电弧

The content of this course mainly include the feature, equipment, principle and application of high efficient welding method, for example, activating flux assisted TIG welding, narrow gap TIG welding, hot wire TIG welding, oscillating arc TIG welding, plasma TIG welding tandem MIG welding, hybrid arc welding, surface tension transfer MIG welding, oscillating arc MIG welding, mixed-gas MIG welding, two wire or more SAW welding, friction stir welding and laser-MIG hybrid welding, etc.

主要内容涉及到助焊剂TIG焊技术、窄间隙TIG焊技术、热丝TIG焊技术、摆动电弧TIG焊技术、等离子弧焊技术的基本原理、设备、特点和应用。双丝焊MIG方法、复合电弧技术、表面张力过渡、摆动电弧MIG、交流MIG焊、混合气体MIG焊的原理、特点、设备和应用。双丝以及多丝埋弧焊技术、窄间隙埋弧焊技术的原理、特点和应用。搅拌摩擦焊以及激光电弧复合焊接的原理、特点、设备、应用范围。

After the related researches on the arc spraying technology,it is quoted in the textthat arc spraying can be synthesized by the change of the elements of the manufacturingtechnology of Al_2O_3 millimian powder by reactively synthesized arc spraying has beenstudied experimentally.

本文在对电弧喷涂技术进行相关研究后，提出了改变电弧喷涂雾化气体成分，利用反应合成电弧喷涂的方法，试验研究了反应合成电弧喷涂制备Al_2O_3纳米粉体的技术。

By studying the growing situation of AC arc along the simple plane model and measuring of AC arc performance using electrical probe, we obtained the requirement of AC arc to develop along a polluted surface under various pressures and a method to calculate the AC pollution flashover voltage.

通过对沿简单平板染污模型交流电弧发展情况的研究，用探针对交流电弧特性进行了测量，提出了交流电弧的发展条件和一种计算交流污闪电压的方法，得出简单模型交流污闪电压随气压下降而降低的主要原因是由于低气压下所要求的交流电弧发展条件降低。

Based on the developed variable polarity TIG welding power supply ,it establishes variable polarity TIG welding arc multi-information measuring and processing system by adopting memory oscilloscope,high speed video-recorder?spectrograph?welding arc dynamic analyzer and computer.

以研制的变极性TIG 焊接电源为实验平台，采用记忆示波器、高速摄像仪、光谱分析仪、焊接电弧动态分析仪，建立起变极性TIG焊接电弧多信息测试分析系统，同时采集焊接电流、电弧电压、电弧形态和电弧光谱等重要信息，并基于VisualC++语言开发的软件系统对采集的各种信息进行融合及分析。

On the basis of experiment analyses we would got that, When arc met with chute, it was blocked and had a stagnation, this made hot gas flow incrase near the chute; After arc went into the chute, mental vapor from arc root would lower the dielectric strength near the chute, meanwhile, High value of arc voltage and the corase face of the chute made electric strength increase. These factors might give rise to local restriking near the chute, and made arc voltage drop suddenly.

总结实验结果并加以分析，本文提出了这样的观点：电弧进入栅片时，在入口处受阻后的停滞，会使该区域的热气流增加；进入栅片后，弧根蒸发的金属蒸汽、电弧热气流会降低栅片入口区域的介质强度；电弧被栅片分割后，电压急剧上升，再加上栅片表面的不均匀会使局部区域的电场强度显著增加，这些因素的综合作用会导致电弧在栅片入口附近发生局部重击穿，引起电弧电压电压跌落。

The platform of arcing experiment is composed of the arc fault generator and the current monitoring and saving unit, and several load appliances, then recommends the experimental process and the instruct of the equipments.

说明了电弧的基本性质，产生原因和故障电弧的危害，AFCI的结构和故障电弧检测的基本原理和我们研制的AFCI的技术路线。电弧试验半台由电弧发生器，录波设备和负荷设备构成。

It can be concluded from the above experiment results that for the auxiliaryheated arc plasma generator, an area which has uniform temperature distribution andhigher temperature. In this area, the diameter of the key arc root increases and thiscondition is beneficial to reduce the cathode erosion. At the same time, it is animportant segment for the secondary arc to rotate on the cathode surface and to heatthe surface for the auxiliary heated arc plasma generator.

总结上面的实验结果可以看出：在辅助加热电弧等离子体发生器中，利用辅助电弧对阴极表面的加热作用，能够在阴极表面形成一个温度较高且分布均匀的区域；在温度较高的区域内，主弧弧根直径增大，这种情形有利于减小阴极烧损；同时，辅助电弧旋转加热阴极表面是辅助加热电弧等离子体发生器的一个重要环节。

Arc plasma has many advantages, such as high temperature、 high energydensity and so on. It has been applied in the field of cutting、 welding、 metallurgyand material prepared etc, but there is a long-term problem in the field of the arcplasma technology, which is how to reduce cathode erosion to increase the life-timeof arc plasma generator, so many scholars in the world have been studying theproblem on the cathode erosion.

电弧等离子体具有温度高、能量密度大和对环境污染小等特点，它已被广泛应用于切割、焊接、冶金、材料制备等领域，但是在电弧等离子体技术中，怎样减少阴极烧损提高等离子体发生器的寿命是电弧等离子体技术中一个长期问题，因而国内外的许多学者仍在对阴极烧损这个问题进行研究；本文围绕&通过提高阴极表面温度，增强阴极表面的电子发射能力，来增大阴极弧根直径，进而降低电弧通过阴极弧根传入阴极表面的有效比热流，以达到减小阴极烧损的目的。&

In order to avoid or reduce arc fault hazard,the authors established an arc fault detecting test system with the method of power spectral analysis to study the early acoustic characteristics of fault arc ,and extracted the sound signature of early fault arc by using power spectrum analysis.

为了避免或减少故障电弧的危害，笔者建立了故障电弧探测试验系统，采用功率谱分析的方法对故障电弧的早期弧声特性进行了试验研究，提取出故障电弧的早期弧声特征信息。

Saddle shaped AMF can produce a radial expanding force, which has more effective effect on resisting the pinch effect of self-generated azimuthal magnetic field of arc current. This effect of saddle shaped AMF can keep vacuum arc in diffuse mode under much higher current. So the limiting current interruption capacity of vacuum interrupter can be enhanced.

为了进一步提高纵向磁场对真空电弧的控制作用，本文提出在真空灭弧室的触头间引入从触头中心向边缘逐渐增强的非均匀纵向磁场，马鞍形纵向磁场会对真空电弧产生一个径向扩张力，而纵向磁场分布的合理设计可以使这一扩张力进一步抑制真空电弧自生环向磁场对电弧的箍缩作用，从而使真空电弧在更大的电流时仍能保持在扩散态，使真空灭弧室的极限电流开断能力得以提高。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。