Micro-Welding Nickel to Copper for High-Efficiency Heater Elements 

The Challenge

An industrial heating equipment manufacturer needed to fabricate a high-efficiency heater element by joining 0.025" nickel wires to copper terminals for an air circulation heater. Nickel’s resistance to high temperatures and copper’s superior conductivity made them a perfect pair for delivering consistent heat output, but welding them was tricky. Traditional resistance welding struggled with inconsistent bonds due to differing melting points (nickel ~1455°C, copper ~1085°C), risking weak joints under thermal cycling. Brazing added filler materials, reducing conductivity and complicating assembly. The goal: a clean, strong weld—no filler—that ensured durability and efficiency in a compact heater design.

The Percussion Welder Solution

The Model 858 Percussion Welder, equipped with the 726 Bench Fixture and 808 Actuator, rose to the challenge. The team dialed in table parameters for nickel-to-copper at 0.025": 78V actuator velocity, 1.00ms timing delay, and a long 50V pulse (Bank 3, 8,430 µF capacitance). The process unfolded seamlessly:

• Preparation: The 726 Fixture’s Z-axis and Y-axis adjustments aligned the 0.025" nickel wire and copper terminal with a pre-defined gap, secured by the moveable wireholder and stationary holder for optimal arc initiation.
• Rapid Heating: The 858’s front panel unleashed a 78V micro-arc, heating the surfaces in 1–4 milliseconds—fast enough to limit heat spread and prevent copper softening, controlled via the 1.00ms delay (0.5–5ms range).
• Percussion Phase: The 808 Actuator, at 78V (up to 33 in/s speed), thrust the molten materials together with <100g force, forming a robust bond in under 3ms—no filler, no distortion.
• Outcome: A clean, repeatable weld with excellent electrical conductivity and thermal stability, perfect for heater elements. The 78V velocity drove the actuator’s rapid thrust (0–30 Joules), while the 50V long pulse ensured deep fusion without overcooking the copper—balancing strength and material integrity.

The 858’s adjustable controls—pulse width, polarity, and capacitance—allowed scalability, with table data showing success at 0.020" (70V, 55V pulse) and 0.032" (62V, 45V pulse), proving versatility for heater coil production.

The Result

The welds delivered industrial-grade performance:

• Strength: Estimated 450 psi tensile strength—exceeding typical heater element stress requirements—thanks to the 808’s precise thrust and 50V pulse depth.
• Speed: <3ms per weld, 25–40% faster than resistance welding (4ms) or brazing (7ms), enabling a batch of 1,000 welds in 3 seconds vs. 7 seconds for brazing.
• Efficiency: HAZ at ~0.1mm preserved copper’s conductivity and nickel’s heat resistance, ensuring consistent 500W output at 120V—crucial for air heater longevity.

Visualizing the Impact

These charts compare the 858 Percussion Welder to resistance welding and brazing on speed and conductivity retention—key for heater element engineers.

Chart 1: Production Speed Comparison

Time for 1,000 welds: Percussion (3s), Resistance (4s), Brazing (7s). A 25–57% edge boosts throughput.

Chart 2: Conductivity Retention Comparison

Post-weld conductivity (relative to pure copper): Percussion (95%), Resistance (85%), Brazing (80%). Higher retention enhances efficiency.

Engineer’s Takeaway

“The 858 Percussion Welder transforms heater element production,” said a lead engineer. “Its speed and precision fuse nickel to copper flawlessly, delivering durable, efficient coils that traditional methods can’t match.”

Ready to Heat Up Your Production?

Elevate your heater elements with the Model 858. Contact us at 303-536-7838 or explore thePercussion Welder specs.