Parameterized study and experimental validation of the time resolved heat source for material irradiation under hollow-cathode nanosecond pulsed electron beam

Transient hollow cathode discharge (THCD)-based nanosecond-pulsed electron beams facilitate precise thermal modification of material surfaces via dynamic energy transfer. However, existing models for THCD-based electron beams fail to fully capture the dynamic characteristics of the beam source's discharge, resulting in inaccurate capture of the temporal evolution of the electron beam's energy and current distribution. Based on the experimental measured e-beam properties, this study utilizes the simplified time resolved heat source model representing the nanoseconds beam-material interaction: a former volumetric heat source for initially high-energy e-beam and a later surface heat source for conducting stage low-energy high current e-beam. Through FEM based heat transfer simulations, the model adequately predicts temperature distributions after nanoseconds pulsed e-beam irradiation, and the influence of heat source parameters on the temperature field distribution, melt layer properties and dT/dt are discussed. Experimental validation with Ti-6Al-4V titanium alloy confirms its ability to describe irradiation morphology under varying energy storage. These findings provide a robust framework for optimizing electron beam applications in material processing.