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Thermal properties

Excellent temperature and thermal shock resistance

NEXTREMA® performs even when exposed to high temperatures or rapid temperature changes. Due to its excellent resistance to temperatures of up to 950 °C and thermal shocks NEXTREMA® is the ideal solution for high temperature applications where glass properties are beneficial.

Coefficient of linear thermal expansion (DIN ISO 51045-1, DIN ISO 7991)

In certain applications, the coefficient of mean linear thermal expansion and therefore the total change of length of a NEXTREMA® part within a specified temperature range is important to its function. The following mean coefficient values and the graph show the temperature dependency.

CTE in different temperature ranges

α (-50 °C; 100 °C) -0.8 – 0.6 x 10-6 K-1  
α (0 °C; 50 °C) -0.8 – 0.6 x 10-6 K-1
α (20°C; 300 °C) -0.4 – 0.9 x 10-6 K-1
α (300°C; 700 °C) 0.1 – 1.6 x 10-6 K-1
Key properties
Thermal shock resistance of up to 820°C
  • No risk of material failure when exposed to extreme thermal shocks or uneven heating
  • Rapid heating up or cooling down from high temperatures
Near-zero CTE
  • High dimensional accuracy even under fluctuating temperature conditions
Operating temperature
of up to 950°C
  • Reliable performance in temperature ranges where other technical glasses fail
Thermal shock resistance of SCHOTT NEXTREMA® glass-ceramics
Thermal expansion in dependence on the temperature
SCHOTT NEXTREMA® thermal expansion thermal characteristics

Specific heat capacity

Cp (20 – 100 °C) 0.80 – 0.85 J / (g x K)  

Thermal conductivity
(DIN 51936, ASTM E 1461-01)           

λ (90 °C) 1.5 – 1.7 W / (m x K)

Homogeneous heating of the material
TTLC / Short term load (1h) [°C] 880 – 950 / [°F] 1 616 – 1 742  
TTLC / Continuous load (5000 h) [°C] 700 – 850 / [°F] 1 292 – 1 562

Inhomogeneous heating of the material
TTLC / Short term load (1h) [°C] 450 – 750 / [°F] 842 – 1 382  
TTLC / Continuous load (5000 h) [°C] 400 – 560 / [°F] 752 – 1 040

MTG 400 – 800 K
Resistance of the material to temperature differences between a defined hot zone 
and cold edge of room temperature, without cracking due to thermal stress.
   Maximum temperature 
   gradient (MTG)
TSR 700 – 820 °C ( 1,292 - 1,508 °F)
Resistance of the material to thermal shock when the hot material is splashed with
cold water at room temperature, without cracking due to thermal stress.
   Thermal shock resistance 
The temperature / time load capacity specifies the maximum permissible temperatures
for load times of the material, below which no cracking should occur due to thermal stress.
The temperature / time load data for uneven and even temperature distributions
(e.g. homogeneous heating conditions) within the material are different.
   Temperature/time load
   capacity (TTLC)
Thermal expansion
SCHOTT NEXTREMA® transparent (724-3)
Thermal expansion
SCHOTT NEXTREMA® opaque white (724-8)
Thermal expansion
SCHOTT NEXTREMA® tinted (712-3)
Further information on request.