Welding is a kind of processing technology which make a permanent connection between the materials. Fusion welding is used most widely among a variety of welding methods. And the most important method of fusion welding is arc welding.

The main source of heat of arc welding is the arc generated between the electrode and the base material. People use arc to melt welding wire and base metal. There is bath on the base metal and it becomes welding line after cooling. The effect of arc on the arc welding is crucial as the main heat resource.

What is arc stability? It’s the extent that arc in the welding process to maintain a stable combustion without breaking arc, magnetic partial blown phenomenon. The stable arc has the advantages of stable smelting process, small variation of arc length and less short-circuit flying. The weld penetration depth, melting width and excess height are all suitable. The welding seam is beautiful and the welding quality is high. On the contrary, if the arc combustion instability, making the molten droplet transition when the phenomenon of serious irrigation, poor weld formation, welding seam shallow, as well as the formation of pores or slag defects, welding quality will be low. Factors affecting the stability of the arc includes power type and characteristics, welding current, welding voltage, electrode coating and flux composition, as well as partial magnetic arc blowing etc. The operator's proficiency and the cleanliness of the workpiece surface will also affect the arc stability.

How to improve the stability of welding arc in production?

1.For the welding method using AC power source, the arc stability problem is mainly the difficulty of arc re-ignites when the current crosses zero, and the stability of the arc can be improved by adding the pulse current or series inductance in the welding circuit.

2.The distance between the two welding wire affect the stability of the arc in double wire welding, so the two-wire spacing should be properly adjusted.

3.The addition of arc stabilizer in the welding wire increases the ionization degree of the arc space, and the charged particles are more likely to be generated, the arc stability can be improved.

Welding plays an important role in industrial production and modernization. It is very important to monitor welding quality. Arc stability is an important factor affecting welding quality. It is impractical to achieve the desired steady state of the arc, so the influence of other factors on the stability of the arc should be minimized to improve the welding quality.