| 摘要 |
PROBLEM TO BE SOLVED: To obtain powdery magnesium silicide nitride of a high purity, being super fine particles, having a specified surface area and capable of being easily sintered by mixing powdery amorphous silicon nitride with powdery magnesium nitride in a specified ratio and heating the mixture to crystallize in a nitrogen- containing atmosphere. SOLUTION: Powdery magnesium silicide nitride is obtained by mixing powdery amorphous silicon nitride with powdery magnesium nitride to bring the atomic ratio of Si and Mg to (0.95-1.05):(1.05-0.95) and heating the mixture to crystallizing the temp. range of 1300-1600 deg.C in a nitrogen-containing atmosphere. The powdery magnesium silicide nitride contains >=95 wt.% of a magnesium silicide nitride phase expressed by the formula MgSiN2 and has 5-20 m<2> /g specific surface area. It is preferable to contain 0.2-5 wt.% of oxygen in the powdery silicide nitride, as sintering is brought to be excellent. The above mentioned amorphous powdery silicide nitride is obtained by a usual method, e.g. by heat- treating a reaction product of silicon tetrahalide with ammonia. |
