Intergranular corrosion can lead to catastrophic failure in equipment if proper material and treatment haven't been used during the fabrication stage. T here is considerable corrosion damage, such as uniform corrosion and pitting corrosion, that people can easily see with the naked eye. However, some  corrosion damage  is not visible while still being harmful to the structure or equipment integrity. This article will take a better take a look at one of the less  visible corrosion damage types  called intergranular corrosion (IGC), with a concentrate on developing a much deeper understanding of how intergranular corrosion happens, what materials are impacted, the kinds of markets where  intergranular corrosion  generally happens, and how to spot and reduce the damage. What is Intergranular Corrosion (IGC)? Intergranular corrosion (IGC), sometimes described as an intergranular attack (IGA), is a preferential or localized corrosion profit alone the grain (crystal) borders or right awa

A pipeline coating is a low-cost solution to maintain pipeline integrity. Polyurea coatings present a constant protective lining that helps save pipelines from the damaging results that corrosion produces. Pipeline coatings are one of the most reliable corrosion prevention methods used within the industry today. Understanding What Pipeline Coatings Are Pipeline coatings are typically used to counter the adverse effects of corrosion on pipeline operation, capacity, and costs.  Uncoated pipelines that are immersed in seawater are prone to corrosion. Although the corrosion debris from these pipelines can be removed, the disposal of these fragments can be detrimental to the environment. Therefore, strict regulations have been implemented, including the practice of implementing pipeline coatings . This hinders the formation or reformation of corrosion. Pipe coating applications are regarded as a standard practice and present the following benefits: Improved gas flow  - A smoother surfac

Chloride and galvanic and acidic or alkaline corrosion could create Corrosion in the Insulation (CUI). However, an understanding of the types of Corrosion and preventative measures can reduce the risk. Corrosion is a major cost to the global economy, costing approximately $2.2 trillion every year as per the World Corrosion Organization. From that figure, it's estimated that between 40 and 60 percent of maintenance costs result from Corrosion in the Insulation (CUI). Corrosion in Insulation is a mysterious phenomenon that is often not noticed. It is due to practical reasons. (For more information on inspection methods, refer to The 4 Most Effective Nondestructive Inspection Methods to Check Corrosion under the Insulation.) It isn't always possible to use the ideal insulation coating combination or apply the most efficient inspection methods. The intruding of water is the main cause of the development of CUI. Corrosion can attack or damage the jacketing and the insulation hardwa

Presently there are several renewal options available for various applications, and l inings and coatings are mostly used for the renewal of water pipes. These coatings and linings are most commonly used to renew water.   Polyurea is one of the most popular coatings and linings. The lining material is applied to the inner surface of the deteriorated host pipe with a spray method.  It can be used to strengthen the structural integrity of the pipe, and also provide a protective coating.   This thesis describes the  preliminary results from an ongoing testing program in the laboratory intended to study the possibility of a renewal Potable pipes by using polyurea spray for the lining.   This research is focused on forecasting the future of long-term use  the behavior in terms of polyurea term behavior of polyurea.   The objective in this study was to determine the relationship between polyurea composite and its behavior  between strain, strain and time.   The results from the tests have be

W hile galvanic corrosion is a serious threat and understanding why it occurs can make avoiding this typical corrosion type much simpler. C orrosion is a vital concern when selecting piping materials and developing piping processes. While stainless steel is highly resistant to many forms of corrosion, being mindful of dangers is necessary to the safe, long-lasting operation and reducing expenses over the life of your system. In this guide, we'll discuss galvanic corrosion, where and when it might happen, and how you can reduce the threat of or avoid galvanic corrosion when utilizing stainless steel pipe. WHAT IS GALVANIC CORROSION? Also known as bimetallic corrosion or dissimilar metal corrosion, galvanic corrosion is when corrosion damage occurs due to two dissimilar metals coupling in the existence of an electrolyte. So, breaking that down, it indicates three conditions must be satisfied for galvanic corrosion to end up being a concern: Several metals need to be present with vary

M odern construction materials have several well-defined mechanical properties that can tell us a lot about their characteristics and performance when used in construction. However, the story is far from concluded because of newly acquired materials whose behavior is still unexplored. We discover new damage mechanisms as we create more advanced applications with new environments and methods of operation. Most of these properties are defined microscopically, but their true nature is best understood on a macroscopic level through numerous mechanical tests and, unfortunately, experience. These tests are ordinarily conducted using standardized test specimens and test equipment that give us accurate assessments of various characteristics we define, such as material strength, toughness, hardness, resilience, and flexibility. These properties are respectively dependent and only have used in helping us describe the different qualities – they are not separate, independent mechanical properties.

  C orrosion refers to the tendency for metals to return back to their original condition. Contact with vapors, gases or other liquids can lead to a chemical reaction. The dry environment reaction is often associated with high temperatures. In liquid atmospheres that are sprayed or submerged, an electrochemical reaction or humid-environment reaction occurs. Corrosion  is a process that returns materials to a  thermodynamically stable condition  by their interaction with other substances in the environment, especially oxygen. This is the state in which the materials are transformed by the  metallurgic process . Technology's most popular metals have a high affinity for oxygen. Their corrosion process is solely dependent on "oxidation". Some metals are more susceptible to oxidation than others. Because of their low affinity for oxygen, metals such as gold and platinum are very resistant to oxidization. Iron, for example, oxidizes easily because of their high affinity to oxyg

Filiform corrosion  is a distinct form of corrosion that occurs under thin  coatings  in randomly distributed threads like filaments. Filiform corrosion is also identified as under film corrosion, filamentary corrosion, or worm track corrosion. This article explores the causes of filiform corrosion, where it typically appears, how it develops, how to identify it, and how to stop it from occurring. What is filiform corrosion? Filiform corrosion occurs on metallic surfaces covered with a thin organic film, typically 0.05 to 0.1 mm (2 to 4 mils) thick when revealed to warm, humid atmospheric air. Filiform corrosion always begins at coating defects such as scratches and weak features such as beards, cut edges, and holes.  How Filiform Corrosion Occurs In many regards, filiform corrosion on aluminum (Al) and magnesium (Mg) is similar to corrosion on steel. Filiform corrosion is driven by the formation of differential aeration cells at defect sites on coated substrates. The filiform cell co

Takeaway: Polyurethane and polyurea coatings represent an outstanding alternative for numerous applications; however, the treating time attributes and the versatility of the application procedure are important factors when considering each type. Several methods are employed to protect metallic elements from deterioration due to serious environmental conditions, such as the effects of high humidity, seawater, heat, and chemical attacks, to name a few. Within these methods, it is extremely common to use coating systems. This article offers a basic summary of the appropriate differences between 2 protective coating products: polyurea and polyurethane. The Chemistry of Polyurethanes and Polyureas Polyurethanes and polyureas are polymers regularly used to produce protective coatings and linings. Both are based on a two-component system, and the treating systems are by co-reaction, where isocyanate is a typical part. The 2nd part is a polyether polyamine for polyureas, while polyether poly

This figure shows several heating cycles on a hanging steel sample. The steel sheet was heated at a rate of 5 K/min in a nitrogen atmosphere with 16% oxygen. Oxidation (mass increase) decreases with each subsequent heating cycle. At the beginning of the test, oxidation of the sheet surface occurs. This can be observed in the early onset and rapid mass increase for the first heating. After a couple of heating cycles, inner oxidation occurs, which is indicated by a slower, diffusion-dependent mass increase. I n this article, we'll examine corrosion products produced by high-temperature exposures and explain how this information can be used in corrosion prevention. Because high-temperature corrosion tends to produce scale that is multi-layered, line scans and spot maps may be used to illustrate the multi-layers but these techniques are qualitative. They rely on displaying total counts; density of the location can impact the results. Thus, it is also useful to supplement these analyse