Low Temperature Carburizing of Austenitic Stainless Steel: Part One

Although austenitic stainless steels are among the most commonly applied corrosion resistant steels challenges exist related to their relatively poor surface hardness and wear resistance.
Low temperature carburizing presents an effective solution to these challenges by increasing surface hardness through a carbon rich diffusion zone which does not compromise the corrosion resistance of the material. Continue reading

Lean Alloy Steels

Rising prices of certain alloying elements such as nickel and molybdenum have driven recent work on lower priced replacements for austenitic stainless steels.
Progress has been made in finding suitable replacements but there are some key open questions remaining regarding the performance of the materials in specific applications. Continue reading

Corrosion Behavior of Copper Alloys: Part Two

Copper and copper alloys are specific in their corrosion behavior in that the initial corrosion rate of this group of materials is relatively high until protective layers form according to the alloy and the composition of the electrolytic solution.
One prime example of a material group which has found widespread use within the marine environment due to its excellent corrosion resistance are the copper-nickel alloys.

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Corrosion Behaviour of Copper Alloys: Part One

Copper demonstrates excellent corrosion resistance in marine environments as well as showing strong abilities to withstand several other key localized corrosion forms which could potentially lead to failure.
Commonly weathered copper will go through a range of visual appearance transformations including the development of a brown patina within a few days of exposure and this will develop into the recognized green color over a period of 7-9 years.

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Corrosion Protection of Steel: Part Two

Metallic coatings provide a layer that changes the surface properties of the work piece to those of the metal being applied. The work piece becomes a composite material exhibiting properties generally not achievable by either material if used alone.
Metallic coatings are deposited by electroplating, electroless plating, spraying, hot dipping, chemical vapor deposition and ion vapor deposition.

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Corrosion protection of Steel

Corrosion of steel is an electrochemical reaction that requires the presence of water (H2O), oxygen (O2) and ions such as chloride ions (Cl), all of which exist in the atmosphere. Electrophoretic deposition is a process in which electrically charged particles are deposited out of a water suspension to coat a conductive part. The process is more commonly known as electrocoating or E-coating.

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Hydrogen Sulfide Corrosion

Hydrogen sulfide corrosion and its prevention is an important topic in a range of industrial processes and environments including oil and gas and its related activities.
Mild steel is a popular structural steel in this industry but is susceptible to surface scale formation and associated corrosive action, the prevention of which requires some special methods.

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Corrosion of Aluminum and Its Alloys: Forms of Corrosion

Corrosion is the chemical reaction of a metal, in this case aluminum, with its environment, which leads to the deterioration of the properties of metals, aluminum in this case. Aluminum is a very reactive metal, but it is also a passive metal. This contradictory nature is explainable because nascent aluminum reacts with oxygen or water and forms a coherent surface oxide which impedes further reaction of aluminum with the environment.

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