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CuNi45 Constantan Round Wire, 1.20mm Diameter High-Current Copper Nickel Alloy Wire for Current Shunts & Power Resistor Manufacturing
Product Details
| Alloy Designation | CuNi45 Constantan (55Cu / 45Ni, Upgraded From Standard CuNi44 Grade) | Standard Diameter | 1.20mm |
|---|---|---|---|
| Custom Diameter Range | 0.60mm ~ 3.5mm Medium & Thick Heavy Gauges | Surface Treatment | Medium-Tension Homogenizing Annealed, Matte Bright Polished, Full Edge Deburred |
| Operating Temperature | -50°C ~ 420°C (Dry High-Current Industrial Power Equipment Atmosphere) | Reference Resistivity | 0.49 µΩ·m At 20°C Ambient Temperature |
| Temperature Coefficient Of Resistance | Low Resistance Drift Under Sustained Large Current Thermal Cycling | Processing Performance | High Tensile Breaking Strength, Withstand Heavy Winding Tension, Bendable For Large-radius Power Coil Forming |
Product Description
Product Overview
This heavy-gauge CuNi45 constantan solid wire is independently developed by Huona with standardized 55Cu–45Ni alloy ratio, specially engineered for high-current power resistive components and heavy-load shunt parts rather than miniature microcircuit use. It adopts multi-pass heavy-diameter precision drawing and medium-tension homogenizing annealing technology, delivering stable high-volume resistivity, low temperature resistance shift under large current loads, smooth scratch-free metallic surface and excellent tensile strength to withstand heavy coiling tension. Tightly layered and wound on large spoke-style black industrial plastic spools as displayed in the picture, the robust spool structure supports ultra-long continuous wire length for automated heavy resistor winding production lines. It acts as the preferred raw material for industrial current shunts, high-power load resistors and heavy-duty Type J/T thermocouple negative conductors for large mechanical thermal monitoring systems.
Core Specifications
Product Name: CuNi45 High Current Constantan Solid Round Wire
Alloy Grade: CuNi45 Constantan Alloy (55% Copper + 45% Nickel, differentiated from standard CuNi44 grade)
Processing Technology: Heavy-spec multi-stage precision wire drawing + homogenizing medium-tension annealing + full surface deburring polishing
Standard Specification: 1.20mm Nominal Diameter
Customizable Size Range: Diameter 0.60mm – 3.5mm medium to thick heavy gauges
Surface Condition: Bright matte-silver metallic finish, perfect concentric circular cross-section, free of burrs, longitudinal scratches and oxidation discoloration
Electrical Performance: High stable nominal resistivity, minimal resistance drift under sustained large current heating cycles
Operating Temperature Range: -50°C ~ 420°C (continuous stable operation under dry industrial high-current working environments)
Standards Compliance: IEC 60584, GB/T 6149, RoHS 2.0, REACH eco-friendly low-hazard material standards
Key Differentiating Advantages
1. Optimized 55Cu-45Ni Alloy Formula for High-Current Load Stability
Distinct from conventional CuNi44 grade, this CuNi45 alloy elevates nickel content to enhance structural stability under prolonged high-current heating. Strict smelting impurity control ensures consistent metallographic grain distribution, achieving ultra-low temperature coefficient of resistance even when internal wire temperature rises sharply from power load. Batch-to-batch alloy uniformity eliminates resistance deviation during mass production of industrial shunt and high-power resistance coils.
2. Outstanding Overload Thermal Stability for Power Resistor Scenarios
The upgraded copper-nickel proportion greatly improves the alloy’s anti-thermal-fatigue performance under repeated heavy current surges. It resists rapid resistance drift and local hot spot formation during long-duration power dissipation, preventing premature aging of high-load resistive components and extending the service life of industrial power control equipment far beyond thin fine-gauge constantan wire.
3. Balanced Tensile Strength & Ductility for Heavy Automated Winding
Medium-tension homogenizing annealing strikes an ideal balance between tensile breaking strength and bending flexibility. The thick-gauge wire tolerates heavy tension from industrial automatic winding machines, supporting large-radius tight coiling without fracture or permanent diameter deformation. Uniform round cross-section ensures even heat dissipation and consistent resistance distribution across high-power resistor coils under continuous current load.
4. Large Spoke-Style Spool Design for Mass Power Component Production
This CuNi45 wire is wound onto heavy-duty spoke-flange black plastic spools with extra-large single-reel wire capacity, drastically reducing production line downtime caused by reel replacement during mass manufacturing of power resistors and current shunts. Marked flange surface enables fast specification batch identification for factory inventory management, while smooth polished wire surface avoids surface abrasion under high-tension continuous unwinding.
5. Dual Function: Power Resistance & Heavy-Duty Thermocouple Leg Material
Beyond core application in high-current shunts and power resistors, CuNi45 can also serve as the negative thermocouple conductor for large industrial furnace Type J and Type T temperature probes. Its thick wire cross-section offers superior mechanical durability for rough workshop installation environments, outperforming ultra-fine constantan wires prone to breakage during field assembly of heavy machinery thermal sensors.
Technical Specifications Table
| Attribute | Typical Specification |
|---|---|
| Alloy Designation | CuNi45 Constantan (55Cu / 45Ni, upgraded from standard CuNi44 grade) |
| Standard Diameter | 1.20mm |
| Custom Diameter Range | 0.60mm ~ 3.5mm Medium & Thick Heavy Gauges |
| Surface Treatment | Medium-Tension Homogenizing Annealed, Matte Bright Polished, Full Edge Deburred |
| Operating Temperature | -50°C ~ 420°C (Dry High-Current Industrial Power Equipment Atmosphere) |
| Reference Resistivity | 0.49 µΩ·m at 20°C ambient temperature |
| Temperature Coefficient of Resistance | Low resistance drift under sustained large current thermal cycling |
| Processing Performance | High tensile breaking strength, withstand heavy winding tension, bendable for large-radius power coil forming |
Supply & Packaging Standard
Supply Form: Continuous thick-gauge solid CuNi45 wire densely and orderly wound on large spoke-flange heavy-duty black industrial plastic spools; standard full-length large reels and custom cut fixed-length thick wire coils both available
Packaging: Each large spool wrapped with thick dust-proof moisture-proof outer bag plus hard foam shockproof padding, optimized for bulk heavy industrial factory procurement and long-distance export logistics
MOQ: 1 large spoke-style black spool for power resistor prototype trial coiling; large-volume bulk supply for industrial shunt manufacturers, high-power resistance component factories and heavy machinery thermosensor producers
Customization Service: Custom thick wire diameter, single spool total winding length, annealing tensile strength grade and surface finish based on high-current shunt and power resistance coil mass production demands
Typical Application Scope
Industrial Current Shunt Component Production: Primary raw material for high-precision heavy-load current shunts used in power distribution cabinets, battery testing equipment and welding control devices.
High-Power Load Resistor Manufacturing: Core winding wire for industrial power load resistors, braking resistors and discharge resistance coils for automation power control systems.
Heavy-Duty Industrial Thermocouple Negative Legs: Durable matching negative alloy wire for thick Type J & Type T temperature sensing cables and furnace wall-mounted heavy contact thermocouple probes.
Large Machinery Thermal Monitoring Assemblies: Robust temperature detection wire for metal forging furnaces, extrusion machinery and heavy-duty industrial oven long-term thermal tracking.
Power Calibration & Testing Equipment Parts: Stable high-current resistive wire for laboratory power calibration benches, battery aging test fixtures and industrial electrical measuring instruments.
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