Acoustic emission monitoring of single cracking events and associated damage mechanism analysis in indentation and scratch testing

摘要: Abstract A detailed study on optimisation of single cracking events in indentation and scratch testing brittle coatings is presented. These results are illustrated for nitrogen-doped stainless-steel deposited by reactive magnetron sputtering. The best obtained with a resonant piezo transducer the indenter shaft high-speed electronics allowing detection cracks. Waveforms seen to contain only information crack energy instant nucleation. latter exploited precise synchronisation all test-specific parameters real image failure. With this approach, it possible carry out an advanced failure mechanism analysis test-induced surface damage. This practised indentation, where occur elastically strained region outside contact area (size plastic indent). shape indent be unmodified elastic recovery unloading. In testing, clear correlation between high-energy AE pulses achieved, first attempts analyse prevailing mechanisms experimental ‘dead times’ separation consecutive