Fig. 5: Measurements of melt pool/plume stability under varying input energy density.
From: The interplay between vapour, liquid, and solid phases in laser powder bed fusion
a Plot of keyhole area (error bars: standard deviation ±σ), showing the melt pool becomes increasingly unsteady as the input energy density increases. b Average intensity difference between consecutive frames. The red dotted line indicates a step increase in average intensity difference for the schlieren images at E = ~70 GJ m−3 that marks the transition from stable to chaotic plumes, and thus, depression instability.
