What is Porosity?
Porosity is gas pores found in the solidified weld bead. These pores may vary in size and are generally distributed in a random manner. Causes may be:
- Inadequate shielding gas flow.
- Excessive shielding gas flow. This can cause aspiration of air into the gas stream.
- Clogged gas nozzle or leaking hoses & fittings.
- Excessive wind in the welding area.
- Foreign matter on the wire like excessive lubricant.
- Puddle turbulence caused by erratic arc characteristics (voltage too low or high)
What is Undercutting?
Undercutting is a defect that appears as a groove in the parent metal directly along the edges of the weld. Causes may be:
- Travel speed too high.
- Welding Voltage too high.
- Excessive welding current.
- Insufficient dwell at the edge of the weld bead.
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