induction brazing steel carbide cap to shaft

Objective High Frequency Induction brazing steel carbide cap to shaft.  Customer currently uses a torch process, but would like to change to induction brazing in order to reduce scrap and rework and improve the quality of the braze.

Equipment DW-UHF-6kw-III handheld induction brazing heater Materials • Carbon steel • magnetic carbide caps • Alloy – EZ Flo 3 paste • Test 1: Shaft Diameter: 0.5” (12.7 mm) • Test 2: Shaft Diameter: 0.375” (9.525mm) • Test 3: Shaft Diameter: 0.312” (7.925mm)

Key Parameters Test 1: Shaft Diameter: 0.5” (12.7mm) Temperature: Approximately 1450°F (788°C) Power: Pre-curie – 3.3 kW Time: 11 seconds

Key Parameters Test 2: Shaft Diameter: 0.375” (9.525mm) Temperature: Approximately 1450°F (788°C) Power: Pre-curie – 1.8 kW Time: 8 seconds

Key Parameters Test 3: Shaft Diameter: 0.312” (7.925mm) Temperature: Approximately 1450°F (788°C) Power: Pre-curie – 1.7 kW Time: 7.5 seconds

Process:

1. Paste alloy was applied to the cone shape top of each steel shaft.
2. The cap was set on top and rotated to distribute the paste alloy.
3. Each assembly was positioned in the coil and heated.
4. Preliminary heat tests were conducted using tempilaq paint to estimate the heat cycle to 1450 degrees F.

Results/Benefits:

• Precise control of the time and temperature resulting in improved quality and consistent result
• Power on demand with rapid heat cycles
• Repeatable process, not operator dependent
• Safe induction heating with no open flames
• Energy efficient heating