拉长电弧的等离子喷枪设计与弧压测试

针对在普通等离子喷涂的生产中，喷涂的涂层可靠性和重复性差等缺点，设计了拉长电弧的等离子喷枪．该喷枪能够提高电弧电压并减小电弧电压波动．提出了一种拉长电弧的实用喷枪结构，成功地解决了统一水冷的两喷嘴间的绝缘密封及连接问题．对喷枪测试的结果表明，喷枪的电弧电压波动幅值小．对电弧电压波形的傅里叶变换表明，电源引起的波动是这种喷枪电弧电压波动的主要因素，而喷枪电弧阳极斑点游动引起的波动很小．

Design of a Plasma Spray Torch of Elongating Arc and the Arc Voltage Tests on It

A plasma spray torch of elongating the arc was designed in order to overcome the shortcomings that the reliability and reproducibility of plasma sprayed coatings are imperfect in the traditional plasma spray process.The torch can bring higher arc voltage with lower fluctuation by elongating the arc.The problems of insulation and sealing of the two anodes,which are water-cooled together,are successively solved.A practical structure in the engineering was presented which greatly improves the capability of the plasma torch.The results of the tests show that the arc voltage fluctuation amplitude(peak-to-peak) represents almost 10% of the mean level.The Fourier transition of the arc voltage waveforms shows that the fluctuation of them is mainly attributed to the fluctuation of power supply,while the motion of arc root has little effect on them.