DESIGN AND ASSEMBLY OF AN ULTRASONIC FATIGUE TESTING MACHINE

The lifetime approach in fatigue design based on S_N curves establish an infinite life when the cyclic stress applied is below than the endurance limit. Results in this field revealed fatigue failures beyond 10e7 cycles, indicating that theres no endurance fatigue limit, however obtaining this data with servo-hydraulic testing machine can be very time- consuming and expensive. Ultrasonic fatigue testing machines are a new generation of devices designed to perform VHCF tests in a very short time. This paper describes the design and assembly of an ultrasonic fatigue testing device working at 20 kHz.