What material properties does case hardening primarily aim to enhance?

Case hardening is a heat treatment process that primarily aims to augment the surface hardness of a material, typically steel, while preserving the toughness and ductility of its core. This process involves altering the surface layer of the material, essentially by introducing carbon or nitrogen into the outer layer, which results in enhanced hardness right at the surface where wear and abrasion are most likely to occur. By achieving this increased hardness on the surface, the material can better resist wear without compromising its overall structural integrity, which is critical for components that experience high stress or impact loads.

The maintenance of core toughness is essential because it allows the material to absorb energy and resist fracture, which is particularly valuable in applications where the component may face dynamic loads or significant stress. Therefore, this dual enhancement property—hardness at the surface and toughness at the core—makes this answer especially relevant in contexts where durability and performance are critical.

While corrosion resistance, electrical conductivity, and thermal resistance are essential material properties, they are not the primary focus of the case hardening process. Case hardening specifically targets the balance of hardness and toughness, making it a critical treatment in fields such as manufacturing and mechanical engineering where wear resistance is a major concern.