Welding Precautions - Dual-Phase Steel

WELDING PRECAUTIONS - DUAL-PHASE STEEL

The proper equipment and settings must be used when welding Dual-Phase steel. MIG and resistance spot welding are the recommended methods. Surfaces must be clean and free of foreign materials.

ER70-S-6 is the recommended wire specification to use when welding Dual-Phase steel components.

Recommended gas mixtures are as follows: C02, 92Ar8C02, 84Ar16C02 and 77Ar23C02.

Components made of Dual-Phase steel should not be heated to straighten or repair. Severely bent or kinked components should be replaced with new ones.

Do not use Oxyacetylene equipment to weld Dual-Phase steel.
- The correct protective clothing should always be worn.
- Adequate ventilation must be provided to avoid the accumulation of poisonous gases.
- Use grinding discs and wire brushes dedicated to the type of material being welded.
- A test weld should always be carried out on a test sample.
- Follow equipment manufacturer's prescribed procedures and equipment settings for the type of weld being used.
- Disconnect the battery ground cable from the battery.
- Disconnect on-vehicle modules and protect them from possible heat damage and electrical currents when welding.
- Factory spot welds may be substituted with either resistance spot welds or MIG plug welds. Spot/plug welds should equal factory welds in both location and quantity. Do not place a new spot weld directly over an original weld location. Plug weld hole should equal 8 mm (0.31 in) diameter.
- Corrosion protection needs to be restored whenever it is necessary to sand or grind through painted surfaces or E-coat, or when bare metal repairs are carried out. Refer to Restoring Corrosion Protection Following Repair.