电弧超声激发机理的研究

提出以电弧作为可控的“超声发射源”的工作原理，开发了具有一定带宽的激励电源用以激发电弧超声，通过传输线耦合方式与常规弧焊电源进行联机试验。在焊接过程中发现了激发电弧超声的若干谐振频段，记录了电弧超声的频率、幅度和相移。该原理表明，电弧不仅可作为“产热机构”，同时也可作为“超声发射机构”，开拓了电弧在焊接过程自动控制、质量检测等方面应用的新途径。     

活性剂等离子弧焊焊接电弧的特性

针对活性剂等离子弧焊焊接过程,采用红外热像伪着色法测定了活性剂等离子弧焊焊接电弧温度场,并建立了活性剂等离子弧焊焊接电弧热流密度径向分布模型,对焊接电弧外形的变化,焊接电弧电压与活性剂之间的关系进行了研究。研究结果表明：活性剂等离子弧焊焊接电弧的温度分布比较紧凑,温度场外形窄,温度分布范围较集中,电弧径向温度梯度较大。电弧径向温度分布呈现正态Gauss分布模式。活性剂等离子弧焊焊接电弧收缩,弧尾翼消失,尾焰加大,电弧穿透力增强,电弧电压升高。     

焊接材料质量信息的智能化判读

为了在线判读弧焊焊接过程的质量信息,开发了焊接电流、电弧电压信号采集和分析系统.     

焊接电弧监测技术研究现状及展望

对焊接过程中的电弧信息进行实时监测和采集分析,是保证弧焊质量、提升弧焊技术水平的重要途径。随着测量技术和测量方法的不断发展,对焊接电弧复杂信息进行分类提取的手段也逐步发展。文中从电弧热源的物理特性出发,综述今年来国内外开展的电弧焊接过程监视测量的研究现状,主要包括以探针法和纹影法为代表的主动信息采集技术和以电弧电信号、声信号和光信号采集为代表的被动信息采集技术,分类介绍典型焊接电弧监测技术的原理、特点和研究现状,并对该领域的下一步发展趋势进行预测和展望。     

基于电信号与高速摄像的弧焊过程测试分析系统研究

文章针对弧焊过程复杂、非线性的特点,研制了弧焊过程测试分析系统。系统由传感器、数据采集卡、高速摄像机等硬件检测设备、光学设备和控制软件构成。该系统具有电信号采集、瞬时分析、统计分析、同步高速摄影、图像处理等功能。利用该系统对弧焊过程信号进行了测试与分析,实验表明：该系统稳定可靠,功能完善,能有效地对弧焊过程进行监测分析与质量评定。     

分析仪在焊接电参数测试中的应用

采用焊接质量分析系统,对焊接过程电参数进行精确的统计分析,自动生成电弧电压、焊接电流的波形图,电弧电压和焊接电流概率密度分布曲线,以及熔滴短路时间T1、电弧的燃弧时间T2、加权燃弧时间T3和短路周期Tc频数分布图,并且精确地得出相关数据.试验结果表明,汉诺威焊接质量分析系统能够对焊接工艺参数进行评估,为科学评价焊接材料工艺性,提供了新的手段.     

CO2焊机的计算机测试系统的研制

针对当前对CO2焊机电源测试及其焊接过程分析的需要,开发出一套能自动测试弧焊电源性能的系统.通过对焊接过程中电弧电压、电源电流信号进行采集、处理,实现了对电焊机外特性的测试,同时可对焊接工艺性能做出实时评价.该系统具有智能化程度较高、人机界面友好、测试及数据处理功能齐全等特点,为以后焊机工艺技术的提高带来一定的推动作用.     

基于虚拟仪器的弧焊电参数测试仪开发

介绍了一种先进的基于虚拟仪器的弧焊电参数测试仪.以电弧电压和焊接电流为信号源,采用LabVIEW7.1作为软件开发平台,开发了集试验参数设置、数据采集及处理和数据回放及分析三大模块为一体的测试系统.试验结果表明:该弧焊参数虚拟测试分析仪具有良好的灵活性和实用性,人机界面友好.     

电弧光谱信息及其在焊接过程测控上的应用

本文从焊接电弧光谱信息内容及其应用实例两个方面揭示了光谱信息与弧焊过程物理现象之间的本质联系,同时说明光谱诊断法在弧焊过程测控中的意义和应用潜力。对焊接电弧光谱信息的开发利用提供了一些有益的经验。     

基于近似熵的短路过渡焊接规范分析

介绍非线性参量近似熵的理论及算法,提出由近似熵的角度去分析短路过渡弧焊稳定性的思想,对指导实际焊接过程时的规范选择有参考作用.在焊接参数均满足匹配条件下,采集短路过渡的弧焊电流信号,对该电流信号的近似熵进行计算,结合传统的最佳电弧的理论认识,通过比较不同规范下近似熵的大小和近似熵的标准方差,探索得出近似熵与稳定性的规律.结果表明最佳的焊接规范具有近似熵较大,标准方差较小的特征,且在最佳的焊接规范中标准方差最小就对应着最佳电弧.     

激光+双丝脉冲MAG复合焊的焊接稳定性

研究激光和Ar+He混合气体中He气体体积分数对激光+双丝脉冲MAG复合焊焊接稳定性的影响。搭建激光+双丝脉冲熔化极活性气体保护(Metal active-gas, MAG)复合焊焊接系统,利用LabVIEW信号采集系统采集焊接电流和电弧电压波形,借助高速摄像系统同步拍摄电弧形态和熔滴过渡过程,实时监测焊接过程。观察后丝短路和前丝断弧情况并对前丝电弧电压进行单因素方差分析,研究Ar+He混合气体中He气体体积分数对焊接稳定性影响;比较焊接过程中激光的有无对熔滴过渡的影响,分析激光对焊接稳定性影响。结果发现随着He气体体积分数增大,后丝对应短路次数增多,当He气体体积分数为50%时,前丝出现断弧现象,大于50%,断弧时间随之增加,焊接稳定性变差;激光+双丝脉冲MAG复合焊和双丝脉冲MAG复合焊相比,加入激光可稳定电弧,为熔滴提供一附加力,该力促进熔滴过渡,使熔滴过渡尺寸减小,加大过渡频率,改善熔滴过渡,提高焊接稳定性。     

一种模拟控制式埋弧焊设备的数字化升级改造设计

该文设计了一套基于STM32的双单片机控制系统对模拟控制式埋弧焊设备进行数字化改造。该系统包括电源控制系统和过程控制系统,2个系统之间采用串行异步通信方式,实现命令和参数交换。可以实现焊接电源多种外特性输出,满足埋弧焊、焊条电弧焊、气体保护焊、碳弧气刨工艺需要。设计双闭环控制系统对送丝速度进行调节,设计单闭环控制对小车驱动电机进行控制。测试表明,改造后的焊机用途拓宽,人机界面丰富,引弧、焊接、收弧的稳定性和可靠性均大幅提升,具有很好的实用价值。     

Effect of laser on the welding process of short-circuiting transfer MIG welding of aluminum alloys

In this paper, the effect of laser on the welding process in metal inert gas (MIG) welding of aluminum alloys was studied exploiting high-speed imaging and welding electrical signals collecting. Bead-on-plate welding experiments were conducted using conventional short-circuiting transfer MIG welding and laser-short-circuiting transfer MIG hybrid welding. The obtained results point out that it took less time to strike the arc in laser-MIG hybrid welding, and the stability of arc striking was increased. When the laser was introduced into the arc atmosphere, the arc was compressed, and the welding energy was more concentrated. The arc cathode spot was fixed to the laser beam impinging spot, so the arc could burn stably. In laser-MIG hybrid welding, the droplet short-circuiting transfer stability and the weld appearance were improved significantly. Moreover, an analysis method of judging droplet transfer stability which bases on statistical techniques was proposed. By this method, it can be concluded that the short-circuiting transfer process became more stable in laser-MIG hybrid welding.     

保护套圈对步进式电弧螺柱焊过程电弧行为的影响

利用自行研制的步进式电弧螺柱焊枪,采用套圈作为焊接过程的保护方式,研究了套圈保护步进式电弧螺柱焊过程。对焊接过程的电流及电压波形进行采集,分析焊接过程的电弧行为。实验结果表明,在套圈保护下,步进式电弧螺柱焊过程电弧稳定燃烧,熔化金属短路现象明显减少;螺柱送进过程的“无弧”时间缩短。焊接过程电弧行为的改善提高了电弧对接头的加热效率;与无保护步进式电弧螺柱焊相比,套圈保护步进式电弧螺柱焊可以在一定范围内缩短焊接时间。     

步进式电弧螺柱焊中螺柱送进深度的自动控制

在分析螺柱送进过程的基础上,对步进式电弧螺柱焊过程中螺柱送进深度的控制问题进行了研究。以焊接过程中螺柱与工件之间的相对位移为控制量,采用位移传感器检测螺柱送进过程中焊枪弹簧压缩位移,以此获知螺柱与工件之间的接触状态,实现对螺柱送进深度的控制。试验结果表明,步进式电弧螺柱可以实现螺柱送进深度的自动控制,无需在焊前预先设置螺柱送进深度;采用不同螺柱提升高度进行焊接时,控制系统可以做出相应的调整,保证合适的螺柱送进深度。将此方法用于螺柱穿透焊,能够有效减小间隙对焊接过程的影响,保证焊接过程的顺利实现。     

Prevention of humping bead associated with high welding speed by double-electrode gas metal arc welding

Manufacturing productivity can be improved by increasing the welding speed. However, humping bead will occur when welding speed is beyond a certain value. An experimental system of double-electrode gas metal arc welding (DE-GMAW) was developed to implement high speed welding and prevent from humping bead formation. The DE-GMAW appropriately partition the heat energy between the wire and the base metal so that higher deposition rate of filler wire and suitable shape and size of weld pool are ensured. The arc images captured during DE-GMAW process were used to optimize the geometric parameters between the gas tungsten arc welding and the gas metal arc welding (GMAW) torches. The main arc and bypass arc integrated well and satisfactory weld bead formation was obtained. Through observing the weld pool behaviors from side view during DE-GMAW process, it was found that the height of both solidified and molten region at the pool tail is almost flat so that no humping bead was formed during DE-GMAW with the welding speed up to 1.7?m/min. The side view images of weld pool in DE-GMAW were compared with those in conventional GMAW, and the reason why DE-GMAW can suppress humping bead is shortly discussed.     

Analysis of arc welding process using Digital Storage Oscilloscope

During welding, random variations in current and voltage occur, which cannot be recorded with ordinary ammeter and voltmeter. Acquisition of voltage and current signals while welding is in progress at a very high speed using Digital Storage Oscilloscope (DSO) and subsequent analysis of the stored data can be very useful to understand the arc welding process. In the present study, welding data were acquired for two inverter and two generator power sources while welding with two different electrodes using a DSO at the sampling rate of 40,000 samples/s. This data was filtered using the Fast Fourier Transform (FFT) low pass filter and subjected to time domain and statistical analysis. Probability Density Distributions (PDDs) were used to evaluate performance of power sources and consumables. Results clearly differentiate between the arc characteristics for different power sources and consumables.     

潜艇耐压壳体埋弧焊过程参数计算机监测分析系统的研究

基于Windows2000，设计了潜艇耐压壳体埋弧焊过程参数计算机检测、记录和分析的软硬件系统。试验结果表明，该系统能较好地完成焊接电流和电孤电压信号的实时监测和记录，能及时捕捉到焊接参数的异常变化，能满足焊接生产长时间、不间断地实时监测和记录焊接工艺参数的需求，并能对焊接工艺参数进行分析，从而可对工艺参数的合理性进行评定。     

Study on arc characteristics and their influences on weld bead geometry in narrow gap GMAW of 5083 Al-alloy

As an efficient process, narrow gap gas metal arc welding (NG-GMAW) was employed to join thick plates of 5083 Al-alloy. In this paper, arc characteristics in NG-GMAW of 5083 Al-alloy and their influence on the weld bead geometry were studied with synchronous acquisition system for various groove types, welding modes, welding current levels, and swing frequencies. The arc profiles were measured and appear to be entirely different compared with that in bead-on-plate GMAW process, meanwhile the arc size changes with varied welding mode, welding current, and arc swing frequency. Arc characteristics highly affect the weld bead geometrical parameters such as bead width, welding penetration, sidewall penetration, and weld surface concavity. Linear regressions were made between the arc characteristics and the weld bead geometrical parameters both in swing and non-swing arc process. It showed that a negative linear correlation exists between welding penetration and arc length, sidewall penetration, and arc warpage, while a positive linear correlation exists between weld surface concavity and arc warpage in non-swing arc process. In contrast, a non-linear correlation exists among them and the variation tendency remains the same in swing arc process.