Case Carburizing process.

Case hardening Process

Case hardening is a material processing method that is used to increase the hardness of the outer surface of a metal. Case hardening results in a very thin layer of metal that is notably harder than the larger volume of metal underneath of the hardened layer.

- It is mainly used on low-carbon steels. The part is heated to 871–954 °C (1600–1750 °F)

- Attempt to harden an entire metal object. One reason is efficiency. Less energy and less time are required to heat the outermost surface of a metal as opposed to its entire cross section.

- A hard outside shell and a more ductile interior.

What Types of Metals Can Be Case Hardened?

Metals that can be case hardened are generally limited to ferrous materials, although there are special cases such as the Nitriding of some titanium or aluminum alloys. The ferrous metals commonly case hardened are.

Gears

Fasteners

Camshafts

Rods

Pins

--BENEFITS OF CASE HARDENING

Creating a more durable product

Increases wear-resistance of the metal

Increases lifetime of objects

Case hardening or surface hardening makes steel easier to weld

The metal is more flexible

Steel is tougher and stronger.

Time and temperature determines how deep into the surface the hardening extends.

The depth of hardening is ultimately limited by the inability of carbon to diffuse deeply into solid steel, and a typical depth of surface hardening with this method is up to 1.5 mm.

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