Hard drawn copper refers to copper wire that has been cold-drawn through a series of dies without subsequent annealing (heat treatment). This process increases the tensile strength and hardness of the copper while reducing its ductility (flexibility).
🔹 How It’s Made
The production process involves:
Drawing: Pure copper rod is pulled through progressively smaller dies.
Cold Working: Each pass hardens the copper by aligning its crystal structure.
No Annealing: Unlike soft (annealed) copper, hard drawn copper is not heated afterward, keeping it strong and stiff.
🔹 Key Characteristics
| Property | Hard Drawn Copper | Annealed (Soft) Copper |
|---|---|---|
| Tensile Strength | Higher (≈ 350–400 MPa) | Lower (≈ 200–250 MPa) |
| Flexibility | Low (less bendable) | High (very flexible) |
| Conductivity | Slightly lower (≈ 97–98% IACS) | Higher (≈ 100% IACS) |
| Durability | Excellent for tension and mechanical stress | Better for frequent bending or vibration |
🔹 Applications
Hard drawn copper is widely used in applications requiring mechanical strength and dimensional stability, including:
Overhead power transmission lines
Trolley wires and railway electrification
Grounding conductors
Busbars and electrical panels
Antenna and telecommunication systems
Because of its rigidity, it’s often installed where minimal movement or bending occurs after installation.
🔹 Advantages
Excellent mechanical strength
Good electrical conductivity
High resistance to stretching and deformation
Long service life under tension
🔹 In Summary
Hard drawn copper combines strength, stability, and good conductivity, making it a preferred material for power transmission and structural electrical applications. While not as flexible as annealed copper, its ability to withstand tension and harsh environments makes it an essential material in modern electrical infrastructure.
👉 Looking for high-quality hard drawn copper wire or conductors?
TOT Wire & Cable supplies reliable, high-tensile copper conductors for power, telecom, and industrial applications — ensuring both strength and performance.
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