作　　者： ; ; ;

机构地区： 北京航空航天大学

出　　处： 《稀有金属材料与工程》 2013年第S2期18-22,共5页

摘　　要： 基于研制的超音频快变换直流脉冲等离子喷涂电源,开展了超音频快变换直流脉冲等离子喷涂电弧特性研究,重点研究了脉冲电流频率、占空比等特征参数对电弧的伏安特性和电弧形态的影响。结果表明:复合超音频脉冲电流后,喷枪两端的电弧电压增加,电弧的功率相应地得到提高;电弧尾焰径向收缩显著,最大截面收缩率为47.6%,大大提高了电弧尾焰的电流密度;电弧尾焰的长度增加,延长了粉末的加热时间,粉末加热更加充分。脉冲电流频率20 kHz左右、占空比约50%时,可得到最佳的电弧尾焰径向收缩和长度增加。 Based on the developed ultrasonic frequency fast-convert pulse plasma spraying power supply,research on the pulse plasma arc characteristics has been done,especially the volt-ampere characteristics of plasma arc and arc shape.The results show that after the DC spraying the current is compounded with ultrasonic frequency pulse current,the arc voltage of spray gun will be significantly increased and the arc power can be improved accordingly.The diameter of the tail flame decreases obviously,the maximum shrinking rate of section of tail flame can be up to 47.6%,and thus the current density of tail flame increases greatly.The length of tail flame increases,which can extend the heating time in the arc of spray powder,making the powder be heated more fully,and it is helpful to improve the quality of the coating spray.When the pulse current's frequency is about 20 kHz and the duty cycle is about 50%,the best shrinking rate of section and the increment of tail flame's length can be obtained.

关 键 词： 超音频脉冲 等离子弧 伏安特性 电弧形态

领　　域： [金属学及工艺] [金属学及工艺]