← Glossary

Contrast Medium Residue

Penetrant residue is unwanted leftover dye after the washing step, which can cause false indications in crack testing.

Physicochemical Mechanism of Action

Penetrant residue is leftover chemical compounds in and around the weld. It discolors the metal, leading to blurry or missing features in crack testing photos.

Metallurgical Relevance & Welding Risks

Some penetrants can't be fully washed off and stay in the material. This can mess up the visual inspection of cracks, leading to misjudgments in quality control. It also increases the chance of mix-ups in the shop.

Workshop Practice & Instructions

To minimize penetrant residue, make sure to wash thoroughly after welding. Use enough washing fluid and let it cool down slowly. In stubborn cases, a second cleaning with a special deoxidizer might be needed.

MetallurgieSchweißtechnik

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