Case hardening

Case hardening is a thermochemical hardening process used in the metalworking industry to improve the surface hardness of workpieces. Unlike the continuous hardening method, only the outer layer of the workpiece is treated during case hardening, resulting in a hardened surface with a tough core.

During the case hardening process, the workpiece is heated to a certain temperature to make it receptive to the diffusion of carbon or nitrogen. The workpiece is then placed in an atmosphere containing carbon or nitrogen, allowing these elements to penetrate the outer layer of the metal. This leads to the formation of carbide compounds that improve the hardness of the surface.

The key advantage of case hardening is the ability to concentrate the hardness on specific areas of the workpiece surface, while the core of the workpiece retains its original toughness. This makes it possible to precisely adjust the mechanical properties of the workpiece according to the requirements of the application.

Case hardening is often used in the manufacture of tools, gears, bearings and other components subject to wear where a combination of high hardness on the surface and toughness in the core is required. The targeted application of this hardening process can make workpieces more durable and resistant to wear and fatigue.