Category: ‘Corrosion’
Galvanic corrosion occurs when two dissimilar metals with different potentials are placed in electrical contact in an electrolyte. It may also take place with one metal with heterogeneities (dissimilarities) (for example, impurit... Read More...
SCC is a form of corrosion which occurs with a particular combination of factors:
Tensile stress
Corrosive environment
Sufficiently high temperature. Normally 50 deg C but can occur at lower temperatures around 25 deg C... Read More...
The range of duplex steels allows them to be matched for corrosion resistance with the austenitic and ferritic steel grades. There is no single measure of corrosion resistance. However, it is convenient to use the Pitting Resista... Read More...
This type of anode supports other anodic reactions on their surfaces. In environments where water and chloride ions are present, chlorine evolution and oxidation of water are possible.
Platinized substrates: Platinum is t... Read More...
The following Figure illustrates the E-pH diagram for iron in the presence of water or humid environments at 25oC, which was calculated by considering all possible reactions associated with iron in wet or aqueous conditions l... Read More...
The E-pH diagram of aluminum is one of the simplest E-pH diagrams. It will be used here to demonstrate how such diagrams are constructed from basic principles. In the following discussion, only four species containing the alum... Read More...
Brass resistant to corrosion in many media. Brasses are particularly susceptible to corrosion by solutions containing ammonia or amines. Alloys with more than about 15% of zinc may suffer dezincification, which leaves a weak,... Read More...
Walther Hermann Nernst was born in Briesen, West Prussia, on June 25, 1864. His father, Gustav Nernst, was a district judge. He spent his early school years (Gymnasium) at Graudentz, and subsequently went to the Universities of ... Read More...
The Nernst equation was named after the German chemist Walther Nernst who established very useful relations between the energy or potential of a cell to the concentrations of participating ions. This equation can be derived from... Read More...
In 1681, accelerated corrosion having been observed between iron and lead sheathing, the Navy Board decided locally to remove the lead sheathing from ships' hulls to prevent the rapid corrosion of the rudder irons and bolt hea... Read More...
Impressed current cathodic protection is applied by coupling the metal to be protected to the negative pole of a direct current (DC) source (schematic), while the positive pole is coupled to an auxiliary anode. Since the drivi... Read More...
The first application of cathodic protection (CP) can be traced back to 1824, when Sir Humphry Davy, in a project financed by the British Navy, succeeded in protecting copper sheathing against corrosion from seawater by the ... Read More...
The cost of cathodic protection of metallic structures subject to corrosion can be divided into the cost of materials and the cost of installation and operation. Industry data have provided estimates for the 1998 sales of various... Read More...
CP-Cathodic protection was born in 1824, when Sir Humphry Davy made a presentation to the Royal Society of London: "The rapid decay of the copper sheeting on His Majesty's ships of war, and the uncertainty of the time of its d... Read More...