Abstract
An experimental study for fabrication, physical, FTIR spectroscopy, ultrasonic waves, and mechanical properties of quaternary B
2
O
3
–Bi
2
O
3
–NaF–ZrO
2
glasses was introduced. The fabricated glasses have the chemical formula 65B
2
O
3
–25NaF–(10-
x
)Bi
2
O
3
–
x
ZrO
2
;
x
= 0 (Zr0), 2 (Zr2), 4 (Zr4), 5 (Zr5), and 6 (Zr6) mol% and produced via the melt quenching process. The longitudinal
V
L
and shear
V
S
velocities were measured using ultrasonic flaw detector. FTIR spectra were recorded in the wavenumber range 400–1550 cm
−1
. The density of the fabricated glasses reduces linearly from 3400 ± 6 (kg/m
3
) for Zr0 sample with free ZrO
2
to 3099 ± 4 (kg/m
3
) for Zr6 sample with highest content of ZrO
2
. The oxygen packing density (OPD) rises from 74,742 to 82,980 kg atom/m
3
when increasing content of ZrO
2
from 0 to 6 mol%, respectively. The number of N3 was increased which the number of N4 decreased with ZrO
2
concentration which confirms that the decreasing formation of BO
4
units with ZrO
2
content. Both
V
L
and
V
S
are persistently increasing for all range of the studied samples; such a behavior is ascribed to increments in number of strong Ø’s units. The insertion of ZrO
2
in glasses network leads to improve their elastic moduli. Higher values of Debye temperature (
θ
D
) are found with increasing ZrO
2
content that means higher thermal energy needed for excitation the corresponding vibrational mode. Makishima–Mackenzie values of Young (
Y
M
) and bulk (
B
M
) moduli were in good agreement with the experimental results. Therefore, the increasing trends of
Y
M
and B
M
are similar to those of Young (Y) and bulk (B) moduli assuring the effect of [ZrO
6
]
2−
on introducing strengthened bonds into borate lattice. In addition, the microhardness (
H
v
) was found to increase with ZrO
2
content; therefore, the glass system gets harder and stiffer.