Advance in investigation on mechanical properties of B4C-SiC composite ceramics
B4C-SiC composite ceramics combine the properties of boron carbide(B4C)and silicon carbide(SiC)and have good physical and mechanical properties.Compared with monolithic B4C ceramics,B4C-SiC composite ceramics have improved fracture toughness.Compared with monolithic SiC ceramics,B4C-SiC composite ceramics possess increased hardness.B4C-SiC composite ceramics are expected to replace monolithic B4C ceramics and monolithic SiC ceramics to be widely used in engineering fields.The mechanical properties of B4C-SiC composite ceramics are related to the particle dispersion uniformity of B4C-SiC composite powders.Meanwhile,the mechanic-al properties of B4C-SiC composite ceramics are also influenced by their microstructure and phase composition.In order to reduce the sintering temperature of B4C-SiC composite ceramics,sintering additives are often added to the raw materials.The commonly used sintering additives include carbon,oxides,borides,carbides,metallic elements,and non-metallic elements(excluding carbon).The mechanisms by which different sintering additives promote the sintering of B4C-SiC composite ceramics vary.At the same time,these sintering additives affect the microstructure of B4C-SiC composite ceramics,which in turn affects their mechanical properties.Based on the research results of mechanical properties of B4C-SiC composite ceramics in recent years,the influencing factors of mechanical proper-ties of B4C-SiC composite ceramics are summarized in this review from the aspects of B4C-SiC composite powders,microstructure,phase composition,and sintering additives,so as to provide a basis for the design and investigation of B4C-SiC composite ceramics.
NETL
NSTL
万方数据
