碳化硼粒径对可燃毒物成形与烧结性能的影响  

Effect of the particle size of B_4C on burnable absorber pellet in die pressing and sintering processes

作　　者：李圆圆[1] 朱常桂[1] 代胜平[1] 杨静[1] 乔慧武[1] 

机构地区：[1]中国核动力研究设计院反应堆燃料与材料重点实验室,成都610041

出　　处：《粉末冶金技术》2013年第4期248-252,共5页Powder Metallurgy Technology

摘　　要：以碳化硼微粉和氢化锆-2粉为原料,用钢模成形方法在200~500MPa的压力下制备了碳化硼氢化锆坯体,坯体在高真空烧结炉中于1 100~1 300℃下烧结1h制得碳化硼锆合金可燃毒物中空芯块。用扫描电镜分析坯体的微观形貌,研究了成形压力与碳化硼含量对坯体和烧结体相对密度的影响。结果表明：碳化硼的粒径对粉料能否用钢模成形有关键性影响;碳化硼氢化锆坯体的相对密度随碳化硼含量的增加而略有降低,随成形压力的增加而明显增加;碳化硼微粉严重阻碍了碳化硼锆合金的烧结,即使碳化硼的含量仅为0.49%（质量分数）,芯块的相对密度也会下降18%;提高烧结温度和增加成形压力对芯块的致密化有明显促进作用。B4C micro powders and zircaloy-2 hydride powder were used as starting material,and the green body was formed by conventional die pressing under pressure of 200 ~ 500MPa.The annular green body was dehydrogenated and then sintered at 1 100 ~ 1 300℃ for an hour.The microstructure of green body was observed by SEM,the effects of forming pressure and B4C content on the relative density of green body and sintered body were studied.The results show that the particle size of B4C plays a decisive role to determine whether the mixture can be formed by die pressing.The relative density of the green body decreases slightly with the increasing of B 4 C content,and increases rapidly with the increasing of the forming pressure.Small particle B4C powder hinders the sintering process,even 0.49wt% B4C content leads the relative density of sintered body decreasing by 18%.Raising the sintering temperature and increasing the forming pressure can be helpful for the densification of sintered body.

关 键 词：钢模成形 锆合金 中空芯块 碳化硼 可燃毒物 

分 类 号：TF046.4[冶金工程—冶金物理化学]