CaO-Y_(2)O_(3)复合材料的制备及性能研究

Preparation and Properties of CaO-Y_(2)O_(3)Composites

分别以Y(NO_(3))_(3)·6H_(2)O、CaCO_(3)为钇源和钙源,以CO(NH_(2))2为燃料,采用低温自蔓延燃烧合成(LCS)法制备复合Y_(2)O_(3)包覆CaO粉体,合成粉体经煅烧、压制、干燥、烧结后制备出复合CaO-Y_(2)O_(3)材料,考察了钙钇摩尔比对复合材料结构及性能的影响。结果表明:所制备的复合粉体具有良好的包覆性。钙钇摩尔比为2∶1时材料物理性能最佳,其相对密度达到96.56%,显气孔率为1.32%,常温耐压强度为270.0 MPa,热震循环5次后试样残余强度保持率为88.39%,大气环境下21 d后的水化增重率为0.75%。

Using yttrium nitrate hexahydrate and calcium carbonate as yttrium and calcium sources,and urea as fuel,the Y_(2)O_(3)coating CaO powder were prepared by low temperature self-spreading combustion synthesis(LCS)method.The CaO-Y_(2)O_(3)composites were prepared by calcination,pressing,drying and sintering.The effects of the molar ratio of calcium to yttrium on the structure and properties of composites were investigated.The results show that the prepared Y_(2)O_(3)coating CaO powder has good coating property.When the molar ratio of calcium to yttrium is 2∶1,the physical properties of the material are the best,the relative density is 96.56%,the apparent porosity is 1.32%,the compressive strength at room temperature is 270.0 MPa,the residual strength retention rate of the sample after 5 thermal shock cycles is 88.39%,and the hydration weight gain rate of the sample after 21 d in the atmospheric environment is 0.75%.