Sialon ULTRA™ Thermocouple Protection Tubes (sheaths) are premium advanced silicon nitride-based ceramics (Si₃Al₃O₃N₅) designed for reliable, long-life temperature measurement in the non-ferrous industry. They excel in both direct and indirect sensing in molten aluminium and other non-ferrous metals – ideal for furnace walls/roofs, low-pressure die-casting machines (e.g. aluminium wheel production), launders and pouring troughs.
New option: lengths up to 1,600 mm (63 inches). Maximum operating temperature is 1,250 °C in air and up to 1,400 °C in controlled atmosphere. The unique Sialon composition delivers superior thermal shock resistance, high impact toughness, chemical inertness, zero water absorption and excellent non-wetting properties – far outperforming aluminium titanate or standard silicon nitride in aggressive molten-metal environments.
Available in four premium grades (ULTRA-001 to ULTRA-004) with outstanding mechanical and thermal properties:
Since 1986, Sialon thermocouple sheaths have been the preferred choice for foundries requiring precise temperature control, minimal maintenance and maximum reliability. They integrate perfectly with Sialon immersion heaters, riser tubes and degassing systems. View Sialon Thermocouple Protection Tubes – custom lengths, diameters and mounting options available. Standard 1-year (12-month) warranty against chemical attack in molten aluminium.
| Material data sheet | Sialon (Si3Al3O3N5) | ||||
Typical Sialon ULTRA grades |
ULTRA-001 | ULTRA-002 | ULTRA-003 | ULTRA-004 | |
| Bulk Density | g/cm3 | 3.2 | 3.1 | 3.3 | 3.2 |
| Water Absorption | ％ | 0 | 0 | 0 | 0 |
| Flexural Strength | MPa | 580 | 900 | 1,020 | 790 |
| Vickers Hardness HV1 | GPa | 13.9 | 12.7 | 15.0 | 13.8 |
| Fracture Toughness （SEPB） | MPam1/2 | 4 ～ 5 | 6 ～ 7 | 7 | 6 ～ 7 |
| Young’s Modulus of Elasticity | GPa | 290 | 270 | 300 | 290 |
| Poisson’s Ratio | – | 0.28 | 0.28 | 0.28 | 0.28 |
| Coefficient of Linear Thermal (40 – 800 °C) Expansion |
×10-6/℃ | 3.2 | 3.4 | 3.3 | 3.5 |
| Thermal Conductivity （20℃） | W/(m・k) | 25 | 23 | 27 | 54 |
| Specific Heat | J/(g・k) | 0.64 | 0.66 | 0.65 | 0.66 |
| Heat Shock Resistance | ℃ | 550 | 800 | 800 | 900 |
| Volume Resistivity （20℃） | Ω・cm | >1014 | >1014 | >1014 | >1014 |
Sialon ULTRA™ Thermocouple Protection Tubes (sheaths) are premium advanced silicon nitride-based ceramics (Si₃Al₃O₃N₅) designed for reliable, long-life temperature measurement in the non-ferrous industry. They excel in both direct and indirect sensing in molten aluminium and other non-ferrous metals – ideal for furnace walls/roofs, low-pressure die-casting machines (e.g. aluminium wheel production), launders and pouring troughs.
New option: lengths up to 1,600 mm (63 inches). Maximum operating temperature is 1,250 °C in air and up to 1,400 °C in controlled atmosphere. The unique Sialon composition delivers superior thermal shock resistance, high impact toughness, chemical inertness, zero water absorption and excellent non-wetting properties – far outperforming aluminium titanate or standard silicon nitride in aggressive molten-metal environments.
Available in four premium grades (ULTRA-001 to ULTRA-004) with outstanding mechanical and thermal properties:
Since 1986, Sialon thermocouple sheaths have been the preferred choice for foundries requiring precise temperature control, minimal maintenance and maximum reliability. They integrate perfectly with Sialon immersion heaters, riser tubes and degassing systems. View Sialon Thermocouple Protection Tubes – custom lengths, diameters and mounting options available. Standard 1-year (12-month) warranty against chemical attack in molten aluminium.
| Material data sheet | Sialon (Si3Al3O3N5) | ||||
Typical Sialon ULTRA grades |
ULTRA-001 | ULTRA-002 | ULTRA-003 | ULTRA-004 | |
| Bulk Density | g/cm3 | 3.2 | 3.1 | 3.3 | 3.2 |
| Water Absorption | ％ | 0 | 0 | 0 | 0 |
| Flexural Strength | MPa | 580 | 900 | 1,020 | 790 |
| Vickers Hardness HV1 | GPa | 13.9 | 12.7 | 15.0 | 13.8 |
| Fracture Toughness （SEPB） | MPam1/2 | 4 ～ 5 | 6 ～ 7 | 7 | 6 ～ 7 |
| Young’s Modulus of Elasticity | GPa | 290 | 270 | 300 | 290 |
| Poisson’s Ratio | – | 0.28 | 0.28 | 0.28 | 0.28 |
| Coefficient of Linear Thermal (40 – 800 °C) Expansion |
×10-6/℃ | 3.2 | 3.4 | 3.3 | 3.5 |
| Thermal Conductivity （20℃） | W/(m・k) | 25 | 23 | 27 | 54 |
| Specific Heat | J/(g・k) | 0.64 | 0.66 | 0.65 | 0.66 |
| Heat Shock Resistance | ℃ | 550 | 800 | 800 | 900 |
| Volume Resistivity （20℃） | Ω・cm | >1014 | >1014 | >1014 | >1014 |
Sialon ULTRA™ Thermocouple Protection Tubes (sheaths) are premium advanced silicon nitride-based ceramics (Si₃Al₃O₃N₅) designed for reliable, long-life temperature measurement in the non-ferrous industry. They excel in both direct and indirect sensing in molten aluminium and other non-ferrous metals – ideal for furnace walls/roofs, low-pressure die-casting machines (e.g. aluminium wheel production), launders and pouring troughs.
New option: lengths up to 1,600 mm (63 inches). Maximum operating temperature is 1,250 °C in air and up to 1,400 °C in controlled atmosphere. The unique Sialon composition delivers superior thermal shock resistance, high impact toughness, chemical inertness, zero water absorption and excellent non-wetting properties – far outperforming aluminium titanate or standard silicon nitride in aggressive molten-metal environments.
Available in four premium grades (ULTRA-001 to ULTRA-004) with outstanding mechanical and thermal properties:
Since 1986, Sialon thermocouple sheaths have been the preferred choice for foundries requiring precise temperature control, minimal maintenance and maximum reliability. They integrate perfectly with Sialon immersion heaters, riser tubes and degassing systems. View Sialon Thermocouple Protection Tubes – custom lengths, diameters and mounting options available. Standard 1-year (12-month) warranty against chemical attack in molten aluminium.
| Material data sheet | Sialon (Si3Al3O3N5) | ||||
Typical Sialon ULTRA grades |
ULTRA-001 | ULTRA-002 | ULTRA-003 | ULTRA-004 | |
| Bulk Density | g/cm3 | 3.2 | 3.1 | 3.3 | 3.2 |
| Water Absorption | ％ | 0 | 0 | 0 | 0 |
| Flexural Strength | MPa | 580 | 900 | 1,020 | 790 |
| Vickers Hardness HV1 | GPa | 13.9 | 12.7 | 15.0 | 13.8 |
| Fracture Toughness （SEPB） | MPam1/2 | 4 ～ 5 | 6 ～ 7 | 7 | 6 ～ 7 |
| Young’s Modulus of Elasticity | GPa | 290 | 270 | 300 | 290 |
| Poisson’s Ratio | – | 0.28 | 0.28 | 0.28 | 0.28 |
| Coefficient of Linear Thermal (40 – 800 °C) Expansion |
×10-6/℃ | 3.2 | 3.4 | 3.3 | 3.5 |
| Thermal Conductivity （20℃） | W/(m・k) | 25 | 23 | 27 | 54 |
| Specific Heat | J/(g・k) | 0.64 | 0.66 | 0.65 | 0.66 |
| Heat Shock Resistance | ℃ | 550 | 800 | 800 | 900 |
| Volume Resistivity （20℃） | Ω・cm | >1014 | >1014 | >1014 | >1014 |
Sialon ULTRA™ Thermocouple Protection Tubes (sheaths) are premium advanced silicon nitride-based ceramics (Si₃Al₃O₃N₅) designed for reliable, long-life temperature measurement in the non-ferrous industry. They excel in both direct and indirect sensing in molten aluminium and other non-ferrous metals – ideal for furnace walls/roofs, low-pressure die-casting machines (e.g. aluminium wheel production), launders and pouring troughs.
New option: lengths up to 1,600 mm (63 inches). Maximum operating temperature is 1,250 °C in air and up to 1,400 °C in controlled atmosphere. The unique Sialon composition delivers superior thermal shock resistance, high impact toughness, chemical inertness, zero water absorption and excellent non-wetting properties – far outperforming aluminium titanate or standard silicon nitride in aggressive molten-metal environments.
Available in four premium grades (ULTRA-001 to ULTRA-004) with outstanding mechanical and thermal properties:
Since 1986, Sialon thermocouple sheaths have been the preferred choice for foundries requiring precise temperature control, minimal maintenance and maximum reliability. They integrate perfectly with Sialon immersion heaters, riser tubes and degassing systems. View Sialon Thermocouple Protection Tubes – custom lengths, diameters and mounting options available. Standard 1-year (12-month) warranty against chemical attack in molten aluminium.
| Material data sheet | Sialon (Si3Al3O3N5) | ||||
Typical Sialon ULTRA grades |
ULTRA-001 | ULTRA-002 | ULTRA-003 | ULTRA-004 | |
| Bulk Density | g/cm3 | 3.2 | 3.1 | 3.3 | 3.2 |
| Water Absorption | ％ | 0 | 0 | 0 | 0 |
| Flexural Strength | MPa | 580 | 900 | 1,020 | 790 |
| Vickers Hardness HV1 | GPa | 13.9 | 12.7 | 15.0 | 13.8 |
| Fracture Toughness （SEPB） | MPam1/2 | 4 ～ 5 | 6 ～ 7 | 7 | 6 ～ 7 |
| Young’s Modulus of Elasticity | GPa | 290 | 270 | 300 | 290 |
| Poisson’s Ratio | – | 0.28 | 0.28 | 0.28 | 0.28 |
| Coefficient of Linear Thermal (40 – 800 °C) Expansion |
×10-6/℃ | 3.2 | 3.4 | 3.3 | 3.5 |
| Thermal Conductivity （20℃） | W/(m・k) | 25 | 23 | 27 | 54 |
| Specific Heat | J/(g・k) | 0.64 | 0.66 | 0.65 | 0.66 |
| Heat Shock Resistance | ℃ | 550 | 800 | 800 | 900 |
| Volume Resistivity （20℃） | Ω・cm | >1014 | >1014 | >1014 | >1014 |
We ship usually within 4 weeks
In molten aluminium baths
Since 1986
Sweden / Sverige
+(46) 31 754 0790
Denmark
+(45) 35 15 8085
USA/Canada Tollfree
+ 1 (833) 709-1399
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