Corrosion, although invisible to the naked eye in its early stages, is a latent threat that can undermine the durability and safety of infrastructure and materials. It not only threatens physical integrity, but also has a considerable economic cost for businesses and society.
While corrosion is a natural and unavoidable phenomenon, its detection and proactive management have become a priority, especially in regions like Quebec, where extreme climatic variations accentuate its impact.
In this article, we delve into the complex world of corrosion, its effects, and the crucial importance of professional detection in countering its devastating effects.
What Is Corrosion?
Corrosion is the destruction or deterioration of a material due to a reaction with its environment. The term can refer to a process or to the damage caused by such a process.
Although different types of material are affected by corrosion, iron is the most common victim. When iron is exposed to oxygen and water, the result is a red iron oxide commonly known as rust.
Iron rust generally forms when iron reacts with oxygen in the presence of water. Alternatively, under certain conditions, notably in the presence of chlorides, iron can react to form greenish compounds such as ferrous chloride. It should be noted, however, that these reactions are more complex and may depend on specific exposure conditions.
What Types of Corrosion Exist?
Many types of corrosion exist, and we’ll briefly review them below.
Uniform corrosion is the most common form, typically occurring over large areas of a material’s surface in a uniform pattern.
Pitting corrosion occurs when local anodic or cathodic points interact with the surrounding surface, forming a corrosion cell. This interaction creates a cavity or hole that extends vertically into the material from the surface. Although the amount of metal lost may seem small, this form of corrosion is particularly dangerous, as it can lead to structural failure.
Crevice corrosion occurs mainly in areas of low oxygen content, often due to a difference in ionic concentration between two metal regions. This imbalance leads to increased corrosion rates.
Intergranular corrosion occurs in the presence of impurities localized at the grain boundaries formed during the solidification of an alloy. This type of corrosion can also be caused by the enrichment or depletion of an alloying element at grain boundaries. It has a negative impact on the metal’s mechanical properties.
Corrosion cracking refers to the progression of cracks caused by a corrosive environment, leading to the failure of ductile metals subjected to tensile stress.
Galvanic corrosion occurs when two different metals, in direct or electrical contact, are immersed in a single electrolyte, or when a single metal is exposed to different concentrations of the same electrolyte.
Now that we have defined corrosion and identified its major types, let’s explore the importance of detecting corrosion.
Corrosion detection is the process of identifying factors that result in the corrosion of materials subjected to standard atmospheric conditions. This process is crucial for assessing the materials’ ability to withstand existing environmental factors.
Means of Detecting Corrosion
There are several standard ways to detect corrosion:
This is a fast, non-contact method of detecting corrosion. The process relies on thermal variations between materials and their inherent defects to visualize these anomalies, including corrosion. Reflected thermal waves are used to estimate the level of corrosion, higher intensities being synonymous with increased corrosion rates. The practical applications of this technique have been greatly enhanced in recent years, thanks to the evolution of algorithms and improvements in the instruments available on the market.
This method is particularly effective for detecting corrosion in electrically conductive materials. To assess a material’s resistance to corrosion, a probe coil is used. Increased intensity of eddy currents induced in the material is indicative of a higher corrosion rate.
Although this method of corrosion detection may involve dismantling systems and testing in an aquatic environment, it is recognized as one of the most accurate techniques for identifying corrosion.
Perhaps the most effective method of corrosion detection is by means of GPR, or ground-penetrating radar.
Most non-destructive detection methods are difficult and highly localized, tending to produce incomplete results. To obtain a more thorough analysis, the use of ground-penetrating radar is ideal.
A non-destructive technique for detecting corrosion, GPR manages to cover a large area of study whereas other means of detection are restricted to small areas or specific points
The Importance of Corrosion Detection
There are several reasons why corrosion detection is important.
Corrosion detection is especially important in industries that work with volatile materials that could explode if not properly stored. As materials age, they become more susceptible to corrosion and less resistant to factors such as temperatures and high pressures. By using corrosion detection methods such as GPR, potential problems can be identified before they pose a safety hazard.
Cost control is essential for any business, and corrosion detection makes a major contribution to this. Without proper corrosion monitoring, materials and equipment deteriorate prematurely, requiring costly replacements that disrupt operations and strain budgets.
By detecting and preventing corrosion at an early stage, we can not only extend the life of materials and equipment, but also make significant savings.
Corrosion detection can also increase the efficiency of operations in a number of ways. Not only can it extend the lifespan of materials and equipment, if can provide insight into the type of materials that are less likely to corrode, resulting in wiser acquisition of future assets.
Furthermore, it can help identify conditions in the work environment that create or mitigate corrosion, allowing one to make informed purchasing or maintenance decisions.
Finally, corrosion detection can increase efficiency by reducing facility shutdown time. When crucial equipment fails due to factors such as corrosion, the workplace must temporarily shut down until the affected equipment is repaired or replaced. This leads to significant, and unnecessary, periods of inefficiency.
Why Corrosion Detection Is Especially Important in Quebec
Corrosion detection is especially important in Quebec due to the province’s temperature extremes and frequency of precipitation. Summers are extremely hot and humid, with temperatures often reaching 30 degrees Celsius; winters are exceedingly cold and long-lasting, with temperatures regularlhy dipping below 30 degrees Celsius. Such extreme temperatures and precipitation (humidity in the summer, and snowfall in the winter) greatly affect materials, causing high levels of corrosion.
The Need for Professional Corrosion Detection
As we’ve established, corrosion is a multifaceted form of destruction that has a serious impact on a variety of materials. It can lead to increased safety risks, costs and periods of operational inefficiency.
To reduce and prevent the destructive impact of corrosion, it is necessary to call on the services of companies experienced and equipped to deal with this type of problem. It is particularly useful to call on companies that use the highly effective method of georadar, or ground-penetrating radar, to detect corrosion.
In all environments, but especially those prone to precipitation or severe temperature variations, such as the province of Quebec, corrosion detection is crucial.
Fortunately, there are professionals on hand to help. Don’t let corrosion compromise the safety and efficiency of your structures. Call on Scan Plus Tech today and benefit from unrivalled expertise to protect and extend the life of your assets.