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Electrochemical testing - part 3- What does an ammeter do?

 Electrochemical testing - 3 - Ammeter Poll Question WITH Answers: Description: Tafel polarization is a potentiodynamic test, where the potential is changed at a certain mV/time rate. The changes in the current flow occurring due to the potential change are measured using the ammeter. The ammeter is connected between the working electrode and the counter electrode. It is NOT connected to the reference electrode in any way . Check out the video for a detailed explanation Check out the previous parts here - PART 1 PART 2 For concise and focusSed courses, check out the website below! https://corrospective.com

3 Stages of the beginning of your PhD...aka...OMG what the H am I doing here?

PhD is not a goal, PhD is a journey, and a mighty transformative one at that. That it has different stages is a known fact. However, just the beginning of the PhD has different sub-stages. The pre-beginning the admit and preparation to leave There is fear of the unknown as well as the excited anticipation of new places and people. Specifically in case of Indian students, the flurry of bag packing is accompanied with homemade pickles and snacks. The beginning orientation and settling in The students at this point in time are faced with a bit of anxiety and struggle while searching for accommodation (for overseas universities). There is the factor of being so far away from the family for the first time. Then there also is the undercurrent of being able to manage finances and household chores. A very busy phase indeed. The post-beginning where the students settle into their research groups and begin the literature review. Some may also begin small experiments. There is the enthusiasm of l...

Corrosion in daily life - Blistering

All of us corrosion people head out of the house to work on coatings. And yet, we leave so many types of coatings behind in our house. The most commonly seen commodity is an electric box with switches. Usually they are coated.  This is an example of such an electric box. It shows blisters formed in the white coating. Such blistering occurs when water penetrates the pores in the coating.  Usually such parts do not come under the 'critical' category. Hence, the coatings are not very thick. Moreover, there is no coating inspector involved during the application. As a result, they are prone to early degradation. However, their position plays an important role in determining this time frame. Those boxes present outside the hose are exposed to the heat and cold. Usually they will be in a shaded area. So, they may not face the rain directly. Some boxes are inside the house in rooms. Those face the least coating damage. The image above is from an electric box in a bathroom...

Practice quiz for coatings - 1

Practice, practice, practice... and you shall gain the certificate! So here goes a new series, where I will post quizzes on various corrosion and coating topics. This is for anyone who likes quizzes, and ESPECIALLY for those attempting exams! So here goes the first one!  Subscribe to this blog for updates!  Loading…

To being a corrosion 'nerd'

I am someone who loves to study. This may sound 'nerdy'. In fact, someone called me that once. I was almost 22 and even then I was OFFENDED. Hah! This is something so many of us have struggled with. In fact, just to not be a 'nerd', there are people who have simply stopped studying as much as they used to. After all 'OMG, you study so much!' is not really 'cool' after a certain age. Not anymore! I have learned that everyone is 'nerdy' in their own way, even those who pride themselves of being 'laid back' and proceed to call others 'nerds'.  So, here's to you, the sports lover. YES, I am looking at you. If you can mouth off the statistics for your favourite team, you are a nerd, only a sports one. In fact when I get hold of a magazine for corrosion, I have to take a deep breath and choose which article to read. Obviously, I want to read all the articles at once! There is so much to learn, especially in terms of scie...

Corrosion rate and pipe design

Corrosion is a serious issue. However, corrosion engineers are rarely asked about it during the designing of components. It is only when the components fail that people remember there are people who have studied corrosion for their whole life and would provide a solution. The design problems are really quite simple, and the loss of money could have been avoided had the company bothered to involve a corrosion engineer in the first place. Let me illustrate this with an example of a factory near the sea. Suppose a mild steel pipe is fitted inside the factory to transport 1 wt. % hydrochloric acid. The engineer has a choice between selecting pipes of 5 mm and 10 mm thickness. To save money, they go for the pipe with the 5 mm thickness because it has been 'successfully used by the other customers'. Over the course of a year, it is seen that the pipe has started leaking at certain places. Further investigation reveals that those sections have thinned to half of their thickn...

The drain mystery

I recently moved to a new house. As expected, there was a lot of cleaning up to do. One of the tasks was the cleaning of the washbasin. Usually, the drain is a circular part with  5 to 6 holes for the water to flow out. What I saw was this - I have not had a chance to analyse the material of the drain. However, a quick search tells me that this is most probably stainless steel. The water that this drain is exposed to is the bore water. Thus, the drain has encountered a lot of chlorides. There is general as well as localized corrosion. The damage started off as a simple process of pitting. Pitting due to chlorides is one of the most common headaches for poor stainless steel. They break the passive oxide film, and reach the underlying fresh iron. This iron then reacts with the usual suspects (ions, oxygen, water) and forms what we see as the rust. As can be seen in the picture, the thin sections of the drain between the holes have disappeared in three places. This may have h...

Corrosion - the bane of all the industries

Corrosion is the journey of an element from its most active form to its most stable form.  The birth At the place of its birth, inside the earth, an element such as iron comes into contact with atmospheric oxygen, chlorides, sulphate, and moisture. and is quite happy to remain in peace with them in the form of Fe 2 O 3 , Fe 3 O 4 , FeCl 3 and such. The growth It is then extracted and made to go through a number of processes which separate it from the ions and bring it to its elemental form. It is then put into use to make steel, where it coexists with carbon, manganese, chromium, and other alloying elements. The interaction However, iron has three electrons that it desperately need to give away. That is exactly what it does the moment the steel is brought out from the factory and put outside in the shed. Iron is more than happy to reunite with its old buddies - oxygen and moisture. It gladly gives away its electrons to them and returns to its peaceful state of Fe 2 O 3...