脉冲强流电子束轰击对玻璃表面状态的影响

INFLUENCE OF PULSED HIGH-CURRENT ELECTRON BEAMS BOMBARDMENT ON SURFACE STATE OF GLASS

用脉冲强流电子束在真空度为 8× 10 - 3Pa下轰击钠钙硅酸盐玻璃 ,束能、束流、束径、脉宽和能量强度分别为 2 9keV ,10kA ,60mm ,5 μs及 4J/cm2 。当强流电子束射入到玻璃靶 ,瞬时间微区产生的最大功率密度达 10 1 2 W /cm2 ,电子束能量和电荷的沉积导致玻璃表面产生热应力 ,接着出现微裂纹。用金相显微镜和原子力显微镜 (AFM )观察微裂纹的形貌。结果表明微裂纹图象与Griffith裂纹相似。这可能是射入的电子束将Griffith裂纹扩展所致。经电子束轰击后 。

The soda_lime silicate glass was bombarded by pulsed high current electron beams under 8×10 -3 Pa vacuum. The beam energy, beam current, beam diameter, pulse width and energy intensity are 29 keV, 10 kA, 60 mm, 5 μs and 4 J/cm 2, respectively. When the high current electron beams project onto glass target at a instantaneous, the maximum power intensity produced is up to 10 12 W/cm 2 in micro_region. The deposition of beam energy and electric charges leads to generation of thermal stress in the glass surface subsequent the micro_cracks appear. The morphology of the micro_cracks was observed by metallographic microscope and atomic force microscope (AFM). The results show that the micro_cracks patterns are similar to Griffith cracks. It is possible that the micro_cracks are caused by Griffith cracks that may be expanded with injecting electron beams. After electron beams bombardment the hydrophilicity of glass surface increases.