What Is Induction Hardening?

Induction is used to elevate the surface temperature of steel or other alloy in order to improve the wear resistance or to treat a select region of the material.

How Induction Hardening Works

Induction hardening and heat treating are ideal for many applications in the transportation, aerospace, and energy industries, for processes like through hardening and case hardening.

Induction Hardening Offers Numerous Benefits

  • Dramatic energy savings due to process efficiency

  • Minimal distortion

  • Higher throughput and productivity

  • Superior precision and unrivaled repeatability

  • Easy automation and incorporation into existing production lines

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Induction hardening Application Notes

Click to read how induction hardening can improve the efficiency, effectiveness and safety of your heating process.

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Hardening surgical blades Hardening surgical blades

To quickly heat a steel surgical blade to 2000°F (1093°C) within 2 seconds so as to harden the blade edge.

Hardening Seat Belt PartsHardening Seat Belt Parts

A four-turn helical concentrating coil is specially designed to deliver uniform heat to the steel seat belt retraction gear.

Hardening the teeth of a large saw bladeHardening the teeth of a large saw blade

A torch isn't as precise as induction nor is it repeatable; induction heating is highly repeatable, uses less energy than a torch and offers instant on/off heating

Case hardening a steel fitting (machined parts manufacturer)Case hardening a steel fitting (machined parts manufacturer)

The coil design enabled the part to be raised into the heating coilfrom the bottom. The design was also made to ensure it will work well within the customer's current setup...

Surface hardening of steel screwsSurface hardening of steel screws

Induction heating enables precise application of heat, faster process time and production rates and the ability to be incorporated into existing production lines

Hardening teeth on a steel motorcycle gearHardening teeth on a steel motorcycle gear

A single turn helical coil is used to heat the gear. The gear is placed on a spindle and rotated at 300-350 RPM's.

Hardening steel screw threadsHardening steel screw threads

A five turn helical coil is used heat the screw threads. The screw is placed in the coil, heat is applied for 8 seconds to achieve a 2 long zone at the required hardness.

Hardening the end of steel hand-held marking stampsHardening the end of steel hand-held marking stamps

To harden various size ends of hand held marking stamps. The area to be hardened is 3/4 (19mm) up the shank.

Hardening of Steel Cam AssemblyHardening of Steel Cam Assembly

Hardening the cam outer surfaces with induction results in uniform heating for uniform results, one coil can be used for many geometries, consistent results from piece to piece

Case Hardening of Armature ShaftCase Hardening of Armature Shaft

A five turn helical coil is used to heat the gear end of the shaft to 1700°F

Hardening Cast Iron PulleysHardening Cast Iron Pulleys

Heat cast iron pulleys to 1600°F(871.1°C) in order to achieve a hardness of 55 Rockwell C.

Hardening Stainless Steel Surgical Knife BladesHardening Stainless Steel Surgical Knife Blades

A two turn helical coil with an internal quartz tube designed to scan the length of the blade is used to heat the blade to 1850°F (1010°C) to achieve the desired hardness.

Hardening Bed Knife Blade for Reel Type Lawn MowersHardening Bed Knife Blade for Reel Type Lawn Mowers

The hardness desired is between 45 to 55 Rockwell C, and should be measured 0.062in (1.6mm) from the cutting edge.

Materials that can be hardened with induction

Induction can be applied to harden many types of cast irons and steel alloys. 

Heat Treating Applications

Through hardening treats the entire part and is used on medium and high carbon steels for moderate strength and surface hardness. Because through hardening requires a deep penetrating heat that can damage the surface of a component if not regulated precisely, induction heating is an excellent solution for this application.

Case hardening treats the part’s surface area and some of the interior area, according to the depth of hardening requirements of the application.

Popular hardening Note

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Induction hardening Resources:

Select from our libraries of materials to help you better understand the benefits hardening with induction heating can bring to your process.

About Induction Heating

Induction heating is a fast, efficient, precise and repeatable non-contact method for heating metals or other electrically-conductive materials. The material may be a metal such as brass, aluminum, copper or steel or it can be a semiconductor such as silicon carbide, carbon or graphite. To heat non-conductive materials such as plastics or glass, induction is used to heat an electrically-conductive susceptor, typically graphite, which then transfers the heat to the non-conducting material.

Read our 4-page brochure; learn more about how the science of induction technology can solve your precision heating problems.

Read 'About Induction Heating'

Brochure: About Induction Heating

Induction Heating Work Coils

The work coil is the component in the induction heating system that defines how effective and how efficiently your work piece is heated.

Read our informative brochure explaining the fundamentals of induction coils and their design.

Read 'Induction Heating Work Coils'

Induction Heating Work Coils

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