Magnetic flaw detector

Does Steel Corrode, and How Can Corrosion Be Reduced to Prevent Rust?

Corrosion does not occur only on the surface of steel. It can also develop silently within the metal structure, where small defects may form and gradually propagate over time.

Because of this, in non-destructive testing (NDT), steel corrosion is rarely treated as an isolated phenomenon. Instead, it is closely associated with the initiation and growth of material defects, which directly affect structural integrity and operational safety.

Why Steel Corrosion Must Be Understood in Its True Nature

Corrosion does not always appear as visible rust on the surface. In many steel structures, the process begins at microscopic weak points such as microcracks, areas of stress concentration, or structural irregularities introduced during manufacturing or machining. When steel is exposed to its service environment, these locations become sites where chemical reactions occur more rapidly than in the surrounding material.

Over time, internal degradation gradually alters the mechanical properties of steel. Load-bearing capacity decreases in ways that are difficult to detect through visual inspection alone, especially in thick steel components or parts that are already installed within operating systems.

How NDT Helps Control Steel Corrosion

In non-destructive testing, the objective is not simply to determine whether steel has failed, but to monitor how the material evolves throughout its service life. For critical structures such as pipelines, storage tanks, steel beams, or continuously operating mechanical components, early detection of corrosion-related defects is far more valuable than corrective action after a failure has occurred.

Magnetic particle testing is commonly applied during periodic inspections due to its fast response, clear visual indications, and suitability for ferromagnetic materials. In workshop conditions, handheld magnetic particle inspection systems such as the INSIZE MPI-P110 are used to generate a stable magnetic field, ensure uniform surface coverage, and consistently detect corrosion-related defects.

Magnetic Particle Equipment and Consumables in Steel Corrosion Inspection

The reliability of inspection results depends heavily on the magnetizing equipment and consumables used. When magnetic yokes are combined with dry magnetic powder or fluorescent magnetic suspensions, magnetic flux leakage at corrosion pits or crack locations becomes clearly visible. This allows engineers to accurately assess the extent to which corrosion has affected the internal structure of the material.

In industrial applications, magnetic particle inspection equipment supplied by EMIN supports inspection work from field operations to production workshops. These solutions help engineers identify risks at an early stage and implement appropriate corrective measures before corrosion leads to serious structural damage.

Looking Beyond Corrosion as a Surface Phenomenon

At a broader level, the question of whether steel corrodes leads to a more fundamental issue: how steel changes throughout its operational life. These changes are not always easy to observe, but they can be effectively detected using appropriate NDT methods.

Magnetic particle testing is one of the most effective tools for early risk identification, particularly for load-bearing steel components or equipment operating in harsh environments. When applied correctly, this method serves not only as an inspection technique, but also as a practical solution for extending service life and maintaining safety in industrial steel systems.