I decided to go ice skating this year. She took it out of the closet and saw that the blade of the skates was covered with some kind of red-brown coating. At first I was upset, because my skates were damaged and, probably, they could no longer be skated.
In the evening, my mother came home from work, and I told her about my trouble. Mom reassured me and explained that the blades of the skates are made of iron. And it sometimes becomes rusty if moisture gets on the iron.
I became interested:
-What is rust?
-Where does it come from?
- Do other materials besides iron also rust?
I thought perhaps rust is some kind of red-brown paint that covers all materials over time. To test my assumptions, I decided to conduct some experiments.
1. I took a piece of wood, iron, plastic, glass, fabric and wetted them with water. Two days later, I found that water had evaporated from pieces of fabric, wood, plastic, glass and they were not covered with rust. And on the surface of a piece of iron, a red-brown coating appeared.
So we can conclude:
Non-metal objects - made of wood, plastic, glass, fabrics do not rust, and metal ones - rust.
Then I had another question:
Do all metals tend to rust?
Dad brought me pieces of copper, aluminum, iron, cast iron.
I assumed that all metals rust. To test this hypothesis, I conducted the following experiment:
2. I took pieces of copper, aluminum, iron, cast iron, wetted them with water and watched them for several days. I saw that the surface of iron and cast iron was covered with rust, but the surface of copper and aluminum was not rusty.
So I came to this conclusion:
Not all metals rust. Iron and cast iron will rust, but copper and aluminum will not.
And I wonder if only iron rusts from water or can it be other liquids?
3. I assumed that not only from water. To confirm or refute my assumption, I took: cologne, acetone, vegetable oil, gasoline and four identical pieces of iron. I soaked everything with the indicated liquids. Watched this process for several days.
As a result, I saw that the pieces lubricated with oil, gasoline, cologne, acetone did not rust. This means that iron does not rust from other liquids.
So what is rust?
The chemistry teacher explained to me that rust is a guide iron oxide three. She told me that iron, being in the open air, quickly rusts. This happens even faster if it comes into contact with water. Iron and oxygen in the water begin to interact and form hydroxide, that is, rust. The water becomes reddish and the rust floats in the water as small particles. When the water evaporates, rust remains on the surface of the iron, forming a reddish layer.
On the Internet, I learned about ways to deal with rust, because it corrodes and destroys iron surfaces. To avoid this destructive process, iron surfaces are coated with paint, varnish, enamel, varnish and other stainless metals (chromium, zinc).
And I decided to check it out.
4. I took three pieces of iron: half of the first - painted with paint, half of the second - with varnish, half of the third - cleaned the galvanized layer. I soaked them in water and watched. A few days later, I saw that those iron surfaces that were coated with varnish, paint, zinc were not subject to rust, and the uncoated areas were rusty. I am convinced that such methods of dealing with rust help to avoid the destruction of metal surfaces.
Therefore, the roofs of houses are covered with paint or stainless metals, bathrooms and metal utensils are covered with enamel, washing machines and refrigerators are made of stainless metals; cars and trucks are painted with paint and varnish.
Conclusion:
As a result of research work, I learned what rust is, where it comes from, and what coating methods are used to avoid destruction and preserve the original appearance of iron surfaces.
My advice to adults and children: when the winter is over, wipe the skates, grease the blades with machine oil, carefully wrap them in paper and put them in the closet. So you can keep the blades of the skates for a long time and enjoy the charm of skating next year!
The concept of strength is often associated with metals. “Strong as steel” - each of us has heard this phrase more than once. In fact, under the chemical influence of the external environment, metals can oxidize and break down.
The term "corrosion" comes from the Latin "corrodere" - to corrode. But not only metals are susceptible to corrosion. Plastics, polymers, wood and even stones are also susceptible to corrosion.
Corrosion is the result of the chemical action of the environment. As a result of corrosion, metals are destroyed spontaneously. Of course, metals can also be destroyed under the influence of physical impact. Such processes are called wear, aging, erosion.
Despite the fact that polymers, ceramics, glass are widely used in industry and in everyday life, the role of metals in human life continues to be very important.
We encounter corrosion of metals very often. Rusty iron is the result of corrosion. It must be said that many metals can corrode. But only iron rusts.
What happens to metals during corrosion from the point of view of chemistry?
Chemical corrosion
The surface layer of the metal interacts with atmospheric oxygen. As a result, an oxide film is formed. On the surfaces of different metals, films of different strength are formed. Thus, aluminum and zinc, when interacting with oxygen, form a strong film that prevents further corrosion of these metals. The protective film of aluminum is aluminum oxide Al 2 O 3. Neither oxygen nor water can penetrate through it. For example, in an aluminum kettle, boiling water does not affect the metal.
But some metals and their compounds form loose films. If you cut off a piece of metallic sodium, you can see how a cracked film appears on its surface. Such a film will freely pass oxygen from the air, water vapor and other substances to the surface. Sodium corrosion will continue.
Chemical corrosion is a chemical interaction between a metal and the external environment, which results in the oxidation of the metal and the restoration of the corrosive environment.
But the environment contains not only oxygen and water vapor. Oxides of nitrogen, sulfur, carbon are found in the air, and salts and dissolved gases can be found in water. And the process of corrosion is a rather complicated process. Different metals corrode differently. For example, bronze is coated with copper sulfate (CuOH) 2 SO 4 , which looks like a green cobweb.
Corrosion that occurs under the influence of electric current is not chemical. It is called electrochemical.
Why does iron rust?
Why does iron rust anyway?
During corrosion, the metal oxidizes and turns into an oxide.
The simplified iron corrosion equation looks like this:
4Fe + 3O 2 + 2H 2 O \u003d 2Fe 2 O 3 H 2 O
2Fe 2 O 3 H 2 O - hydrated iron oxide, or iron hydroxide. This is rust.
As can be seen from the reaction equation, rust forms on the surface of iron if it interacts with oxygen in water or moist air. In a dry place, iron does not rust. The rust surface does not protect the iron from further exposure to the environment, so eventually the iron will completely turn into rust. Rust refers to the corrosion of iron and its alloys.
Chemical corrosion is gas and corrosion in non-electrolyte liquids.
Types of chemical corrosion
Gas corrosion is the process of destruction of the metal surface under the influence of gases at high temperature. The most well-known corrosion when exposed to oxygen on the metal.
Chemical corrosion of metals and their compounds can occur in non-electrolyte liquids. Non-electrolyte liquids - phenol, benzene, alcohols, kerosene, petroleum, gasoline, chloroform, molten sulfur, liquid bromine, and others. These liquids do not conduct electricity. In their pure form, they do not contain impurities and do not react with metals. But if impurities get into them, then the metals in such liquids begin to undergo chemical corrosion.
To protect metal structures from chemical corrosion, coatings are applied to the surface, which will provide protection from the effects of a corrosive environment.
THE FIRST OF THEM IS METEORITE, AND THE SECOND IS ASTEROID-TERRESTRIAL
The unique iron Kutub column in India, which has not rusted for more than a thousand years!!!
In India, on the territory of the Qutub Minar complex in Delhi, there is one of the most mysterious objects in the world - the famous Iron Column. It is called the Qutub column, or Maharsuli column. It should be attributed to one of what is now commonly called "wonders of the world", because modern science cannot explain the very fact of its existence, otherwise than by a miracle. In the form in which it is, it simply cannot exist!
There is a Sanskrit poem on this column that says that this column was placed during the reign of King Chandragupta II of the Gupta dynasty, who reigned between 381 and 414 years. ad. Although this does not confirm that the column was made during this period, it is possible that the column itself was made much earlier, and the inscription was applied later. Today, the Kutub column is perhaps one of the most mysterious monuments of Indian culture.
Initially, the Iron Column was crowned with the image of the mythical bird Garuda, dedicated to the god Vishnu and was located in another place in India. Later, the Muslim conquerors, not really understanding what they were dealing with, moved it to the courtyard of the Kuvwat ul-Islam mosque. Most likely, it was then that the Garuda bird disappeared from the column and where it went is unknown.
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THE KUTUB COLUMN HAS THE FOLLOWING CHARACTERISTICS: IT IS MADE FROM PURE IRON, IS ONE-SINGLE, THAT IT DOES NOT HAVE A SINGLE WELDED OR ANY OTHER CONNECTING SEAMS, HEIGHT - 7.3 METERS, WEIGHT - MORE THAN 6.5 TONS; DIAMETER AT THE BASE - 42 CM, DIAMETER AT THE TOP - 30 CM .. BUT THIS IS NOT THE MOST INTERESTING IN THE WORLD
THERE ARE MUCH BIGGER RELIGIOUS OR SYMBOLIC REALIZATIONS. GENERALLY, IN THE TROPICAL AND VERY HUMID CLIMATE OF INDIA, IRON OBJECTS RUST VERY FAST, BUT CORROSION THIS COLUMN
COMPLETELY NOT AFFECTED - IT WAS STANDING FOR MORE THAN 1500 YEARS (WHICH IS DOCUMENTED) AND DOES NOT HAVE THE SMALLEST TRACES OF RUST. NO! AS IF IT IS NOT IN A HUMID ATMOSPHERE, BUT SEALED IN AN AIRLESS FLASK. (ENCYCLOPEDIA).
WHY IS IRON RUSTING?
If you leave some iron object in a damp and damp place for several days, it
covered with rust, as if it had been painted with reddish paint.
What is rust? Why does it form on iron and steel objects? Rust is
iron oxide. It is formed as a result of the "combustion" of iron when combined with oxygen,
dissolved in water.
This means that in the absence of moisture and water in the air, there is no dissolved in water at all.
oxygen and rust are not formed.
If a raindrop falls on a shiny iron surface, it remains transparent in
over a short period of time. Iron and oxygen in water begin to
interact and form an oxide, that is, rust, inside the drop. The water becomes
reddish, and rust floats in the water in the form of small particles. When the drop evaporates, it remains
rust, forming a reddish layer on the surface of the iron.
If rust has already appeared, it will grow in dry air. This happens because
porous rust stain absorbs moisture contained in the air - it attracts and
holds her. This is why it is easier to prevent rust than to stop it once it has appeared.
The problem of rust prevention is very important, since iron and steel products must be stored for a long time. Sometimes they are covered with a layer of paint or plastic. What would you do to
protect warships from rust when not in use? This issue has been resolved with
using moisture absorbers. Such mechanisms replace moist air in compartments with dry air.
Rust in such conditions can not appear! (Encyclopedia).
It is known that every natural phenomenon, including rusting and not rusting, as a result, is based on a cause.
The root cause of fluctuations and natural phenomena, as a single point of view on the Universe, was discovered (including) in such an experiment: light incident on solid crystals is reflected with dispersion. Downgrading
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At the temperature of the crystals, the scattering decreases to a certain limit and, contrary to classical concepts, is retained upon further cooling. As a result, scientists have come to the conclusion that
there are indestructible vibrations of particles (primary motion) with a certain "zero" amplitude A and energy equal to Planck's constant: h=6.626 10-34, J/T,
(see Zero point oscillations, quantum mechanics from Wikipedia, the free encyclopedia).
Actions of indestructible “zero” attractive and repulsive vectors of volumetrically oscillating bodies in a single time,
represent a natural root cause (diffusion, Brownian motion). And the consequence, secondary, are the results of all of them.
interactions that have a (Tao-divine-genetically-thermodynamic) self-organizing building-destructive course: (stretched in time) - from the birth of “something”, growing up, aging and decay on all universal scales.
The half-life of a quantum mechanical system (particle, nucleus, atom ...) is the time T during which the system decays with probability; If an ensemble of independent particles is considered, then during one half-life T, the number of surviving particles will decrease on average by a factor of 2. For example, half-life:
Potassium - 39.1 (19) is T = 1.28 106 years;
uranium - 238 (92) T=4.5 109 years;
thorium - 232 (90) T = 1.41 1010 years. (Encyclopedia).
The planet Earth was supposedly formed from the asteroid belt. Asteroids, consisting of the elements of the periodic table and their combinations, in the form of platforms, shields of various names and sizes, which once constituted a belt rotating between Venus and Mars (while maintaining the momentum), formed, like a fan, into a double of the planet - the Earth and the Moon. Similarly, all the planets of the solar system formed from their asteroid belts. The asteroid belt between Mars and Jupiter is not the decayed planet Phaethon, but the future one. During the transition of the asteroid belt into geo - selenium objects - its various names, platforms, plates, shields, etc., gathering in a heap, were broken and crushed, but voids remained between them. The action of gravity and time displaced voids. And when the period of decay came, the temperature of the Earth began to rise. Ice asteroids (and they could be, including, in the center) - turned into water. Gravity, as the basis of tectonics, forced denser bodies to descend towards the center of the Earth, displacing less dense objects and water, changing the terrain, creating elevation changes. Unsalted water (sources) as atmospheric
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sediments, rivers, seas and oceans eroded asteroids protruding to the surface (including salts), from which sedimentary deposits of minerals were formed, for example: iron, manganese, coal ... and
salinity in the oceans. Whereas non-blurred asteroids began to represent primary deposits of minerals, including oil and gas. (See www.oskar-laar.at.ua pp. 22-23).
And now it remains to compare the ages of the stainless meteorite iron of the Kutub column with iron of terrestrial origin.
Let (conditionally) the unit of time of each period Tt (birth-Tt, growing up-Tt, aging-Tt, decay-Tt) be the half-life
Thorium - 232 (90) Tt = 1.41 1010 years.
Then the terrestrial iron will have an age of four units 4Tt=Tt+Tt+Tt+Tt, and the Kutub iron will be only one unit of Tt. The answer lies on the surface:
Kutub meteoric iron is young, has immunity, and therefore does not rust.
And terrestrial iron - old (decaying, changing properties), has already lost its immunity, therefore it rusts.
As expected, the root cause is one - age, and the consequences are different.
In the same vein: metal fatigue, the apparatus could not withstand the load, a crack appeared, and so on.
Possibly, taster scientists will take into account the "working experience" and age-related loads for iron.
Reviews
"Planet Earth was supposedly formed from the asteroid belt" - "presumably!" that's the whole point of this work...
Anything can be explained (pulled by the ears) ... especially if there is a name in science ... only whether it will be true in the last (or first ...) meaning.
I remember that Kapitsa could not explain why the tea leaves (when stirred) gather in the center of the glass ... or rather, he explained ... complex flows (fell before his eyes).
There are such scientists - Darwins (with a small letter and with complete contempt) ... they know how to assume (laughing) ... the main thing is not to become like that ... it's better to say: "We don't know yet."
And finally tell me:
- What is fire?
Then you can climb into the jungle.
Metal corrosion is a widespread cause that renders various metal parts unusable. Metal corrosion (or rusting) is the destruction of metal under the influence of physical and chemical factors. The factors causing corrosion include natural precipitation, water, temperature, air, various alkalis and acids, etc.
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Metal corrosion is becoming a serious problem in construction, at home and in industry. Most often, designers provide for the protection of metal surfaces from rust, but sometimes rusting occurs on unprotected surfaces and on specially treated parts.
Metal alloys form the basis of human life, they surround him almost everywhere: at home, at work, in the process of recreation. People do not always notice metal things and details, but they constantly accompany them. Various alloys and pure metals are the most produced substances on our planet. Modern industry produces various alloys 20 times more (by weight) than all other materials. Although metals are considered among the most durable substances on Earth, they can break down and lose their characteristics as a result of rusting processes. Under the influence of water, air and other factors, the process of oxidation of metals occurs, which is called corrosion. Despite the fact that not only metal, but also rocks can corrode, the processes associated specifically with metals will be considered below. Here it is worth paying attention to the fact that some alloys or metals are more susceptible to corrosion than others. This is due to the rate of the oxidation process.
Metal oxidation process
The most common substance in alloys is iron. Corrosion of iron is described by the following chemical equation: 3O 2 +2H 2 O+4Fe=2Fe 2 O 3 . H 2 O. The resulting iron oxide is that red rust that spoils objects. But consider the types of corrosion:
- Hydrogen corrosion. It practically does not occur on metal surfaces (although it is theoretically possible). As such, it will not be described.
- oxygen corrosion. Similar to hydrogen.
- Chemical. The reaction occurs due to the action of a metal with some factor (for example, air 3O 2 + 4Fe \u003d 2Fe 2 O 3) and proceeds without the formation of electrochemical processes. So, after exposure to oxygen, an oxide film appears on the surface. On some metals, such a film is strong enough and not only protects the element from destructive processes, but also increases its strength (for example, aluminum or zinc). On some metals, such a film exfoliates (destroys) very quickly, for example, in sodium or potassium. And most metals are destroyed rather slowly (iron, cast iron, etc.). So, for example, corrosion of cast iron occurs. More often, rusting occurs when the alloy comes into contact with sulfur, oxygen, and chlorine. Nozzles, fittings, etc. rust due to chemical corrosion.
- Electrochemical corrosion of iron. This type of rusting occurs in media that conduct electricity (conductors). The time of destruction of various materials during electrochemical reactions is different. Electrochemical reactions are observed in cases of contact between metals that are at a distance in a series of tensions. For example, a product made of steel has copper soldering / fastenings. When water gets on the connections, the copper parts will be cathodes, and the steel will be the anode (each point has its own electrical potential). The rate of such processes depends on the amount and composition of the electrolyte. Reactions require the presence of 2 different metals and an electrically conductive medium. In this case, the destruction of alloys is directly proportional to the current strength. The larger the current, the faster the reaction, the faster the reaction, the faster the destruction. In some cases, alloy impurities serve as cathodes.
Electrochemical corrosion of iron
It is also worth noting the subspecies that occur during rusting (we will not describe, we will only list): underground, atmospheric, gas, with various types of immersion, continuous, contact, caused by friction, etc. All subspecies can be attributed to chemical or electrochemical rusting.
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During construction, corrosion of reinforcement and welded structures is common. Corrosion often occurs due to improper storage of material or failure to perform bar processing. Corrosion of reinforcement is quite dangerous, since reinforcement is laid to reinforce structures, and collapse is possible as a result of the destruction of the rods. Corrosion of welds is no less dangerous than corrosion of reinforcement. This will also significantly weaken the seam and may lead to tearing. There are quite a lot of examples when rust on load-bearing structures leads to the collapse of premises.
Other cases of rusting that are common in everyday life are damage to household tools (knives, cutlery, tools), damage to metal structures, damage to vehicles (both land and air and water), etc.
Perhaps the most common rusty items are keys, knives and tools. All these items are exposed to rust due to the fact that the protective coating is removed by friction, which exposes the base.
The base is subject to destruction processes due to contact with aggressive media (especially knives and tools).
Destruction due to contact with aggressive media
By the way, the destruction of things that are often used in everyday life can be observed almost everywhere and regularly, at the same time, some metal objects or structures can stand rusty for decades and will perform their functions properly. For example, a hacksaw, which was often used to saw logs and left for a month in a shed, quickly rusts and can break during operation, and a pole with a road sign can stand rusty for ten or even more years and not collapse.
Therefore, all metal things should be protected from corrosion. There are several methods of protection, but all this is chemistry. The choice of such protection depends on the type of surface and the destructive factor acting on it.
To do this, the surface is thoroughly cleaned of dirt and dust in order to exclude the possibility of the protective coating not falling on the surface. Then it is degreased (for some types of alloy or metal and for some protective coatings this is necessary), after which a protective layer is applied. Most often, protection is provided by paints and varnishes. Depending on the metal and factors, different varnishes, paints and primers are used.
Another option is to apply a thin protective layer of another material. Usually this method is practiced in production (for example, galvanizing). As a result, the consumer practically does not need to do anything after purchasing the item.
Application of a thin protective layer
Another option is to create special alloys that do not oxidize (for example, stainless steel), but they do not guarantee 100% protection, moreover, some things made from such materials oxidize.
Important parameters of the protective layers are the thickness, service life and rate of destruction under active adverse effects. When applying a protective coating, it is extremely important to fit exactly into the allowable layer thickness. Usually manufacturers of paints and varnishes indicate it on the packaging. So, if the layer is more than the maximum allowable, then this will cause overexpenditure of the varnish (paint), and the layer may collapse under strong mechanical stress, a thinner layer may wear off and reduce the protection period of the base.
Correctly selected protective material and correctly applied to the surface guarantees 80% that the part will not be subject to corrosion.
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Many people in everyday life do not think about how to protect their belongings from rye. And they get a problem in the form of a damaged item. How to solve this problem correctly?
Removing rust from a part
In order to restore a thing or part from rust, the first step is to remove all red plaque to a clean surface. It is removed with sandpaper, files, strong reagents (acids or alkalis), but drinks such as Coca-Cola deserve special fame in this. To do this, the thing is completely immersed in a container with a miracle liquid and left for a while (from several hours to several days - the time depends on the thing and the damaged area).
Red spots on steel products
According to the UN, each country annually loses from 0.5 to 7-8% of the gross national product due to corrosion. The paradox is that the less developed countries lose less than the developed ones. And 30% of all manufactured steel products on the planet are used to replace rusted ones. Therefore, it is highly recommended to take this issue seriously.