不同分离速度小电流滑动摩擦单电弧行为及烧蚀危害

Behavior and Ablation Hazard of Small Current Sliding Friction Single Arc at Different Separation Speeds

使用自制单点式载流摩擦试验机,采用球(T2铜)/板(T2铜)载流摩擦副,在电流20 A、电压20 V、水平相对滑动速度为10 mm/s的条件下,研究单载流摩擦伴生电弧及其危害。研究结果表明:单伴生电弧的演变过程可分为萌生、金属蒸汽电弧、过渡、空气电弧及湮灭5个阶段。随着时间变化,电流逐步减小,电压逐步增大,最终达到开路电压。中间3个阶段的功率相差不大,电弧功率达到稳定值时,其大小约为110 W,约是滑动接触时消耗功率的5.5倍。单电弧的烧蚀区域存在熔融区、喷溅区、溅落区和热影响区,但熔融区、喷溅区、溅落区3个区域的界线和方向不明确。小电流单电弧条件下,板试样的烧蚀区表面变得光滑平整。随着分离速度的增加,单电弧的功率和燃弧时长变化不大。单伴生电弧的最大弧长逐渐增大,烧蚀区面积先减小后增大,烧蚀区的表面平整程度增大。

It was difficult to study the associated arc deeply by common current-carrying friction testing equipment.A self-made single point current carrying friction tester was used in this paper,and the ball(T2 copper)/plate(T2 copper)sliding current carrying friction pair was used.Under the condition of current 20 A,voltage 20 V and horizontal relative sliding speed 10 mm/s,the single current carrying friction associated arc and its harm were studied.The results show that the evolution process of single associated arc is divided into five stages of initiation,metal vapor arc,transition,air arc and annihilation.With the change of time,the current decreases gradually,the voltage increases and finally reaches the open circuit voltage.The power of the middle three stages is not much different.The stable value of arc power is about 110 W,which is 5.5 times of the power consumed in sliding contact.There are melt zone,splash zone,splash zone and heat affected zone in the ablation zone of single arc,but the boundary and the direction of melt zone,splash zone and splash zone are not clear.The surface of the ablation zone becomes smooth under the condition of small current single arc.With the increase of separation speed,the power and arc burning time of single arc change little.The maximum arc length increases gradually,the area of ablation zone decreases and then increases.The surface leveling of the ablation zone increases.