性信号进行采集,用虚拟仪器软件LabVIEW对其进行处理,得到U-t,I-t,U-I相图.比较了熔化极等离子弧焊与常规熔化极气体保护焊电弧电信号的不同,前者电流、电压波动很小,后者波动很大;研究了熔化极等离子弧焊接方法中MIG电流增大对电弧电信号的影响,并对熔化极等离子弧焊接的不稳定电弧电信号进行了分析,发现内弧对外弧的影响有一定规律性.     

Numerical simulation of small section rectangular tube in parallel welding

The welding temperature field and deformation of parallel arrangement small-section rectangular tubes is calculated by using a non-contact model. After comparing the computed results with the experimentally measured results, it shows that there exist big errors when applying this model to the numerical simulation of small-section rectangular tube＇ s welding temperature field and deformation. Based on a simple analysis of the errors, a contact model is presented. The heat transfer and stress analysis between small-section rectangular tubes and clamping fixture are simulated by using direct constraints method, and then the laws of the temperature distribution, which coincide with experiment, are obtained. A further numerical analysis of the stress and deformation are made, it shows that a ＂T＂ shaped stress-field is formed in the vicinity of the weld. As the stress-field departs from the centroid of tubes＇, this leads to the small rectangular tubes not only have a longitudinal deflection, but also have a transverse bending and deformation.     

固定点状态下TIG焊接熔深信号的检测及分析--焊接熔深检测的初步探讨

本文采用特殊的恒压焊接电源,建立了一套微计算机控制的实验装置。在TIG 固定点弧焊情况下,通过在正常焊接电流的基础上,每隔一定时间施加一瞬闻激振脉冲电流来激励焊接熔池产生振荡,然后检测电弧电压,以获得激振脉冲过后的焊接熔池振荡信号的方法,对实时测定焊接熔深作了初步探索。在对信号分析的基础上,研究了焊接熔池振荡频率与焊接熔深之间的关系,并建立了相应的数学模型——焊接熔池波动方程。利用有限差分法求解了焊接熔池波动系统的特征值问题,得到了焊接熔池振荡频率与焊接熔深之间关系的数值解.1Cr18Ni9Ti、20~3、16Mn 三种不同材料的实验结果与理论计算结果的吻合程度良好。     

微计算机图象法测示和控制焊接过程的探索

计算机图象法是计算机应用的新发展。本文对微计算机图象法在焊接领域中的应用作了一些探索。研究和配置了不同分辨力的图象输入接口(8BIT、4BIT、二化值),并进行了焊接图象处理、模式识别和反馈自动控制方面的研究。简介了采用微计算机图象法在焊接过程中面积和尺寸形状的测量、焊接温度场测定、焊缝X 光底片判断、焊缝对中等方面的研究工作,从而证明计算机图象法在焊接领域中具有广阔的前途.