摘要：建筑石膏粉经 250～500 kGy 剂量 β 射线辐射后，颗粒微观 形 态 规整度提高，粒径在 50.9～62.6 μm 的颗粒比例减少了 24%，几乎没有 粒径大于 62.6 μm 的颗粒。 SEM 图像表明，经辐射后，建筑石膏粉中有 尖锐棱角的颗粒减少，片状颗粒与针状颗粒比例减少，柱状颗粒与粒状 颗粒比例增加。 参照 GB9776-88 制成标准样进行强度测定，试块的抗 折强度比原来提高了 22%～30%。 

关键词：建筑石膏；辐射；抗折强度；表面修饰

Abstract：The results concerning the influence of β-ray radiation for the gypsum were presented. After β-ray radiation， the overall form of the gyp sum particles was much more regular and the particles of 50.9～62.6 μm were reduced by 24%， and there was nearly no particles larger than 62.6 μm. The morphology of the gypsum particles and the set gypsum was stud ied by scanning electron microscopy. The SEM images showed that the ra diated gypsum particles had fewer particles with sharp edges；the propor tion of needle-like particles and sheet particles was reduced；the proportion of cylindrical particles and granular particles was increased. The results showed that the flexible strength of the standard set gypsum made of radi ated gypsum particles was increased by 22% to 30%. 

Keywords：building gypsum；radiation；flexible strength；surface modified