Corrosion is a major issue for industrial and commercial businesses, but there are ways to reduce the cost of significant damage. Corrosion assessment services provide evaluation and mapping of corrosion to help companies better understand the extent of the problem. By using corrosion mapping services, business owners can prevent costly damage from occurring and maintain their assets in optimal condition. This article will explain what corrosion is, what can cause it, the various kinds of corrosion, and how to avoid costly damage by utilizing corrosion assessment services.
What is corrosion?
Corrosion is the alteration of a material by chemical reaction with an oxidant. It is characterized by the weakening, destruction or progressive alteration of a certain material. Corrosion occurs when a material deteriorates due to environmental factors.
Corrosion is a natural process that occurs when three factors are present: the presence of moisture, a metallic surface, and an oxidizing agent (also called an electron acceptor). Through this process, the metal is transformed into one of its salts, i.e. oxides/hydroxides/sulfides, depending on the material.
The metal is chemically unstable while its salt is more stable. One of the most common forms of corrosion is rusting. When iron rusts, the reddish flaky substance that forms as a result of the corrosive process is iron oxide.
Causes of Corrosion
In most cases, corrosion occurs when moisture and electrochemical reactions between fasteners and their components take place. When a drop of water touches a flat metal surface and this surface is exposed to the air, the oxygen consumes the surface, and the water drop fails to receive oxygen due to electrochemical differences. An electric current flows through the drop of water, acting as an electrolyte and causing the iron ions to dissolve.
During this process, hydroxide ions are created in the water and interact with the iron ions, resulting in the precipitation of iron hydroxides which subsequently form hydrated iron oxide and, thus, rust.
Types of Corrosion
Crevice corrosion occurs because small holes and corners tend to attract moisture and are poorly ventilated. The risk of crevice corrosion increases with the number of sides of the fitting.
Austenitic stainless steels can develop inter-granular corrosion when heated to high temperatures during hot forming or welding.
The most common type of corrosion is uniform corrosion. It is identified by its reddish color, which is evenly distributed across the affected fastener.
Pitting corrosion occurs on a metal surface with a noble coating such as nickel or chrome. The exposed surface becomes less noble than the surrounding surface which is less exposed to environmental factors. This creates a current density that causes galvanic corrosion in the holes.
Galvanic corrosion occurs when moisture is exposed to two unique metals that do not share the same properties. This happens when electrons move from one metal to the other, creating an electrolytic cell. The electrolytic cell causes one metal to corrode faster than the other, creating an imbalance in the metals and leading to corrosion.
Stress corrosion can occur when corrosion manifests on fasteners that are subject to stress. This type of failure often begins with pitting corrosion.
This is not a type of corrosion; rather, hydrogen embrittlement of a fastener can result from corrosion of a fitting. If high strength fasteners are under stress, small surface defects such as scratches can develop into cracks.
If hydrogen is present in the steel atoms, they are attracted to the tensile stresses near the crack tip and form a “hydrogen atom cloud.” The hydrogen weakens the microstructure of the metal and the crack can grow until the part fails.
Assessing Corrosion Damage
With a combination of design and construction expertise and material science, our engineers at Scan Plus Tech can help you overcome concrete durability problems and improve the resiliency of a structure by finding the root cause of the problem and developing practical solutions that will prolong its life. Corrosion assessment can be conducted in several ways, including the following:
- Corrosion mapping
- Concrete testing and sampling
- Corrosion rate testing
- GPR survey
- Structure monitoring and instrumentation
- Non-destructive testing
- Investigation services of a post-tension system
- Corrosion potential surveys
- Chloride profile testing
Cost and Time Considerations
Without proper care, rust will increase and the internal stresses will grow with it, causing cracks to form at the steel or concrete interface. Over time, the corrosion product accumulates and leads to progressively larger cracks until the concrete separates from the bar, ultimately leading to spalling.
If a steel-reinforcing bar loses more than 20% of its cross-sectional area, it must be replaced during the repair process. The corrosion process, once initiated, deteriorates and distresses the concrete element, exposing its structural integrity. Corrosion assessment services offer an inexpensive opportunity to mitigate problems so the final user can continue to save time and money.
In conclusion, corrosion assessment services are a worthwhile investment for any business. They can help identify corrosion early on, reducing the risk of costly damage. They also offer practical and cost-effective solutions for preventing, controlling and monitoring corrosion. Businesses should choose an experienced provider who provides comprehensive services and who is committed to quality and safety standards.
Regular reviews of existing systems are also recommended to ensure that any potential problems are addressed quickly. Taking these steps can help businesses protect their properties from costly damage associated with corrosion.
Don’t neglect corrosion as it can damage your facility; instead, make the wise decision now and choose Scan Plus Tech’s corrosion assessment services. Our experts will conduct a detailed inspection of your environment, helping you to stay one step ahead and avoid costly repairs or even system failures. Act now to ensure long-term success for your product and the safety of its users!