NEXTREMA®
SCHOTT NEXTREMA® optical properties
NEXTREMA® offers six transmission profiles in the visible and infrared range depending on material type and material thickness. For engineers and designers, that means NEXTREMA® is the material of choice when it comes to light transmission and infrared radiation, for example in radiant heaters. The six different NEXTREMA® variants offer a transmission portfolio dependant on your needs, making this a reliable material partner for industry and home.
| Key properties | Benefits | tinted (712-3) |
translucent bluegrey (712-6) |
opaque grey (712-8) |
transparent (724-3) |
translucent white (724-5) |
opaque white (724-8) |
|---|---|---|---|---|---|---|---|
| 6 transmission profiles in visible range (400 - 800 nm) | 6 design options | black | blue | grey | transparent | white | white |
| Glare reduction | yes | yes | yes | yes | yes | ||
| Light diffusion | yes | yes | |||||
| Light blocking | yes | yes | |||||
| 6 transmission profilesin infrared range (800 - 4500 nm) | Efficient IR heater cover | yes | yes | yes | yes | ||
| Selective IR transmission | yes | yes | |||||
| Compatible with different IR heaters | yes | yes | yes | yes | yes | yes |
Transmission
Transmission values are measured for a polished sample of a specific thickness.
This graph is based on data from individual measurements. Deviations may result from the manufacturing process. Typical transmission graph of different ceramization states with sample thickness of approximately 4 mm.
SCHOTT NEXTREMA® mechanical properties
NEXTREMA® boasts a very high degree of mechanical strength for a ceramic material and doesn’t require any additional toughening processes. The glass-ceramic also exhibits extraordinary mechanical stability, even at high temperatures. The NEXTREMA® variant with the highest bending strength is tinted (712-3), which can withstand a force of up to 165 megapascals.
| Key properties | Benefits | tinted (712-3) | translucent bluegrey (712-6) |
opaque grey (712-8) |
transparent (724-3) |
translucent white (724-5) |
opaque white (724-8) |
|---|---|---|---|---|---|---|---|
| Bending strenght of up to 165 MPa (thickness 4mm) | High material streght without tempering | yes | yes | yes | yes | yes | yes |
| Reliable material strenght under high temperatures | yes | yes | yes | yes | yes | yes | |
| Surface/ Knoop harness of up to 620 | Good abrasion resistance | yes | yes | yes | yes | yes | yes |
| Density of ~2,5 g/cm3 | Lightweight compared to technical ceramics | yes | yes | yes | yes | yes | yes |
- Density: ρ approx. 2.5 – 2.6 g/cm3
- Modulus of elasticity (ASTM C-1259): E approx. 84 – 95 x 10³ MPa
- Poisson‘s ratio (ASTM C-1259): μ approx. 0.25 – 0.26
- Knoop hardness (ISO 9385): HK0.1 / 20approx. 570 – 600
- Bending strength (DIN EN 1288, Part 5, R45): σbBapprox. 100 – 165 MPa
- Porosity (ISO 9385): 0 %
- Roughness: Material 724-3 (t = 4 mm)Ra≤ 0.20 μm Rms ≤ 0.25 μ
Impact resistance
The impact resistance of NEXTREMA® depends on the size, thickness and geometry of the panel, kind of installation and type of impact, especially on drilled holes and their position in the material. Therefore, information regarding impact resistance can only be given with knowledge of the respective and defined application, especially in combination with the technical standards regarding impact resistance that have to be met for some applications. The quality of the grinding profile also has an important influence on impact resistance.
SCHOTT NEXTREMA® thermal properties
NEXTREMA® exceeds all expectations when it comes to temperature resistance. The material can withstand both extremely high and low temperatures, offering outstanding resistance up to 950 °C. From white hot to ice cold and back again, quick changes in temperature will have little impact on this heat resistant glass-ceramic, minimizing thermal stress fractures. Thanks to its near-zero thermal expansion, NEXTREMA® can also cope with temperature shocks of up to 820 °C, making it ideal for high-temperature applications.
| Key properties | Benefits | tinted (712-3) | translucent bluegrey (712-6) | opaque grey (712-8) | transparent (724-3) | translucent white (724-5) | opaque white (724-8) |
|---|---|---|---|---|---|---|---|
| Thermal shock resistance of up to 820°C | Reliable performance when exposed to thermal shocks | yes | yes | yes | yes | yes | yes |
| Rapid cooling down from extreme temperatures without cracking | yes | yes | yes | yes | yes | yes | |
| Near-zero CTE Operating temperature of up to 950°C |
Dimensional accuracy under fluctuating temperature conditions | yes | yes | yes | yes | yes | yes |
| Higher temperature resistance than most glasses (except fused silica) | yes | yes | yes | yes | yes | yes |
Thermal expansion depending on the temperature
Maximum Temperature Gradient (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.
Thermal shock resistance (TSR) 600-820°C (1,112-1,508°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.
Temperature/time load capacity
The TTLC 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.
| CTE in different temperature ranges | |
|---|---|
| α(-50 °C; 100 °C) | -0.8 – 0.6 x 10-6K-1 |
| α(0 °C; 50 °C) | -0.8 – 0.6 x 10-6K-1 |
| α(20°C; 300 °C) | -0.4 – 0.9 x 10-6K-1 |
| α(300°C; 700 °C) | 0.1 – 1.6 x 10-6K-1 |
Specific heat capacity and thermal conductivity (DIN 51936, ASTM E 1461-01)
| 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 and inhomogeneous heating of the material
| Homogeneous heating of the material | |
|---|---|
| TTLC / Short term load (1h) | >650 – 950 °C / 1,202 – 1,742 °F |
| TTLC / Continuous load (5000 h) | >550 – 850 °C / 1,022 – 1,562 °F |
| Inhomogeneous heating of the material | |
|---|---|
| TTLC / Short term load (1h) | 450 – 750 °C / 842 – 1,382 °F |
| TTLC / Continuous load (5000 h) | 400 – 560 °C / 752 – 1,040 °F |
SCHOTT NEXTREMA® chemical properties
NEXTREMA® is chemically resistant and remains stable in aggressive environments. It meets all subsequent ISO and DIN standards in its chemical resistance to acids, bases and hydrolytic influences. With the elimination of degradation enabling reliable material behavior, as well as stable process environments under typical corrosive conditions. This chemical- and base-resistant glass-ceramic is used in all fields of industrial and product design.
| Key properties | Benefits | tinted (712-3) |
translucent bluegrey (712-6) |
opaque grey (712-8) |
transparent (724-3) |
translucent white (724-5) |
opaque white (724-8) |
|---|---|---|---|---|---|---|---|
| High chemical resistance comparable to laboratory glassware | Comparable resistance to laboratory glassware | yes | yes | yes | yes | ||
| Reliable protection against corrosive environments | yes | yes | yes | yes | |||
| Non-porous, smooth surface | No outgassing in vacuum environments | yes | yes | yes | yes | yes | yes |
| No generation of particles without external influence | yes | yes | yes | yes | yes | yes |
Principal constituents (DIN EN 1748-2-1)
| Component | Symbol | Percentage per mass |
|---|---|---|
| Silicon dioxide |
SiO2 |
50 % – 80 % |
| Aluminium oxide | Al2O3 |
15 % – 27 % |
| Lithium oxide |
Li2O |
0 % – 5 % |
| Zinc oxide |
ZnO |
0 % – 5 % |
| Titanium oxide |
TiO2 |
0 % – 5 % |
| Zirconium oxide |
ZrO2 |
0 % – 5 % |
| Magnesium oxide |
MgO |
0 % – 8 % |
| Calcium oxide |
CaO |
0 % – 8 % |
| Barium oxide |
BaO |
0 % – 8 % |
| Sodium oxide |
Na2O |
0 % – 2 % |
| Potassium oxide |
K2O |
0 % – 2 % |
| Other (trace content on request) | 0 % – 5 % |
The materials do not contain any harmful substances according to the European directive 2011/65/EU “Hazardous Substances in electrical and electronically Equipment” and fulfil the terms of RoHS(II) without any concerns. NEXTREMA® glass-ceramics consist of 100% UVCB substance glass. According to REACH, this kind of glass is not classified as a hazardous substance. When used within the limitation of the according material specification, NEXTREMA® glass-ceramics do not release any hazardous substances throughout the entire life cycle (including the disposal), that would violate existing legal limits.
End of life usage
Federal Republic of Germany waste disposal regulations differentiate five classes of waste: Z0 (non-restricted disposal), Z3 (household waste), and up to Z5 (highly toxic waste). All NEXTREMA® materials are classified as non-restricted disposal. Local government regulations may differ. Please contact the local authority if needed. NEXTREMA® must not be disposed of in recycling boxes for standard glass (e g. glass bottles).
Chemical resistance
The chemical resistance of NEXTREMA® is more extensive than that of most other comparable materials.
| Tinted (712-3) | Translucent bluegrey (712-6) | Opaque grey (712-8) | Transparent (724-3) | Translucent white (724-5) | Opaque white (724-8) | |
|---|---|---|---|---|---|---|
| Hydrolytic Resistance HGB (ISO 719) | 1 | 1 | 1 | 1 | 1 | 1 |
| Acid Resistance S (DIN 12116) |
2 | 2 | 2 | 2 | 1 | 1 |
| Alkali Resistance A (ISO 695) |
1 | 2 | 2 | 1 | 1 | 1 |
1 = high resistance / low solubility
2 = medium resistance / medium solubility
3 = low resistance / high solubility
Roberto Perez Castro
Head of NEXTREMA® Product Management