Premium
Nitridation Effect on Properties of Stannous‐Lead Phosphate Glasses
Author(s) -
Yung Hsiwen,
Shih P. Y.,
Liu H. S.,
Chin T. S.
Publication year - 1997
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.1151-2916.1997.tb03110.x
Subject(s) - dissolution , nitrogen , phosphate glass , inorganic chemistry , nitriding , softening point , x ray photoelectron spectroscopy , anhydrous , glass transition , phosphate , oxide , alkali metal , materials science , fourier transform infrared spectroscopy , chemistry , analytical chemistry (journal) , metallurgy , chemical engineering , environmental chemistry , organic chemistry , polymer chemistry , engineering , composite material , polymer
Stannous‐lead phosphorus oxynitride (Sn‐Pb‐P‐O‐N) glasses were prepared by remelting under an anhydrous ammonia atmosphere. Glasses that contained up to ∼4.2 wt% (9 at.%) of nitrogen were obtained. The rate of nitrogen dissolution was studied as a function of remelting time (3–66 h) and temperature (400°–600°C). The onset nitridation temperature was extrapolated to be 315°C; higher nitridation temperatures accelerated nitrogen dissolution. Nitridation of the stannous‐lead oxyphosphate (Sn‐Pb‐P‐O) glasses decreased the dissolution rate in water and the thermal expansion coefficient; however, it increased the dilatometric softening temperature, the glass‐transition temperature, the microhardness, and the density. The chemical durability of the nitrided glasses increased more than four orders of magnitude with 3.0 wt% of nitrogen content. An increase in the lead oxide content in the stannous phosphate glasses also improved the chemical durability. Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy suggested that nitrogen replaces the terminating hydroxyl ion and the bridging and nonbridging oxygen atoms in the PO4 tetrahedra to form the functional groups –NH<, –N<, and –N=, which leads to enhanced crosslinking of the glass network. Quantitative results regarding these bondings have been given.