单质硅粉对堇青石-莫来石匣钵孔结构和抗侵蚀性能的影响  

Effect of Silicon Powder on Pore Structure and Corrosion Resistance of Cordierite-Mullite Saggar

作　　者：刘伟正 李亚伟[1,2] 徐义彪[1,2] LIU Weizheng;LI Yawei;XU Yibiao(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China;National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学,耐火材料与冶金国家重点实验室,武汉430081 [2]武汉科技大学,国家高温材料与炉衬技术省级联合工程研究中心,武汉430081

出　　处：《硅酸盐通报》2025年第3期1152-1162,共11页Bulletin of the Chinese Ceramic Society

基　　金：国家重点研发计划(2019YFC1904900);青海省科技成果转化专项项目(2023-GX-102)。

摘　　要：为了提高锂离子电池三元正极材料(LiNixCoyMn1-x-yO_(2),LNCM)工业中堇青石-莫来石匣钵的使用寿命,将单质Si粉引入到堇青石-莫来石试样中,研究了Si粉含量对试样烧结性能、孔径分布、力学性能、热震稳定性及抗LNCM侵蚀性能的影响。结果表明:Si粉含量由0%(质量分数,下同)增加至5%,高温下试样中液相增加,促进了物质传输及烧结过程,骨料与基质间结合增强,试样显气孔率及孔径降低,强度及抗热震性能提高;增加Si粉含量至7%,基质因液相生成过多发生较大收缩,骨料与基质间隙增大,试样强度及抗热震性能降低。LNCM与试样侵蚀反应主要生成LiAlSiO_(4)和(Mg,Ni,Co,Mn)Al_(2)O_(4)复合尖晶石,其中生成LiAlSiO_(4)的侵蚀反应伴随约32%的体积膨胀,导致试样开裂及剥落。Si粉含量由0%增加至5%,试样因显气孔率及孔径降低,LNCM渗透通道减少,抗侵蚀性能显著提高;增加Si粉含量至7%,虽然试样孔径增大,但基质形成连续致密结构,抗侵蚀性能依然略有改善。综合来看,单质Si粉引入量为5%的试样性能最佳:显气孔率为23.6%,边缘及中心平均孔径分别为1.5和1.7μm,常温抗折强度及3次热冲击后残余强度保持率分别为15.6 MPa和86.1%,侵蚀层平均厚度为685μm。To extend the service life of cordierite-mullite saggar in the lithium-ion battery ternary cathode material(LiNix Coy Mn1-x-y O_(2),LNCM)industry,silicon powder was introduced into cordierite-mullite samples and the effect of silicon powder content on the sintering performance,pore size distribution,mechanical properties,thermal shock stability,and corrosion resistance against LNCM was investigated.The results indicate that when the silicon powder content increases from 0%(mass fraction,the same below)to 5%,the liquid phase in the samples increases at high temperatures,promoting mass transport and the sintering process.The bonding between the aggregate and the matrix is enhanced,leading to a decrease in apparent porosity and pore size,while the strength and thermal shock resistance are improved.When the content of silicon powder increases to 7%,the interstices between the aggregate and the matrix are increased because of the significant shrinkage of the matrix,due to excessive liquid phase formation.Hence,the strength and the thermal shock resistance of samples are decreased.LiAlSiO_(4)and(Mg,Ni,Co,Mn)Al_(2)O_(4)composite spinel are generated in the corrosion reaction between the LNCM and sample.The formation of LiAlSiO_(4)is accompanied by approximately 32%volumetric expansion,leading to cracking and spalling of samples.As the silicon powder content increases from 0%to 5%,the migration channel for LNCM is decreased due to the reduction in apparent porosity and pore size,significantly improving the corrosion resistance.When the content of silicon powder increases to 7%,the pore size of samples increases but the corrosion resistance is still improved slightly due to the formation of a continuous dense structure in the matrix.Overall,the sample with 5%silicon powder exhibits the best performance:the apparent porosity is 23.6%,with average pore sizes of 1.5 and 1.7μm at the edge and center,respectively.The cold modulus of rapture and residual strength ratio after three times thermal shocks are 15.6 MPa and 86.1%,re

关 键 词：三元正极材料 堇青石-莫来石 SI粉 孔径分布 抗侵蚀性能 

分 类 号：TQ175[化学工程—硅酸盐工业]