Thermal Conductivity Of Silicon Nitride Ceramics

Silicon nitride si 3 n 4 ceramic properties.

Thermal conductivity of silicon nitride ceramics.

The theoretical thermal conductivity of silicon nitride crystals is 200 320 w m k. The bonding strength average atomic mass and anharmonic vibration of silicon nitride ceramics are similar to those of sic. Due to the reduction of lattice oxygen content the srbsn ceramics could. The thermal conductivity of sn1 was about 55 w mk at 323 k and decreased as the temperature increased reaching 45 w mk at 473 k.

Dense silicon nitride si 3 n 4 ceramics were prepared using y 2 o 3 and mgf 2 as sintering aids by spark plasma sintering sps at 1650 c for 5 min and post sintering annealing at 1900 c for 4 h. Silicon nitride si 3 n 4 composites containing carbon nanotubes cnts or graphene nanoplateles gnps are of great relevance in the electronic and aerospace industries where the search for new materials with enhanced and anisotropic thermal conductivity to work in harsh environments is a strategic guideline here we study thermal conduction in si 3 n 4 composites with different amounts of. Silicon nitride has the most versatile combination of mechanical thermal and electrical properties of any technical ceramic material. Hence si 3 n 4 is the most commercially important of the silicon nitrides when referring to the term silicon nitride.

The values of the thermal conductivity for the snn10 snn15 snn20 substrates were about 85 90 w mk at 323 k and they decreased at elevated temperature reaching about 70 75 w mk at 473 k. Because of the strong covalent nature of si n bond si 3 n 4 ceramics possess a lot of attractive properties such as high strength at room and elevated temperatures high hardness good resistance to corrosion thermal shock and oxidation and so on besides si 3 n 4 ceramics have gained a staunch reputation of high thermal conductivity since haggerty and lightfoot. Silicon nitride si3n4 with high thermal conductivity has emerged as one of the most promising substrate materials for the next generation power devices. Silicon nitride is a man made compound synthesized through several different chemical reaction methods.

Effects of mgf 2 contents on densification phase transformation microstructure mechanical properties and thermal conductivity of the si 3 n 4 ceramics before and after heat treatment were. It is a high performance technical ceramic that is extremely hard and has exceptional thermal shock and impact resistance. Silicon nitride is a chemical compound of the elements silicon and nitrogen. Si 3 n 4 is the most thermodynamically stable of the silicon nitrides.