Acoustic Emission during High-Cycle Fatigue Testing

Abstract

Acoustic emission (or stress wave emission) is measured during high-cycle fatigue testing of pure aluminium specimens. Experimental results obtained are as follows:
(1) Burst-type acoustic emission begins to radiate intermittently in the early stage of fatigue testing before the macroscopic crack growth is observed.
(2) Smoothed specimen radiates acoustic emission of several mV peak. Notched specimen radiates much larger acoustic emission of scores of mV peak under the same cyclic load.
(3) Most of the acoustic emission signals are detected around the instance that the cyclic load attains a maximum.
(4) It is clear that the acoustic emission measurement using a peak voltmeter is useful for the study of fatigue, particularly that of microscopic fatigue crack growth.