Borosilicate Glass Material Properties
Borosilicate Glass (SiO2 and B2O3), has a very low coefficient of thermal expansion making it more resistant to thermal shock than any other common glass. It also has very high electrical resistivity and dielectric strength, high chemical stability, withstands high applied torque loads and is visible to near Infrared transmission.
Applications for precision balls include: valves, pumps, insulators, calibration, spacer
Borosilicate Glass
PHYSICAL PROPERTIES | |
---|---|
composition | SiO2 65-85% |
B2O3 8-15% | |
Na2O 3-9% | |
Al2O3 1-5% | |
K2O max 2% | |
density | 2.23 g/cm3 |
max working temperature | 300 – 400°C |
THERMAL PROPERTIES | |
melting point | 1252°C |
softening temperature | 821°C |
thermal conductivity | 1.15 W/(m·K) |
shock resistance | 300°C |
MECHANICAL PROPERTIES | |
hardness | Mohs 6 |
Knoop 420 – 520 | |
Poisson’s ratio | 0.20 |
Young’s modulus | 64 GPa |
compressive strength | 9327 kg/cm2 |
tensile strength | 832 kg/cm2 |
ELECTRICAL PROPERTIES | |
volume resistivity | >10^15 Ω·m |
OPTICAL PROPERTIES | |
refractive index | 1.471 nm |
MAGNETIC PROPERTIES | |
relative magnetic permeability | diamagnetic <-1 |