Acoustic Emission from Hydrogen Bubble Evolution during Pitting Corrosion of Flame-retardant Mg Alloy

摘要

In this work, the hydrogen bubble evolution in a single corrosion pit of a flame-retardant Mg alloy under a micro-droplet of NaCl solution was successfully filmed using the video microscope with concurrent AE measurement. Over 120 hydrogen bubbles and their signals were carefully analyzed, indicating that small bubbles of around 20μm diameter produced high-frequency low-amplitude AE signals, while relatively-big bubbles larger than 60μm diameter gave rise to relatively low-frequency high-amplitude signals.