The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were inves...The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were investigated.The purity of obtained CM_2A_8 and C_2M_2A_(14) ceramics reaches 98.1 wt%and 97.5 wt%,respectively.Their microstructure is dense with few observable pores,and their grain size is about a few dozen microns.For their physical properties,the average apparent porosity of CM_2A_8 and C_2M_2A_(14) ceramics is 0.18% and 0.13%,and their average bulk density is 3.66 g/cm^3 and 3.71 g/cm^3,respectively.The relative density of CM_2A_8 ceramic is 98.12%and that of C_2M_2A_(14)ceramic is 98.67%.The thermal expansivity(50–1400℃)of CM_2A_8 and C_2M_2A_(14) ceramics is 9.24×10^(–6)K^(–1) and 8.92×10^(–6)K^(–1),respectively.The thermal conductivity of CM_2A_8 and C_2M_2A_(14) ceramic is 21.32 W/(m·K)and 23.25 W/(m·K)at 25℃and 18.76 W/(m·K)and 19.42 W/(m·K)as temperature rises to 350℃,respectively.In addition,the mechanical properties are also achieved.For CM_2A_8 ceramic,the flexural strength is 248 MPa,the fracture toughness is 2.17 MPa·m^(1/2),and the Vickers hardness is 12.26 GPa.For C_2M_2A_(14) ceramic,the flexural strength is 262 MPa,the fracture toughness is 2.23 MPa·m^(1/2),and the Vickers hardness is 12.95 GPa.展开更多
基金supported by the National Natural Science Foundation of China (No. 51572019)the National Science Fund for Excellent Young Scholars of China (No. 51522402)
文摘The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were investigated.The purity of obtained CM_2A_8 and C_2M_2A_(14) ceramics reaches 98.1 wt%and 97.5 wt%,respectively.Their microstructure is dense with few observable pores,and their grain size is about a few dozen microns.For their physical properties,the average apparent porosity of CM_2A_8 and C_2M_2A_(14) ceramics is 0.18% and 0.13%,and their average bulk density is 3.66 g/cm^3 and 3.71 g/cm^3,respectively.The relative density of CM_2A_8 ceramic is 98.12%and that of C_2M_2A_(14)ceramic is 98.67%.The thermal expansivity(50–1400℃)of CM_2A_8 and C_2M_2A_(14) ceramics is 9.24×10^(–6)K^(–1) and 8.92×10^(–6)K^(–1),respectively.The thermal conductivity of CM_2A_8 and C_2M_2A_(14) ceramic is 21.32 W/(m·K)and 23.25 W/(m·K)at 25℃and 18.76 W/(m·K)and 19.42 W/(m·K)as temperature rises to 350℃,respectively.In addition,the mechanical properties are also achieved.For CM_2A_8 ceramic,the flexural strength is 248 MPa,the fracture toughness is 2.17 MPa·m^(1/2),and the Vickers hardness is 12.26 GPa.For C_2M_2A_(14) ceramic,the flexural strength is 262 MPa,the fracture toughness is 2.23 MPa·m^(1/2),and the Vickers hardness is 12.95 GPa.
