研究了在β10－Sialon（Si5.23Al0.77O0.77N7.23）中加入7.26Wt％Nd-黄长石固溶体（Nd2Si2AlO4N3）组份的反应过程和致密化行为．烧结过程中，稀土元素先进入α－Sialon；随温度的升高，稀土元素存在于晶界玻璃相中，并在退火过程中以黄长石相析出．对热压及经退火处理的样品，研究了其在1000～1400℃的氧化行为．1000℃氧化时，作为晶界相的黄长石固溶体并不会导致样品开裂．但在更高温度氧化时，氧化后的表面存在择优取向的A－Nd2Si2O7晶粒，且由于Nd离子的表面偏析使表面氧化层软化而形成气泡．
The formation behavior of the composition of β10-Sialon(Si5.23Al0.77O0.77N7.23) plus 7.26wt% Nd-melilite solid solution (Nd2Si2AlO4N3) prepared by
pressureless sintering was studied. Nd ions in the composition enter α-sialon at low temperature, dissolve in the liquid phase of the material with
temperature increasing. Melilite solid solution can be formed as a grain boundary phase of the ceramics by heat-teatment at 1550℃ for 24h. The oxidation behavior
of the hot-pressed and post-sintered samples was also investigated in the range of 1000～400℃. The melilite solid solution doesn’t caues severe cracking
of the material in oxidation at 1000℃ At high temperature, the oxidized surface of the sample contains preferentially oriented A-Nd2Si2O7 grains and bubbles,
which are formed because of the decrease of the silicate viscosity, incurred by the accumulation of Nd ions to the surface.
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