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采用ＸＲＤ分析了单斜钡长石晶种对六方钡长石向单斜钡长石转变的影响，并根据ＪＭＡ方程讨论了相变速率．实验结果表明，在ＢＡＳ凝胶玻璃中加入单斜钡长石作为晶种，可以在晶化过程中促进六方相向单斜相转变，获得主晶相为单斜钡长石的ＢＡＳ玻璃陶瓷．当晶化温度大于１２００℃，晶种加入量大于５ｗｔ％时，能明显提高相变速率．晶种促进相变是晶种在其周围的六方钡长石晶粒表面诱发生成单斜相晶核并长大的过程．在ＳｉＣ晶须增强ＢＡＳ玻璃陶瓷复合材料中，由于ＳｉＣ晶须减少了晶种与六方相晶粒间的接触面积，因而减弱了晶种促进相变的效果．
The influence of monoclinic barite feldspar on the transformation of hexagonal barite to monoclinic celite was analyzed by XRD. The phase transformation rate was discussed according to the JMA equation. The experimental results show that adding monoclinic cesium feldspar into BAS gel glass can promote the transformation of hexagonal to monoclinic phase during the crystallization process and obtain the BAS glass ceramic with monoclinic cristobalite as the main crystal phase. When the crystallization temperature is higher than 1200 ℃, the addition of seed is more than 5wt%, the phase transformation rate can be obviously improved. Seed-induced phase transition is the process by which seed crystals induce monoclinic phase nuclei on the surface of hexagonal celsian grains around them and grow up. In SiC whisker reinforced BAS glass ceramic composites, SiC whiskers reduce the contact area between the seed and the hexagonal grains, thus weakening the effect of seed crystal promoting the phase transition.