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Photoelectric Emission in the Arc

Photoelectric emission in the arc: UV light releases electrons from the metal, increasing electrical conductivity and stabilizing the welding process.

Physico-chemical mechanism of action

UV light from the arc column excites electrons in the metal. These freed electrons form an electric current that guides the cathode and supports the welding process.

Metallurgical relevance & risks when welding

Too strong photoelectric emission can lead to overexcitation of the metal, resulting in uneven weld seams and possible cracks. Low emission can slow down the welding process or make it unstable.

Shop practice & instructions

Ensure the arc column is correctly calibrated. A UV intensity of 100 mW/cm² is typical for stable emission. Continuously monitor the current flow and adjust the column if necessary.

MetallurgieSchweißtechnik

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