← Glossary

Fluorescence intensity

Fluorescent intensity is the strength of visible light emitted by a penetrant under UV light. High intensity improves contrast and the detectability of discontinuities.

Physical-Chemical Mechanism of Action

A penetrant emits visible light when it absorbs UV light. The intensity of this light depends on the type of penetrant and the strength of UV radiation.

Metallurgical Relevance & Risks in Welding

High fluorescent intensity facilitates the detection of pores, cracks, or other material flaws in the weld. A too weak emission level can cause smaller defects not to be visible and thus to be overlooked.

Workshop Practice & Instructions

Use a UV light with an intensity of at least 10 mW/cm². Make sure the penetrant has a fluorescent intensity of at least 50%. Hold the UV light over the weld for 30 seconds.

MetallurgieSchweißtechnik

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