Imagine machining a piece of steel. A cutting tool with hard, sharp inserts produces clean steel chips while consuming relatively little energy. If the tool’s inserts were soft and had rounded edges, much more energy would be needed to remove the same amount of steel. This example highlights the difference between the effects of hard, sharp abrasives and soft, rounded ones.

When rounded rocks or minerals slide across a steel surface, the energy is primarily used to deform the groove rather than cut into the steel. In such cases, a tough material can absorb significant deformation energy before steel debris is removed from the surface.

Cutting deformation.

Measuring hardness

The Brinell hardness test (HBW) is the most efficient way to measure steel hardness. Its key advantage lies in applying a high load over a large area, which minimizes variance even when the steel surface is machined or rougher than polished. In contrast, methods like Vickers and micro-Vickers require a polished surface and are typically used for research purposes, since they demand more extensive preparation of the steel surface.

Hardox^® wear-resistant plates are classified by their average typical Brinell hardness values, such as Hardox^® 400, Hardox^® 450 and Hardox^® 500.

A conversion table for Brinell and other hardness measurement methods is provided in the table below.

No standard correlation exists between these three hardness testing methods or their relationship to tensile strength. The data provided thus serves as guidance, derived from extensive in-house measurements of Hardox^®.