The GMAW( Gas metals arc welding) can be divided into MAG welding and MIG welding according to the type of securing gas. MAG welding uses CO2, or a mix of C02 or oxygen (these are called reactive gases) in argon as a protecting gas. It is only popular to call CO2 gas welding as CO2 arc welding, which is various from MIG welding, which makes use of argon, helium and also various other inert gases.
Co2
Pure Carbon Monoxide ₂ is a kind of colorless, odorless, oxidizing active gas with a density of 1.97 Kg/m3 (much heavier than air1.29 weldermetals co.,ltd Kg/m3). It is mostly utilized for welding low carbon steel as well as reduced alloy steel.
To avoid the oxidation of CO2, It's required to make use of the deoxidizing cable including Si, Mn and various other deoxidizing aspects throughout welding. Steel spatter exists in CO2 gas welding especially when the welding criteria are not ideal, harsh appearance, the weld swimming pool is deep and also slim, and very easy to create fractures and also pores., the forming is substandard to that of AR for a bigger diameter of the welding cord. It is usually needed that its pureness needs to not be much less than 99.5%.
Argon + co2
Ar+ CO2 mix is widely used in welding carbon steel and low alloy steel. It incorporates the advantages of Ar gas and CO ₂, generating a stable arc, small splash, simple to get axial jet shift, and also because of oxidation, it overcome the arc drift as well as inadequate weld formation triggered by a solitary Ar gas welding.
The blending proportion of Ar and also CO2 is normally 80% Ar +20% CO2 or 82% Ar +18% CO2, which can be utilized for both jet transition arc and short circuit transition arc. The cost of this gas is more than that of pure CO2, but has a great influence toughness of the weld metal (the influence sturdiness of the weld metal decreases with the increase of CO2 material), particularly the sprinkle is smaller than that of pure CO2, and there is practically no sprinkle when the jet change.
Ar+ CO2+ O2.
A large number of examinations have actually confirmed that the blend of 80% Ar +15% CO2 +5% O2 is the best for welding reduced carbon steel and also low alloy steel, and also it has excellent performance in regards to welding surface area form, melting deepness, joint top quality, metal bead change and also arc security. The weld deepness profile is triangular, and the weld surface is flat. The cross section shape of the weld is far better than that obtained with various other gases.
