论文部分内容阅读
我们通常看到的弧光种类很多。以两根金属棒做为电极,分别连结电源两端,当电极瞬间接触立即分开后,并维持一定距离,此时由于电场的作用使两极间空气电离形成一个高温离子团,这个导电的高温热离子团所发出的热辐射光简称弧光。 目前工业上制造弧光电极的材料,除采用一些高熔点的金属如钨、钼、钽、锆等,更多的是使用碳素做为生产电极的基础材料。因为碳素具有独特的理化性能,在一般条件下碳素受温既使超过3500℃也不会出现熔融状态,而是直接升华,这一特性可使碳素电极在使用过程中始终维持原有的形状,直到全部消耗完毕为止。 另外,碳素电极的成本比金属电极低。采用纯碳素制成的电极所产生的弧光光强是有局限性的,这种电弧的温度只能维持在3500—4000K,既使增加电弧间的电流密度,也
We usually see a lot of arcs. Two metal rods are used as the electrodes to connect the two ends of the power supply respectively. When the electrodes are instantaneously separated and kept in contact with each other for a certain distance, the air between the two electrodes is ionized to form a high-temperature ionic group due to the electric field. At this time, The heat emitted by the ion mass is called arc light. At present, the materials used for manufacturing arc electrodes in the industry are carbon based electrode materials instead of high melting point metals such as tungsten, molybdenum, tantalum and zirconium. Because of its unique physical and chemical properties of carbon, carbon under normal conditions, even if the temperature exceeds 3500 ℃ does not appear molten state, but the direct sublimation, this feature allows the carbon electrode in the process of using the original Shape until it is completely consumed. In addition, the cost of the carbon electrode is lower than that of the metal electrode. The use of pure carbon electrodes produced by the arc light intensity is limited, the temperature of this arc can only be maintained at 3500-4000K, even increasing the current density between arcs