Bubbling phenomenon of liquidized Sn-Bi-Li-Er alloy under hydrogen plasma exposure

A laboratory-scale inductively coupled plasma apparatus investigated the behavior of liquid Sn-Bi-Li-Er alloy (SBLE) under hydrogen (H-2) plasma exposure. By exposing the liquid SBLE to H-2 plasma, the bubbling of liquid SBLE and pulsive H-2 pressure increase was observed. Moreover, plasma density, i.e. ion flux, increased both bubble size and H-2 pressure spike. The simultaneous measurement of a high-speed camera and mass spectrometry concluded that the bubble was formed by H-2 accumulation, and similar to 38% of hydrogen ion flux contributed to the H-2 accumulation. Lithium hydride may be considered the bubble sphere's origin from X-ray photoelectron spectroscopy measurement of droplets produced from the ruptured bubble sphere. From the experimental results, the bubble formation mechanism was discussed.