Influence of low atmospheric pressures on the arc characteristics of self-shielded flux-core wire
ZHU Zhiming1, FAN Kaiguo1, LIU Han1, WANG Yongdong2
1. Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Tsinghua University, Beijing 100084, China;
2. School of Materials and Engineering, Heilongjiang University of Science and Technology, Harbin 150022, China
Abstract：The welding characteristics of self-shielded flux-core wire were studied experimentally and theoretically for various atmospheric pressures to study the influence of low atmospheric pressures on the arc characteristics.The results show that the static arc of self-shielded flux-cored wire tends downward but moves upward with increasing welding torch height (arc length). At low atmospheric pressures, the gas density and temperature decrease in the arc region, which reduces the conducting particle density and the welding current. The arc expansion increases the arc column diameter and decreases the electric field intensity. With the increase of the voltage drops in the cathode and anode, the total arc voltage increases. The decrease in the electric field intensity within the arc column at low atmospheric pressures reduces the self-adjustment ability of the arc, the arc stability and the arc column stiffness, which influences the weld formation and joint quality. The welding process parameters for arc welding with self-shielded flux-cored wire at low atmospheric pressures have to be strictly controlled and the arc voltage need to be as low as possible.
朱志明, 范开果, 刘晗, 王永东. 低气压对自保护药芯焊丝电弧特性的影响[J]. 清华大学学报（自然科学版）, 2015, 55(7): 734-738.
ZHU Zhiming, FAN Kaiguo, LIU Han, WANG Yongdong. Influence of low atmospheric pressures on the arc characteristics of self-shielded flux-core wire. Journal of Tsinghua University(Science and Technology), 2015, 55(7): 734-738.
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2015, Vol. 55 
