Union AlSi 7 Mg is a solid MIG/MAG wire for welding aluminium and its alloys. It works on frames, tanks, housings and light structures.
It is used on grades such as AlSi7Mg and AlSi7Mg0. The wire runs under shielding gas, fed continuously from a semiautomatic torch, and it suits both hand work and mechanised stations.
- Classification EN ISO: 18273 S Al 4018 (AlSi7Mg)
- AWS classification: A5.10 / SFA-5.10 ER4018
- Shielding gas: I1, I3
Degrease the plate and keep the surface dry, moisture is the main cause of porosity in aluminium welds. Watch the wire stick-out from the contact tip, too long a one lowers the arc voltage and worsens the fusion. Set the gas flow so the pool is covered over the whole length of the bead, and shield the station when you work in wind. The gas choice affects the shape of the face and the amount of spatter, so keep to the mixture given in the classification.
