氧化锆含量对SiO_2-MgO-Al_2O_3-K_2O-ZrO_2-F玻璃析晶性能的影响(英文)

EFFECT OF ZrO_2 CONTENTS ON THE CRYSTALLINE CHARACTERISTIC OF SiO_2-MgO- Al_2O_3-K_2O-ZrO_2-F GLASS

用扫描电子显微镜、X射线衍射和电子探针等技术研究了氧化锆含量对 SiO2 MgO Al2O3 K2O ZrO2 F系玻璃析晶性能的影响。结果表明:在所研究的玻璃体系中,氧化锆的加入促进了玻璃在低温下的分相与析晶。在分相区域内,针状云母晶体析出。云母晶体的生长受到分相区的限制,其形状和分相区域相一致。当玻璃中引入质量分数为 3.0%的氧化锆后,在热处理过程中首先析出单斜 ZrO2和四方ZrO2,表明氧化锆在此玻璃体系中的固溶度小于3.0%。氧化锆的析出促进了云母晶体的形成,枝状云母晶体依靠氧化锆异质外延生长,相互交错形成环形的显微组织。

The effect of ZrO_(2 )contents on crystalline process and characteristic in the SiO_2-MgO-Al_2O_3-K_2O- ZrO_2-F glass during thermal treatment was investigated by using SEM, XRD and EPMA. Results show that the adding of ZrO_2 in the glass promotes the forming of phase-separation and crystallization at the lower temperatures. The growth of the mica crystals was confined by the regions of phase-separation, and the needle-like mica crystals with similar shape as the phase-separation are observed. It is found that m-ZrO_2 and t-ZrO_2 are homogeneously precipitated after heated to 800 ℃ in the glass with 3.0% (in mass fraction) of ZrO_2, which suggested that the solid solubility of ZrO_2 is less than 3.0% in the glass. The precipitation of ZrO_(2 ) crystals is in favor of the crystallization of mica phases and the dendrite-like mica crystals grow through epitaxial processes on ZrO_(2 ) particles, forming the ring-shaped microstructures.