Ultrasonic testing (UT) is an indispensable component of quality inspection for aluminium extrusion billet and forging stock.
Depending on the application, fully automatic linear or helical stations are available to be integrated in the production flow or installed as stand alone installations, as required.
Testin of cast billets for centre cracks and cavities has been standard practice in aluminium casthouses for many years, however, usually with portable hand-held UT equipment, which means only random checks are made.
For the production of highly stressed components, particularly for the aircraft and automotive industries, reliable examination of all billet material used is mandatory. Ultrasonic testing should be performed directly after casting to avoid costly further processing of faulty material.
Representative requirements of ASTM B594 standards class-A (1,2 mm flat bootom hole reflection) and class-B (2,0 mm flat bottom hole reflection) sensitivity are typically achieved.
For quality control of billet surface Hertwich has developed a billet surface inspection using 3D camera technology in order to reliably detect surface defects on aluminium billets caused by the casting process.
Helical ultrasonic testing