The Effect of Storage on the Strength of Annealed and Toughened Clear White Plate Glass

摘要

The effect of storage on the strength of annealed and toughened clear white plate glass has been investigated using storage in atmospheric conditions, compared with storage in dry, carbon dioxide-free conditions over a five year period. Under all conditions a reduction in strength took place over an initial period up to 18 months. Thereafter, a considerable recovery took place. It is estimated that total recovery would take place in about eight years. The exposed toughened glasses showed a maximum reduction to 90% of the original value, the annealed specimens showing a greater percentage reduction as ageing is primarily an intrinsic property of the glass surface. The difference between the exposed specimens and those stored under dry carbon dioxide-free conditions for both annealed and toughened glasses was shown to be significant at the 2% level of probability. (Author)