Premium
A New Low‐Brittleness Glass in the Soda‐Lime‐Silica Glass Family
Author(s) -
Sehgal Jeetendra,
Ito Setsuro
Publication year - 1998
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1998.tb02649.x
Subject(s) - brittleness , materials science , soda lime glass , composite material , soda lime , indentation , fracture toughness , borosilicate glass , lime , toughness , glass recycling , vickers hardness test , metallurgy , mineralogy , chemistry , microstructure
In the soda‐lime‐silica glass family, the effect of each constituent of the composition on the brittleness was first investigated. Vickers indentation was employed to estimate the brittleness (ratio of harness ( H ) to fracture toughness ( K c )) by measuring the C / a ratios (where C and a are the characteristic crack and indentation diagonal lengths, respectively). It was observed that a higher silica content and a lower lime content helped to lower the brittleness. Substitution of potash and magnesia for soda and calcia, respectively, was effective in lowering the brittleness. From these results, a higher molar volume was found to be a key factor for reducing the brittleness. A new low‐brittleness glass was then developed with a brittleness as low as 5.1 µm ‐1/2 as compared with the brittleness of 7.1 µm ‐1/2 for commercial soda‐lime‐silica glass. The crack initiation load ( P *), measured by the Vickers indentation method, for this new low‐brittleness glass was almost 10 times as high as P * of commercial soda‐lime‐silica glass. The new glass shows lower hardness and higher fracture toughness than the commercial soda‐lime‐silica glass.