Studies of the Glass-formation Range of Silicate Systems : Investigations on the Glass-formation Range, 2
Studies of the Glass-formation Range of Silicate Systems : Investigations on the Glass-formation Range, 2
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硅酸盐体系的玻璃形成范围的研究：玻璃形成范围的研究，2
DOI：
10.2109/jcersj1950.71.816_215
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发表时间：
1963
期刊：
影响因子：
--
通讯作者：
T. Yamazaki
中科院分区：
文献类型：
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作者：
M. Imaoka;T. Yamazaki
根据先前的报告“硼酸盐系统的玻璃形成范围的研究”（This Journal，69，282（1961）），我们研究了硅酸盐系统的玻璃形成范围。虽然硅酸盐玻璃的应用由来已久，但对硅酸盐系统的玻璃形成范围还没有进行充分系统的研究。在由纯铂或含20%铑的铂制成的坩埚中，在1400° C至1750°C的温度下熔化材料。除了SiO2之外，所使用的氧化物是16种a族元素的氧化物，即Li、Na、K、Be、Mg、Ca、Sr、Ba、Al、La、Ti、Zr、Th、Nb、Ta和W。二元硅酸盐系统的玻璃形成范围示于表1中。这些范围在某些方面不同于硼酸盐体系的范围。例如，La-硅酸盐系统没有玻璃化范围，而Mg-硅酸盐系统具有比硼酸盐更宽的玻璃形成范围。组分离子是作为改性剂还是作为网络形成剂进入玻璃结构取决于玻璃形成剂的酸度和组分离子的电负性。然而，在硅酸盐系统中，玻璃形成的实际范围等于玻璃形成范围与不混溶范围之间的差。如果后者等于前者或稍宽，则玻璃化区消失。三元系玻璃形成区如图1-34所示。所研究的系统总数达到约一百个。实验结果表明，实际的玻璃形成范围与“玻璃形成条件”（This Glassnaj，67，364（1959））预期的范围（图中阴影区域）一致。在这些体系中，含有TiO 2的体系（参见图12和13）与相应的硼酸盐体系显著不同。在硼酸盐体系中，玻璃形成范围在SiO2-D线的右侧扩展（参见图11）。图10），因此估计Ti 4+的配位数为6。(In为了使Ti ~（4+）离子以六配位作为网络形成剂，还必须存在二价的改性剂，因此，在SiO_2-D线左边的区域中不可能形成玻璃。而在硅酸盐体系中，缺少SiO2-D的极限线。因此，可以得出结论，Ti 4+离子以及Si 4+离子采取4-配位。含TiO 2系统的玻璃形成范围显示在图1A和1B的阴影区域中。与硼酸盐体系相比，含WO 3的硅酸盐体系具有非常窄的玻璃形成范围。B_2O_3-WO_3-碱金属氧化物系统的玻璃化范围有两个脚，但硅酸盐系统，我们认为，缺乏左脚。此外，还认为在硼酸盐体系中，左脚部分由WO_3和碱金属硼酸盐组成，而在硅酸盐体系中，左脚部分变得不互溶.根据二元体系的失透情况，La_2O_3体系属于C型三元体系，其玻璃形成范围比硼酸盐体系窄. SiO2-Al 2 O3-La 2 O3系统的玻璃化范围（参见图29）与相应的硼酸盐体系的结果一致，但不混溶区的极限线kl低于硼酸盐体系的极限线kl，因此前者的玻璃形成区比后者窄。其他硅酸镧系统类似。在含有ThO_2或Al_2O_3的C型三元体系中，它们在相应的硼酸盐体系中具有玻璃化范围，我们发现只有SiO_2处于玻璃态
Following a previous report “Studies of the Glass-formation Range of Borate Systems” (This Journal, 69, 282 (1961)), we studied the glass-formation range of silicate systems. Although silicate glasses have long been used, sufficient systematic studies of the glassformation ranges of silicate systems have not yet been made.In this experiment, 1/80 mole (about 1g.) of materials were melted in crucibles made of pure platinum or platinum containing 20% rhodium at temperatures from 1400° to 1750°C. The oxides used besides SiO2 were 16 kinds of the oxides of a-group elements namely Li, Na, K, Be, Mg, Ca, Sr, Ba, Al, La, Ti, Zr, Th, Nb, Ta and W.The glass-formation ranges of binary silicate systems are shown in Table 1. These ranges differ in some points from those of borate systems. For instance, the La-silicate system has no vitrified range, while the Mg-silicate system has a wider glass-formation range than the borate. Whether a component ion enters into the glass structure as a modifier or as a network-former depends on the acidity of the glass-former and on the electronegativity of the component ion. In silicate systems, however, the actual range of glass-formation equals the difference between the glass-formation range and the immiscible range. If the latter is equal to the former or somewhat wider, the vitrified range will disappear.The glass-formation ranges of ternary systems are shown in Fig. 1-34. The whole number of the studied systems reached about one hundred. The Experimental results show that the actual glass-formation ranges agree with the range (hatched areas in the figures) to be expected from the “Conditions of Glass-formation” (This Journaj, 67, 364 (1959)). Among these systems, the systems containing TiO2 (cf. Figs. 12 and 13) are remarkably different from the corresponding borate systems. In the borate systems, a glass-fromation range spreads on the right side of the SiO2-D line (cf. Fig. 10), and therefore it has been estimated that the co-ordination number of Ti4+ is 6. (In order for the Ti4+ ion to take 6-co-ordination as a network-former, the modifier of divalency must also be present, therefor, in the area on the left of the SiO2-D line glass-formation is impossible.) However, in the silicate system the limited line of SiO2-D is lacking. Consequently, it is concluded that the Ti4+ ion as well as the Si4+ ion takes the 4-co-ordination. The glass-formation range of the TiO2-containing systems are shown in the hatched areas of Figs. 12 and 13, which are limited by the AD line.The WO3-containing silicate systems have a remarkably narrow glass-formation range compared with borate systems. The vitrified range of the B2O3-WO3-alkali oxide system has two feet, but the silicate system, we suppose, lacks the left foot. Moreover, it is considered that the left foot consists of WO3 and alkali borate in borate systems, but that this part becomes immiscible in silicate systems.According to the devitrification of the binary system, La2O3 systems are classified as C-type ternary systems, and their glass-formation ranges are narrower than those of borate systems. The vitrified range of the SiO2-Al2O3-La2O3 system (cf. Fig. 29) agrees with that of the corresponding borate system, but the limiting line, kl, of the immiscible range is lower than that of the borate and, accordingly the glass-formation range of the former is narrower than that of the latter. Other La-silicate systems are similar. Among the C-type ternary systems containing ThO2 or Al2O3, which have vitrified ranges in case of the corresponding borate systems, we found the glassy state only in the SiO2