A company was developing a new line of non-ferrous fasteners. To form the product, a titanium rod went through several high-speed steps to completely fabricate the threaded aerospace fastener. However, titanium is generally difficult to form at low temperatures, and surface flaws may easily develop. The engineers needed an inspection method that would identify problem areas during product development.
The capillary action of penetrant inspection was used to reveal surface breaking cracks. Liquid penetrant inspection was the most cost-effective choice of available methods for this application. Clean and dry parts were inspected for surface flaws under UV-A (black light); the indications formed by flaws were highly visible. The penetrant testing easily located all surface-breaking flaws in the prototype fasteners. After testing, these problem areas were identified so that the manufacturing process could be revised and minimize their occurrence.
Typical fluorescent indications noted on the titanium fasteners.