Which inspection method is preferred for detecting fine cracks in glass?

The electrified particle method is effective for detecting fine cracks in glass due to its ability to utilize magnetic fields to draw attention to surface defects. This method involves applying a fine powder that is attracted to the surface cracks using an electric field. As the powder accumulates in these cracks, it highlights their presence, making them more visible for inspection.

This method is particularly advantageous for non-ferrous materials, like glass, because it can reveal hairline cracks that might not be easily seen through visual inspection alone or detected with the more traditional magnetic particle testing methods. The combination of electrical charge and powder helps in sensitively highlighting defects, ensuring they are identified.

In contrast, while other methods such as visual inspection can be useful for surface flaws, they may not effectively illuminate fine cracks. The fluorescent penetrant method is suitable for many surface defects but is generally more appropriate for porous materials or metals. The dry powder method is also limited in sensitivity when it comes to detecting very fine cracks, especially in non-metallic substrates. Thus, the electrified particle method stands out for its precision and effectiveness in revealing fine cracks in glass.