Nondestructive Evaluation of BSCC Artificial Heart Valves

The subject of investigation is a set four artificial heart valves made electrically conductive material, namely the alloy Ti-6Al-4V. Notches defined geometry with gradually increasing depth were formed on these BSCC (Bjork-Shiley Convexo-Concave) valves. These defects are created so-called output strut, which serves as support mechanism for controlled movement occluder disc and they have been investigated. method was used ultrasonic infrared thermography, where object excited by UTVIS EDEVIS system response detected FLIR SC 7200 camera. postulate use this that excitation signal may be periodically pulsate or in any other way modulated certain amplitude frequencies, called "lock-in frequency". Lock-in thermography type active lock-in method. results damage detection relatively complicated objects compared discussed.