T1-Thermocouple Alloy，1

### **T1 Thermocouple Alloy (Copper / Constantan) - Type T Thermocouple Positive Leg** #### **Overview** **T1 Thermocouple Alloy** represents the positive leg material of Type T thermocouples, consisting of high-purity **copper (Cu+)**. When paired with Constantan (Cu-Ni alloy, negative leg), it forms one of the most widely used thermocouple combinations for low-temperature measurements. Type T thermocouples are renowned for their excellent stability, accuracy, and reproducibility in cryogenic to moderate temperature ranges, making them indispensable in scientific research, industrial processes, and HVAC applications. --- #### **Chemical Composition (Weight %)** | Element | Content (%) | Notes | |---------|-------------|-------| | **Copper (Cu)** | **≥ 99.95%** | High-purity electrolytic copper | | **Oxygen (O)** | **≤ 0.02%** | Oxygen-free grade typically used | | **Other Impurities** | **≤ 0.03%** | Total other elements (Fe, Pb, S, etc.) | *Note: The exceptional purity is critical for consistent thermoelectric properties and oxidation resistance.* --- #### **Physical & Mechanical Properties** | Property | Value / Description | |----------|---------------------| | **Density** | **8.94 g/cm³** | | **Melting Point** | **1084.6°C** (1984.3°F) | | **Electrical Resistivity** | **1.68 μΩ·cm** (at 20°C) | | **Thermal Conductivity** | **401 W/m·K** (at 20°C) | | **Coefficient of Thermal Expansion** | **16.5 × 10⁻⁶/°C** (20-100°C) | | **Specific Heat Capacity** | **385 J/kg·K** | | **Tensile Strength** | **210-340 MPa** (annealed) | | **Yield Strength** | **33-70 MPa** (annealed) | | **Elongation** | **45-60%** | | **Hardness** | **35-65 HV** | --- #### **Thermoelectric Properties (with Constantan)** | Parameter | Value / Range | |-----------|---------------| | **Temperature Range** | **-200°C to +370°C** (-328°F to +700°F) | | **Standard Limits** | **-200°C to +400°C** | | **Seebeck Coefficient** | **~40-60 μV/°C** (temperature dependent) | | **EMF Output** | **~4.3 mV at 100°C** (reference junction at 0°C) | | **Accuracy** | **±0.5°C or ±0.4%** (whichever is greater) | | **Stability** | **Excellent in inert/reducing atmospheres** | --- #### **Key Characteristics & Applications** **Key Characteristics:** - **Excellent Low-Temperature Performance**: Superior accuracy in cryogenic applications - **High Thermal Conductivity**: Fast response time - **Excellent Ductility**: Easy to form and install - **Oxidation Sensitivity**: Limited use in oxidizing atmospheres above 370°C - **Moisture Resistance**: Good performance in humid environments - **Non-Magnetic**: Suitable for magnetic-sensitive applications **Typical Applications:** - **Cryogenics**: Liquid nitrogen and helium temperature measurements - **HVAC Systems**: Air conditioning and refrigeration monitoring - **Food Processing**: Freezing, cooling, and storage applications - **Pharmaceutical**: Laboratory and production temperature control - **Scientific Research**: Precision temperature measurement - **Plastic Processing**: Extrusion and molding temperature monitoring - **Energy Systems**: Heat pump and geothermal applications --- #### **International Standards & Specifications** | Standard | Designation | Description | |----------|-------------|-------------| | **ASTM** | **E230** | Temperature-Electromotive Force (EMF) Tables | | **IEC** | **60584-1** | Thermocouples - Part 1: EMF specifications | | **ANSI** | **MC96.1** | Temperature Measurement Thermocouples | | **BS** | **EN 60584-1** | British European Standard | | **JIS** | **C1602** | Japanese Industrial Standard | | **DIN** | **43710** | German Standard | --- #### **Wire Specifications & Configurations** | Wire Size | Temperature Range | Typical Application | |-----------|-------------------|---------------------| | **AWG 8-14** | **Up to 370°C** | Industrial processes | | **AWG 20-24** | **Up to 200°C** | General purpose | | **AWG 28-40** | **Up to 150°C** | Laboratory precision | | **MIMS Cable** | **Various** | Harsh environments | --- #### **Environmental Considerations** | Environment | Suitability | Notes | |-------------|-------------|-------| | **Oxidizing** | **Poor above 370°C** | Copper oxidizes rapidly | | **Reducing** | **Good** | Suitable for hydrogen atmospheres | | **Vacuum** | **Excellent** | No oxidation issues | | **Moist** | **Good** | Resists corrosion | | **Sulfur-containing** | **Poor** | Forms corrosive copper sulfide | --- #### **Quality Control & Testing** - **EMF Calibration**: Verification against standard reference tables - **Homogeneity Testing**: Ensuring consistent thermoelectric properties - **Insulation Resistance**: Critical for insulated wire versions - **Diameter Tolerance**: Typically ±0.5% for precision applications - **Surface Quality**: Must be free from oxides and contaminants --- #### **Comparison with Other Thermocouple Types** | Type | Materials | Range | Advantages | |------|-----------|-------|------------| | **T** | **Cu vs Constantan** | **-200 to 370°C** | Best low-temperature accuracy | | **J** | Iron vs Constantan | 0 to 760°C | Higher temperature capability | | **K** | Ni-Cr vs Ni-Al | -200 to 1260°C | Wide range, general purpose | | **E** | Ni-Cr vs Constantan | -200 to 900°C | Highest EMF output | --- #### **Summary** **T1 Thermocouple Alloy (High-Purity Copper)** serves as the critical positive element in Type T thermocouples, offering unparalleled performance in low-temperature and cryogenic applications. Its exceptional purity ensures consistent thermoelectric properties, while its high thermal conductivity provides rapid response times. Although limited by oxidation sensitivity at elevated temperatures, its excellent accuracy, stability, and reproducibility in the -200°C to +370°C range make it the preferred choice for precision temperature measurement in scientific, industrial, and commercial applications. Comprehensive international standardization and well-established manufacturing practices ensure reliable performance across diverse measurement scenarios, particularly where low-temperature accuracy is paramount.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3236 gallon liquid totes Special package is available on request.