Corning® Pyrex® 7740 Glass

Glass Type: Borosilicate


Pyrex® 7740 is Corning’s trade name borosilicate glass. It has a low coefficient of thermal expansion and good heat shock resistance. Pyrex® can be used as a substitute for SCHOTT Borofloat® in most cases. SGP can CNC mill, drill, cut, lap, and polish Pyrex® to any dimension, shape or surface finish.

Thermal PropertiesMechanical Properties
Thermal Coefficient of Expansion(0/300°C): 32.5 X 10-7/°CDensity2.23 g/cm3 (at 20°C/68°F)
Annealing Point560°C/1040° FKnoop Hardness448 kg/mm2
Softening Point821°C/1509.8°FYoung’s Modulus64 G pa
Strain Point510°C / 950° FPoisson’s Ratio0.20
Chemical PropertiesElectrical Properties
Hydrolytic Resistanceclass 1Dielectric ConstantE=4.61 MHz <5>R.T.
Acid Resistanceclass 1Resistivity8 X 1010 ohm/cm @R.T.
Alkali Resistanceclass 2Dielectric Strength0.5 KV/mm
Optical Properties
Refractive Index1.473 (589.3 nm)