Non-Destructive Testing of Joints of Antifriction Parts Crimped by Pulsed Magnetic Deformation

Possibilities of non-destructive testing (NDT) methods to assess the quality of permanent joints of powder metal parts were evaluated. Antifriction bushing-bushing couples used in transport braking systems were investigated. The parts made of bronze graphite were crimped by pulsed magnetic deformation by means of electromagnetic equipment with a maximum discharge energy of 30 kJ. The gap between joint parts in the couples was assessed by ultrasonic and radiographic methods. A standard ultrasonic flaw detector Krautkramer USM-25 with an Olympus 4MHz dual-element echo transducer and an industrial x-ray apparatus YXLON EVO 200D were used, correspondingly. In first trial, both methods were equally sensitive to tight and weak connection of joints.