What is the primary role of a developer in liquid penetrant testing?

In liquid penetrant testing, the primary role of a developer is to enhance the visibility of the indications that reveal defects on a surface. The developer is applied after the penetrant has been removed from the surface, and its purpose is to draw the penetrant out of any flaws or cracks, making these defects visible under inspection. By creating a contrast between the penetrant and the surface, it allows for easier identification of any discontinuities that may affect the integrity of the material being tested.

While cleaning the surface, providing illumination, and applying the penetrant are important steps in the testing process, they are not the primary roles associated with the developer itself. The developer's specific function is focused on visibility enhancement which is crucial for accurate detection and evaluation of defects in various structures and materials.