无机材料学报2026，Vol.41Issue(2)：217-224,8.DOI:10.15541/jim20250209
晶粒尺寸对常压固相烧结SiC陶瓷断裂强度Weibull分布的影响
Influence of Grain Size on Weibull Distribution of Fracture Strength in Atmospheric-pressure Solid-phase Sintered SiC Ceramics
摘要
Abstract
Silicon carbide(SiC)ceramics have found extensive application in strategic fields,such as semiconductor technology,nuclear energy,aerospace engineering,and marine engineering,due to their remarkable properties,which encompass excellent mechanical properties,resistance to high-temperature creep,acid and alkali corrosion,and high thermal conductivity.However,the fracture strength of these brittle ceramic materials typically exhibits significant discreteness,which adversely affects reliability and limits their wider application as engineering structural materials.In this work,reliability of fracture strength in solid-state sintered silicon carbide(SSiC)ceramics was enhanced through regulation of grain size.The influence of grain size on mechanical properties,Weibull distribution of fracture strength,and crack extension resistance curve(R-curve)characteristics of SSiC ceramics was systematically evaluated.Reliability regulatory mechanism for fracture strength of SSiC ceramics was analyzed.The results indicated that,with an increase in sintering temperature from 2100℃to 2200℃,average grain size of SSiC ceramics increased from 3.01 µm to 8.45 µm,while coefficient of grain size distribution uniformity dropped from 0.70 to 0.62.As the average grain size was reduced from 8.45 µm to 3.01 µm,Weibull modulus of fracture strength for SSiC ceramics increased gradually from 8.5 to 12.2,representing a 44%increment.This clearly indicates the positive impact of grain refinement on reliability of fracture strength.Enhancement in Weibull modulus of fracture strength as a result of grain refinement can primarily be attributed to high-density grain boundary network,which effectively mitigates stress concentration via crack bifurcation and bridging mechanisms.Additionally,uniformity of grain distribution and reduced defect size contribute to an elevated energy threshold for crack propagation,leading to an ascending R-curve behavior.This work achieves a significant improvement in the fracture strength reliability of SiC ceramics through regulating grain size,which is expected to promote the wider engineering application of SiC ceramic materials.关键词
碳化硅陶瓷/晶粒尺寸/可靠性/Weibull模数/缺陷控制Key words
silicon carbide ceramic/grain size/reliability/Weibull modulus/defect control分类
化学化工引用本文复制引用
曹娟,吴西士,刘泽华,裴兵兵,韩建燊,刘欢,杨亦天,吴海波,黄政仁..晶粒尺寸对常压固相烧结SiC陶瓷断裂强度Weibull分布的影响[J].无机材料学报,2026,41(2):217-224,8.基金项目
国家重点研发计划(2022YFB3706200) （2022YFB3706200）
国家自然科学基金(U23A20563)National Key R&D Program of China(2022YFB3706200) （U23A20563）
National Natural Science Foundation of China(U23A20563) （U23A20563）
