碳化硼锆合金可燃毒物中空芯块制备工艺研究

Study on Preparation of B_4C-Zircaloy Annular Burnable Absorber

以氢化锆粉与碳化硼粉为原料，用橡胶模成型方法成型，真空烧结炉中脱氢；在800～1100℃下保温1h，制得碳化硼锆合金可燃毒物中空芯块烧结体；用浸渍法测量芯块的致密度和开孔率，研究烧结温度和碳化硼含量对烧结体致密度的影响；用扫描电镜分析坯体与烧结体的微观结构。结果表明，碳化硼锆合金烧结体的致密度随烧结温度的升高而增加，随碳化硼含量的增加而降低，碳化硼颗粒在锆合金中分布比较均匀，当碳化硼质量分数为O．5％，烧结温度在1000℃以上时，烧结体致密度达到95％以上，开孔率低于1％。

B4C-zircaloy annular burnable absorber pellet was prepared by powder metallurgy method, using Zr-2 hydride powder and BaC powder as raw materials, compacted by rubber isostatic pressing method, dehydrogenated in vacuum furnace. It is sintered at 800-1100℃ about an hour. The theoretical density and open porosity were tested by immersion method. The effect of the BaC content and sintering temperature on the sintering performance of the B4C-Zircaloy were studied. The microstructure of green body and sintered body were analyzed by SEM. B4C hinders the densification of sintered body, the relative density of the sintered body were increasing with the decreasing of B4C content and increasing of sintering temperature. The particle of BaC distribute uniformly. When the B4C content was 0.5% and the sintering temperature above 1000℃, the relative density of the sintered body reaches 95%, and the open porosity is lower than 1%.