| 摘要 |
<p>An improvement in liquid penetrant inspection techniques for detecting surface discontinuities wherein a liquid penetrant is applied to the surface to be tested so that it finds its way into discontinuities, excess penetrant is removed, and then a developer suspension is supplied to the surface to absorb penetrant which has become lodged in surface discontinuities. The specific improvement of the present invention resides in using in the penetrant a compound which undergoes a color-forming reaction with solid particles contained in the developer suspension. The color-forming reaction renders the particles constrastingly visible to the background.</p> |
