Dec. 30, 2020
In the process of CO2 welding, molten metal particles and slag often fly around.
There are three kinds of spatter in CO2 welding. The first is spatter caused by short circuit.The second is the spatter caused by gas precipitation;The third is the splash caused by free transitions.
In the late stage of droplet short circuit forming metal bridge, due to electrical explosion caused by the splash, also known as the normal short circuit spatter.This splash is very small in small currents, and the amount of splash is very small.
When the current is large, instantaneous short circuit often occurs, that is, liquid metal bridge is formed in the early stage of short circuit, which often causes large electric explosion spatter.
At high current, the loop inductance is small, once the short Louie causes the droplet with the molten pool of the strong splash.
Under the condition of large current, thick wire and low voltage, it is usually submerged arc welding, once short circuit occurs, it will rush out the molten steel in the molten pool and form spatter
Due to arc initiation or wire feeding too fast will cause short circuit between welding wire and molten pool solid, then the welding wire may burst in segments, causing spatter
When welding, caused by metallurgical factors, the molten pool and droplets are filled with CO2(or CO) gas, and the gas escapes or bursts due to excessive internal pressure, often accompanied by spatter
In the free transition, due to the contraction of CO2 arc, the arc focuses on the bottom of the droplet and causes the droplet to deviate from the axis of the welding wire, making the droplet fly away in the form of rotation when it falls off or explode with a large current passing through the thin neck between the droplet and the welding wire.
Spatter is one of the main process problems in CO2 welding.There are two main ways to produce spatter. One is the spatter caused by the electrical explosion of the short-circuit bridge.The other is splashing caused by metallurgical factors.
