Revealing thermal-mechanical hybrid ablation mechanism in carbon fiber reinforced plastic laser cutting by acoustic emission monitoring

Abstract

The ablation mechanism of CFRP laser cutting refers to complex thermal and mechanical behaviour, and should be investigated. Two processing mechanisms of thermal ablation (TA) and mechanical denudation (MD) were found. TA resulted from the vaporization of the material formed by the accumulation of laser energy, which is reflected by RMS of AE signal < 0.14 V. MD resulted from the material that was stripped from the substrate under the impact of the plasma plume, which is reflected by 0.14 V < RMS < 0.175 V; The processing mechanism of MD exists simultaneously in the same trajectory and adjacent trajectory scanning. When the mechanism of MD in the same trajectory scanning is most severe, RMS also reaches the maximum value of 0.23 V; The RMS has the same variation law as the material removal rate. When the removal rate reaches the maximum value of 12.2 × 107 μm3/s, the RMS curve also reaches its highest point, and the model prediction accuracy is greater than 89%.