摘要
为了研究气压降低对电弧特性的影响,对不同大气压情况下的焊接工艺数据进行研究和机理分析。研究结果表明:自保护药芯焊丝的电弧静特性呈下降趋势;随着焊炬高度(电弧长度)的增加,电弧静特性曲线上移。在低气压环境下,电弧空间的气体密度和温度降低,导致导电粒子密度降低,焊接电流减小;焊接电弧的扩展,导致弧柱直径增大、电场强度降低,但阴极和阳极压降增加,仍使总电弧电压增加。由于低气压时的弧柱电场强度降低,电弧的自身调节能力减弱,电弧稳定性和弧柱挺度下降,从而影响焊缝成形和接头质量。在低气压地区进行自保护药芯焊丝电弧焊接时,必须严格控制焊接工艺参数,尽可能采用低电弧电压进行焊接。
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.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第7期734-738,共5页
Journal of Tsinghua University(Science and Technology)
基金
国家自然科学基金项目(51075231)
铁道部科技研究开发计划重大项目(2008G001-C)
铁道部科技研究开发计划重点课题(2010G025)
国家科技重大专项(2012ZX04012011)
关键词
电弧特性
低气压电弧焊接
自保护药芯焊丝
电弧扩张
arc characteristic
arc welding at low atmospheric pressure
self-shielded flux-cored wire
arc expansion
