Types of MARINE corrosion

Types of MARINE corrosion

The marine environment is one of the most corrosive environments. 

Its corrosivity is due to the ionic concentration of the seas and oceans, temperature variations, wind velocities, depth of the sea, and biological elements.

As a result, the corrosion on marine structures such as ships, FPSO, and offshore platforms, appears in multiple forms.

Hence, it is important to learn about the basic types of corrosion as applicable to the marine environment.

Some of these types of corrosion in a marine environment are –

  • Uniform corrosion due to sodium, magnesium, and calcium salts
    • Uniform corrosion is characterized by the removal of the material all over the surface. It leads to thinning of the walls.

  • Pitting in active-passive alloys such as aluminium
    • Active-passive alloys have a thin oxide film on the surface. A small break due to the chlorides in the seawater allows the penetration of the water and ions, leading to pit formation.

  • Crevice corrosion in fixtures and subsea pipeline supports
    • The seawater and moisture from the atmosphere get into the gaps in the fixtures and supports due to capillary action. Oxygen concentration cells are created in these crevices which initiate corrosion.

  • Stress corrosion cracking in loaded elements
    • Parts of the equipment such as anchors, legs of offshore platforms, propellors, etc. are under a constant tensile load. This stress combined with the pits formed on the surface causes cracks and failure of the components.

  • Hydrogen embrittlement in cathodically protected areas
    • Cathodic protection is the application of a negative potential to the component to protect it from corrosion. However, if it goes too negative (more negative than -1 V vs CSE), the cathodic reaction is hydrogen evolution. the hydrogen so generated can penetrate into the components and damage the mechanical integrity.

  • Microbiologically influenced corrosion
    • Seawater has tons of microbial activity in addition to algae and weed formation in the submerged areas. The microbes take up electrons from the alloys for their food production and lead to the dissolution of the material.

  • Atmospheric corrosion of metallic structures along the shore
    • Due to the spraying of seawater, the marine atmosphere has salt in the air. This salt may get deposited on surrounding structures in the dissolved state during moisture condensation. It can cause pitting in stainless steel components due to the chloride ions.

  • Cold corrosion of marine engines
    • Cold corrosion in marine engines occurs when the engine is running at low loads leading to a condensation of moisture at reduced temperatures. The sulphur in the fuel gets dissolved and causes corrosion.

Although they seem the same as any other corrosion area, it is essential to study their basic mechanisms as applicable to marine materials and environments.

The video below shows a preview of the introductory course on the types of corrosion in the marine industry.

Click below for the course! 



Self-plagiarism..aka..Can I copy paste my own stuff in my research paper?

As students and professionals, report/thesis writing is an important task that requires quite a bit of effort. If we are into publishing our work, we have to be more careful as to how we arrnage and present out work.
Usually we tend to write several reports and some of the material may overlap.
With the new plagiarism software, one may doubt whether we can directly use our work. After all we wrote it.
Plagiarism can be a direct copy-paste from your own previous work or from literature. It is a serious issue especially because it is now easy to do it using software.

There are two main points to remember in this case.
Point # 1Copying from your own previous work.
When writing a manuscript which has experimental, theoretical, or mathematical components from a previous work of your own, avoid using entire sections verbatim.
Such instances may show up as plagiarism during checks by the publishers. There is also a noticeable difference between the language of these sections and that of the rest of the new manuscript. Hence, ensure that at least the sentence construction is modified, even if the procedure and explanation are supposed to be identical to those in the previous publication.

Point # 2 – Copying from other sections in the same manuscript

Avoid copy-pasting sentences from the main text to make up the abstract and the conclusions. Such copy-pasting is very easy to detect and it indicates two things –
(1) The author does not know the difference between abstract, main text, and conclusions.
(2) The author is too lazy to actually use different sentence structures to rephrase their ideas.
These points are very evident and reviewers are quick to notice them. Hence, it is better to find a way around these errors.
Check out the video for a detailed explanation! –



For the DESKTOP EXCEL version of the template, comment on this post!

Comment your questions and feedback!

How many pages long should my research paper/thesis be?

In this post, I would like to address an issue that is encountered by many undergraduates and postgraduates who are doing their very first research project.

In my experience of designing and managing projects for undergraduates, interns, and postgraduates, I so often get asked two questions –

1) “How many pages should my research report/thesis/paper be?”
2)”How many references should I put at the end of the paper?”

My answer is stop focusing on the number unless it is a strict requirement. Base your report on what you have learnt in the research work. Concentrate  on describing the amazing new things that you have got acquainted with.

At each step of the project, you will come across a small question leading to reading of new references, and you will not need to find more just for the sake of it.

Enjoy the process of writing something you found amazing.

Check out the detailed video below!



For the DESKTOP EXCEL version of the template, comment on this post!