In what way does contamination affect Liquid Penetrant Testing?

Contamination can significantly interfere with the Liquid Penetrant Testing (PT) process by creating false indications of defects. When a surface is contaminated with substances such as oil, grease, dirt, or corrosion products, these contaminants can impede the ability of the penetrant to effectively enter and fill any discontinuities. As a result, instead of revealing true defects, the testing may show false positives, leading to misleading interpretations.

In contrast, enhancing penetrant performance, having no effect on testing outcomes, or increasing the sensitivity of penetrant are not accurate reflections of contamination's impact. Contaminated surfaces would generally lead to reduced effectiveness of the penetrant, not enhanced performance. It is crucial to ensure that surfaces are clean and free from any contaminants prior to applying penetrant for accurate and reliable testing results. Proper surface preparation is a key factor in achieving valid results in Liquid Penetrant Testing.