Material data

With our “I-330” and “I-420” borosilicate glasses you have the right glass for every application.
For your information, here is the chemical composition of our TGI borosilicate glass I-330:
  • 80 by wt. SiO2
  • 13 by wt. B2O3
  • 4 by wt. Na2O3
  • 2 by wt. Al2O3
  • 1 by wt. K2O

Chemical properties:
  • Water resistance tested to DIN ISO 719 (at 98 °C): HGB 1 with a typical consumption of 0.04 ml hydrochloric acid [c(HCl) = 0.01 mol/l] per one gram glass grit
  • Water resistance tested to DIN ISO 720 (at 121 °C): HGA 1 with a typical consumption of 0.04 ml hydrochloric acid [c(HCl) = 0.02 mol/l] per one gram glass grit
  • Alkali resistance tested to DIN ISO 695: class A2 with a typical mass loss of 150 mg/dm2
  • Acid resistance tested to DIN 12 116: class 1
  • Acid resistance tested to DIN ISO 1776 with a typical alkali delivery of 50 mg Na2O/dm2

Physical properties:
  • Mean linear thermal expansion:
    α (20 °C ... 300 °C) = 3,3 ± 0,1 x 10–6 K–1
  • Density at 20 °C: ρ = 2,23 g/cm³
  • Mean thermal conductivity (20 °C ... 100 °C):
    λ = 1,2 W m–1 K–1
  • Working point:
    ϑf1 = 1250 °C at a viscosity of ηf1 = 104 dPa · s
  • Littleton/Softening point:
    ϑf2 = 815 °C at a viscosity of ηf2 = 107,6 dPa · s
  • Annealing point:
    ϑf3 = 560 °C at a viscosity of ηf3 = 1013 dPa · s
  • Strain point:
    ϑf4 = 510 °C at a viscosity ofηf4 = 1014,7 dPa · s
  • Transformation temperature: tg = 530 °C
  • Maximum permitted usage temperature: 500 °C
  • Modulus of elasticity: E = 64 GPa
For your information, here is the chemical composition of our TGI borosilicate glass I-420:
  • 77 by wt. SiO2
  • 11 by wt. B2O3
  • 5 by wt. Na2O
  • 5 by wt. Al2O3
  • 1 by wt. K2O
  • 1 by wt. ZrO2

 

Chemical properties:

  • Water resistance tested to DIN ISO 719 (at 98 °C): HGB 1 with a typical consumption of 0.04 ml hydrochloric acid [c(HCl) = 0.01 mol/l] per one gram glass grit
  • Water resistance tested to DIN ISO 720 (at 121 °C): HGA 1 with a typical consumption of 0.04 ml hydrochloric acid [c(HCl) = 0.02 mol/l] per one gram glass grit
  • Alkali resistance tested to DIN ISO 695: class A2 with a typical mass loss of 150 mg/dm2
  • Acid resistance tested to DIN 12 116: class 1
  • Acid resistance tested to DIN ISO 1776 with a typical alkali delivery of 50 mg Na2O/dm2

 

Physical properties:

  • Mean linear thermal expansion:
    α (20 °C...300 °C) = 4,2 ± 0,1x10-6 K-1
  • Density at 20 °C: ρ = 2,28g/cm3
  • Mean thermal conductivity
    (20 °C... 100 °C) λ = 1,4 W m-1 K-1
  • Working point:
    ϑf1 = 1225 °C at a viscosity of ηf1 = 104 dPa • s
  • Littleton/Softening point:
    ϑf2 = 810 °C at a viscosity of ηf2 = 107,6 dPa • s
  • Annealing point:
    ϑf3 = 580 °C at a viscosity of ηf3 = 1013 dPa • s
  • Strain point:
    ϑf4 = 520 °C at a viscosity of ηf4 = 1014,7 dPa • s
  • Transformation temperature:
    tg = 560 °C
  • Maximum permitted usage temperature:
    500 °C für den Werkstoff (280°C für Schaugläser im vorgespannten Zustand)
  • Modulus of elasticity:
    E = 66 GPa
  • Poisson number:
    μ= 0,20 • 103 N/mm2

Electrical properties:

  • Volume resistivity
    at 25°C = 6.6 x 1013 Ω cm
    at 300°C = 1.4 x 106 Ω cm
  • Dielectric properties at 25°C and 1 MHz:
    Dielectric constant εr = 4.6
    Loss factor tan δ = 1.4 x 10-2


Optical properties:

  • Refractive index
    λ = 587.6 nm nD = 1.4816
    λ = 480.0 nm nF = 1.4869
    λ = 546.0 nm nE = 1.4831
    λ = 644.0 nm nC = 1.4802