The role of aluminium in the durability of alumino- borosilicate glasses
The role of aluminium in the durability of alumino- borosilicate glasses
复制标题
铝在铝硼硅酸盐玻璃耐久性中的作用
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
P. Barboux
中科院分区：
文献类型：
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作者：
A. Ledieu;F. Devreux;P. Barboux
随着铝含量的增加，钠铝硼硅酸盐玻璃在各种水溶液中被腐蚀。研究了铝含量和浸出液性质对浸出率的影响。主要系列的实验已进行了在恒定的pH值为8.5的玻璃含有0，1，2，5和10摩尔%的Al 2 O 3取代二氧化硅。铝的存在减缓了腐蚀动力学并降低了溶液中的硅浓度，但强烈地增加了腐蚀的最终程度（通过可溶性元素硼和钠的损失来测量）。已经进行了两个互补的实验来理解这种意想不到的行为。首先，在铝螯合剂的存在下，腐蚀了含铝和不含铝的两种玻璃。第二，同样的玻璃在蒸馏水中被腐蚀，由于钠的释放，pH值漂移到9.5。铝对最终腐蚀程度的负面影响可以通过以下附加效应来解释：（i）将部分溶解的硅和铝原子捕获在不溶性络合物中，这使得它们无法用于改变的表面层的重组，以及（ii）溶解速率的降低，这延迟了该层的钝化。
Sodium alumino-borosilicate glasses with increasing aluminium contents have been corroded in various aqueous solutions. The influence of the aluminium content and that of the nature of the leaching solution have been studied. The main series of experiments have been performed at the constant pH of 8.5 on glasses containing 0, 1, 2, 5 and 10 mol% of Al 2 O 3 substituted for silica. The presence of aluminium slows down the corrosion kinetics and decreases the silicon concentration in solution, but strongly increases the final extent of corrosion (as measured by the loss of soluble elements, boron and sodium). Two complementary experiments have been performed to understand this unexpected behaviour. First, two glasses with and without aluminium have been corroded in the presence of an aluminium chelating reagent. Second, the same glasses have been corroded in distilled water, where the pH drifts up to 9.5 due to the release of sodium. The negative influence of aluminium on the final degree of corrosion is explained by the additional effects of (i) the trapping of a part of the dissolved silicon and aluminium atoms in insoluble complexes, which makes them unavailable for the restructuring of the altered surface layer, and (ii) the decrease of the dissolution rates which delays the passivation of the layer.