The most durable material in the world is carbine. The hardest materials in the world The lightest solid material
Each of you knows that diamond remains the standard of hardness today. When determining the mechanical hardness of materials existing on earth, the hardness of diamond is taken as a standard: when measured by the Mohs method - in the form of a surface sample, by the Vickers or Rockwell methods - as an indenter (as a harder body when examining a body with lower hardness). To date, several materials can be noted, the hardness of which approaches the characteristics of diamond.
In this case, the original materials are compared based on their microhardness according to the Vickers method, when the material is considered superhard at values of more than 40 GPa. The hardness of materials can vary, depending on the characteristics of the synthesis of the sample or the direction of the load applied to it.
Fluctuations in hardness values from 70 to 150 GPa is a generally established concept for hard materials, although 115 GPa is considered to be a reference value. Let's take a look at the 10 hardest materials other than diamond that exist in nature.
10. Boron suboxide (B 6 O) - hardness up to 45 GPa
Boron suboxide has the ability to create grains shaped like icosahedrons. The formed grains in this case are not isolated crystals or varieties of quasicrystals, representing a kind of twin crystals, consisting of two dozen paired crystals-tetrahedra.
10. Rhenium diboride (ReB 2) - hardness 48 GPa
Many researchers question whether this material can be classified as a superhard type of material. This is due to the highly unusual mechanical properties of the compound.
The layer-by-layer alternation of different atoms makes this material anisotropic. Therefore, the measurement of hardness indicators turns out to be different in the presence of different types of crystallographic planes. Thus, testing rhenium diboride at low loads provides a hardness of 48 GPa, and with increasing load, the hardness becomes much less and is approximately 22 GPa.
8. Magnesium aluminum boride (AlMgB 14) - hardness up to 51 GPa
The composition is a mixture of aluminum, magnesium, boron with low sliding friction, as well as high hardness. These qualities could be a godsend for the production of modern machines and mechanisms that work without lubrication. But the use of the material in such a variation is still considered prohibitively expensive.
AlMgB14 - special thin films created by pulsed laser deposition, have the ability to have microhardness up to 51 GPa.
7. Boron-carbon-silicon - hardness up to 70 GPa
The basis of such a connection provides the alloy with qualities that imply optimal resistance to chemical influences of a negative type and high temperature. Such material is provided with microhardness up to 70 GPa.
6. Boron carbide B 4 C (B 12 C 3) - hardness up to 72 GPa
Another material is boron carbide. The substance began to be used quite actively in various fields of industry almost immediately after its invention in the 18th century.
The microhardness of the material reaches 49 GPa, but it has been proven that this indicator can also be increased by adding argon ions to the structure of the crystal lattice - up to 72 GPa.
5. Carbon-boron nitride - hardness up to 76 GPa
Researchers and scientists from all over the world have long been trying to synthesize complex superhard materials, in which tangible results have already been achieved. The components of the compound are boron, carbon and nitrogen atoms - similar in size. The qualitative hardness of the material reaches 76 GPa.
4. Nanostructured cubonite - hardness up to 108 GPa
The material is also called kingsongite, borazone or elbor, and also has unique qualities that are successfully used in modern industry. With cubonite hardness values of 80-90 GPa, close to the diamond standard, the strength of the Hall-Petch law can cause their significant growth.
This means that with a decrease in the size of crystalline grains, the hardness of the material increases - there are certain possibilities for increasing up to 108 GPa.
3. Wurtzite boron nitride - hardness up to 114 GPa
The wurtzite crystal structure provides high hardness to this material. With local structural modifications, during the application of a specific type of load, the bonds between atoms in the lattice of a substance are redistributed. At this point, the quality hardness of the material becomes 78% higher.
Lonsdaleite is an allotropic modification of carbon and is distinctly similar to diamond. A solid natural material was discovered in a meteorite crater, formed from graphite, one of the meteorite components, but it did not have a record degree of strength.
Scientists have proven back in 2009 that the absence of impurities can provide a hardness exceeding the hardness of diamond. High hardness values can be achieved in this case, as in the case of wurtzite boron nitride.
Polymerized fullerite is now considered the hardest material known to science. This is a structured molecular crystal, the nodes of which are composed of whole molecules, and not of individual atoms.
Fullerite has a hardness of up to 310 GPa and is capable of scratching a diamond surface like normal plastic. As you can see, diamond is no longer the hardest natural material in the world, harder compounds are available to science.
So far, these are the hardest materials on Earth known to science. It is quite possible that soon we will have new discoveries and a breakthrough in the field of chemistry / physics, which will allow us to achieve higher hardness.
In his activity, a person uses various qualities of substances and materials. And not unimportant is their strength and reliability. The hardest materials in nature and artificially created will be discussed in this article.
Commonly accepted standard
To determine the strength of the material, the Mohs scale is used - a scale for assessing the hardness of a material by its reaction to scratching. For the layman, the hardest material is diamond. You will be surprised, but this mineral is only somewhere in the 10th place among the hardest. On average, a material is considered superhard if its values are above 40 GPa. In addition, when identifying the hardest material in the world, the nature of its origin should also be taken into account. At the same time, strength and strength often depend on the influence of external factors on it.
The hardest material on earth
In this section, we will pay attention to chemical compounds with an unusual crystal structure, which are much stronger than diamonds and may well scratch it. Here are the top 6 hardest materials created by man, starting with the least hard.
- Carbon nitride - boron. This achievement of modern chemistry has a strength index of 76 GPa.
- Graphene airgel (aerographene) - a material 7 times lighter than air, restoring its shape after 90% compression. An amazingly durable material that can also absorb 900 times its own weight in liquid or even oil. This material is planned to be used in case of oil spills.
- Graphene is a unique invention and the most durable material in the universe. A little more about him below.
- Carbin is a linear polymer of allotropic carbon, from which super-thin (1 atom) and super-strong tubes are made. For a long time, no one was able to build such a tube with a length of more than 100 atoms. But Austrian scientists from the University of Vienna managed to overcome this barrier. In addition, if earlier carbine was synthesized in small quantities and was very expensive, today it is possible to synthesize it in tons. This opens up new horizons for space technology and beyond.
- Elbor (kingsongite, cubonite, borazone) is a nanodesigned compound that is widely used today in metal processing. Hardness - 108 GPa.
- Fullerite is the hardest material on Earth known to man today. Its strength of 310 GPa is ensured by the fact that it does not consist of individual atoms, but of molecules. These crystals will easily scratch a diamond like a knife through butter.
The miracle of human hands
Graphene is another invention of mankind based on allotropic modifications of carbon. In appearance - a thin film one atom thick, but 200 times stronger than steel, with exceptional flexibility.
It is about graphene that they say that in order to pierce it, an elephant must stand on the tip of a pencil. At the same time, its electrical conductivity is 100 times higher than the silicon of computer chips. Very soon it will leave laboratories and enter everyday life in the form of solar panels, cell phones and modern computer chips.
Two very rare results of anomalies in nature
In nature, there are very rare compounds that have incredible strength.
- Boron nitride is a substance whose crystals have a specific wurtzite shape. With the application of loads, the connections between the atoms in the crystal lattice are redistributed, increasing the strength by 75%. The hardness index is 114 GPa. This substance is formed during volcanic eruptions, in nature it is very small.
- Lonsdaleite (in the main photo) is an allotropic carbon compound. The material was found in a meteorite crater and is thought to have formed from graphite under the conditions of the explosion. The hardness index is 152 GPa. Rarely found in nature.
Wonders of wildlife
Among the living beings on our planet, there are those who have something very special.
- Web of Caaerostris darwini. The thread that Darwin's spider emits is stronger than steel and harder than Kevlar. It was this web that was adopted by NASA scientists in the development of space protective suits.
- Mollusk teeth Sea saucer - their fibrous structure is currently being studied by bionics. They are so strong that they allow the mollusk to tear off the algae that have grown into the stone.
iron birch
Another miracle of nature is the Schmidt birch. Its wood is the hardest of biological origin. It grows in the Far East in the Kedrovaya Pad Nature Reserve and is listed in the Red Book. Strength is comparable to iron and cast iron. But at the same time it is not subject to corrosion and rotting.
The widespread use of wood, which even bullets cannot penetrate, is hindered by its exceptional rarity.
The hardest of metals
It is a white-blue metal - chrome. But its strength depends on its purity. In nature, it contains 0.02%, which is not at all so small. It is extracted from silicate rocks. A lot of chromium is also contained in meteorites falling to Earth.
It is corrosion resistant, heat resistant and refractory. Chromium is a component of many alloys (chromium steel, nichrome), which are widely used in industry and in anti-corrosion decorative coatings.
Stronger Together
One metal is good, but in some combinations it is possible to give the alloy amazing properties.
An ultra-strong alloy of titanium and gold is the only strong material that has proven to be biocompatible with living tissues. The alloy beta-Ti3Au is so strong that it cannot be ground in a mortar. It is already clear today that this is the future of various implants, artificial joints and bones. In addition, it can be applied in drilling, sports equipment and many other areas of our lives.
An alloy of palladium, silver, and some metalloids may also have similar properties. Scientists from the Caltech Institute are currently working on this project.
The future at $20 a skein
What is the hardest material that any average person can buy today? For just $20, you can buy 6 meters of Braeön tape. Since 2017, it has been on sale from the manufacturer Dustin McWilliams. The chemical composition and method of production are kept in strict confidence, but its qualities are amazing.
Tape can hold everything together. To do this, it must be wrapped around the parts to be fastened, heated with an ordinary lighter, the plastic composition must be given the desired shape and that's it. After cooling, the joint will withstand a load of 1 ton.
Both hard and soft
In 2017, information appeared about the creation of an amazing material - the hardest and softest at the same time. This metamaterial was invented by scientists from the University of Michigan. They managed to learn how to control the structure of the material and make it exhibit various properties.
For example, when using it to create cars, the body will be rigid when moving, and soft when colliding. The body absorbs contact energy and protects the passenger.
The world around us is still fraught with many mysteries, but even phenomena and substances known to scientists for a long time do not cease to amaze and delight. We admire bright colors, enjoy tastes and use the properties of all kinds of substances that make our life more comfortable, safer and more enjoyable. In search of the most reliable and strong materials, man has made many exciting discoveries, and in front of you is a selection of just 25 such unique compounds!
25. Diamonds
If not everyone, then almost everyone knows this for sure. Diamonds are not only one of the most revered gemstones, but also one of the hardest minerals on Earth. On the Mohs scale (a scale of hardness in which an assessment is given by the reaction of a mineral to scratching), diamond is listed on the 10th line. There are 10 positions in the scale, and the 10th is the last and hardest degree. Diamonds are so hard that they can only be scratched with other diamonds.
24. Trapping webs of the spider species Caaerostris darwini
Photo: pixabay
It's hard to believe, but the network of the spider Caerostris darwini (or Darwin's spider) is stronger than steel and harder than Kevlar. This web was recognized as the hardest biological material in the world, although now it has a potential competitor, but the data has not yet been confirmed. Spider fiber was tested for characteristics such as breaking strain, impact strength, tensile strength and Young's modulus (the property of a material to resist stretching, compression under elastic deformation), and in all these indicators, the web showed itself in an amazing way. In addition, the trapping web of the Darwin spider is incredibly light. For example, if we wrap our planet with Caaerostris darwini fiber, the weight of such a long thread will be only 500 grams. Such long networks do not exist, but the theoretical calculations are simply amazing!
23. Aerographite
Photo: BrokenSphere
This synthetic foam is one of the lightest fibrous materials in the world and is a network of carbon tubes only a few microns in diameter. Aerographite is 75 times lighter than polystyrene, but at the same time much stronger and more ductile. It can be compressed down to 30 times its original size without any harm to its extremely elastic structure. Thanks to this property, airgraphite foam can withstand loads up to 40,000 times its own weight.
22. Palladium metallic glass
Photo: pixabay
A team of scientists from the California Institute of Technology and Berkeley Lab (California Institute of Technology, Berkeley Lab) has developed a new type of metallic glass that combines a near-perfect combination of strength and ductility. The reason for the uniqueness of the new material lies in the fact that its chemical structure successfully masks the brittleness of existing glassy materials while maintaining a high endurance threshold, which ultimately significantly increases the fatigue strength of this synthetic structure.
21. Tungsten carbide
Photo: pixabay
Tungsten carbide is an incredibly hard material with high wear resistance. Under certain conditions, this compound is considered very brittle, but under heavy load it shows unique plastic properties, manifesting itself in the form of slip bands. Thanks to all these qualities, tungsten carbide is used in the manufacture of armor-piercing tips and various equipment, including all kinds of cutters, abrasive discs, drills, cutters, drill bits and other cutting tools.
20. Silicon carbide
Photo: Tiia Monto
Silicon carbide is one of the main materials used to make battle tanks. This compound is known for its low cost, outstanding refractoriness and high hardness, and is therefore often used in the manufacture of equipment or gear that must deflect bullets, cut or grind other hard materials. Silicon carbide makes excellent abrasives, semiconductors, and even inlays in jewelry that mimic diamonds.
19. Cubic boron nitride
Photo: wikimedia commons
Cubic boron nitride is a superhard material, similar in hardness to diamond, but also has a number of distinctive advantages - high temperature stability and chemical resistance. Cubic boron nitride does not dissolve in iron and nickel even under the influence of high temperatures, while diamond under the same conditions enters into chemical reactions rather quickly. In fact, this is beneficial for its use in industrial grinding tools.
18. Ultra High Molecular Weight Polyethylene (UHMWPE), Dyneema fiber brand
Photo: Justsail
High modulus polyethylene has extremely high wear resistance, low coefficient of friction and high fracture toughness (low temperature reliability). Today it is considered the strongest fibrous substance in the world. The most amazing thing about this polyethylene is that it is lighter than water and can stop bullets at the same time! Cables and ropes made of Dyneema fibers do not sink in water, do not need lubrication and do not change their properties when wet, which is very important for shipbuilding.
17. Titanium alloys
Photo: Alchemist-hp (pse-mendelejew.de)
Titanium alloys are incredibly ductile and show amazing strength when stretched. In addition, they have high heat resistance and corrosion resistance, which makes them extremely useful in areas such as aircraft, rocketry, shipbuilding, chemical, food and transportation engineering.
16. Liquid metal alloy
Photo: pixabay
Developed in 2003 at the California Institute of Technology, this material is renowned for its strength and durability. The name of the compound is associated with something brittle and liquid, but at room temperature it is actually unusually hard, wear-resistant, not afraid of corrosion and transforms when heated, like thermoplastics. The main areas of application so far are the manufacture of watches, golf clubs and covers for mobile phones (Vertu, iPhone).
15. Nanocellulose
Photo: pixabay
Nanocellulose is isolated from wood fibers and is a new type of wood material that is even stronger than steel! In addition, nanocellulose is also cheaper. The innovation has great potential and could seriously compete with glass and carbon fiber in the future. The developers believe that this material will soon be in great demand in the production of army armor, super-flexible screens, filters, flexible batteries, absorbent aerogels and biofuels.
14. Teeth of snails of the "sea saucer" type
Photo: pixabay
Earlier, we already told you about the trapping web of Darwin's spider, which was once recognized as the most durable biological material on the planet. However, a recent study showed that the limpet is the most durable biological substance known to science. Yes, these teeth are stronger than the web of Caaerostris darwini. And this is not surprising, because tiny sea creatures feed on algae growing on the surface of harsh rocks, and these animals have to work hard to separate food from the rock. Scientists believe that in the future we will be able to use the example of the fibrous structure of the teeth of limpets in the engineering industry and begin to build cars, boats and even aircraft of increased strength, inspired by the example of simple snails.
13. Maraging steel
Photo: pixabay
Maraging steel is a high strength and high alloy alloy with excellent ductility and toughness. The material is widely used in rocket science and is used to make all kinds of tools.
12. Osmium
Photo: Periodictableru / www.periodictable.ru
Osmium is an incredibly dense element, and due to its hardness and high melting point, it is difficult to machine. That is why osmium is used where durability and strength are most valued. Osmium alloys are found in electrical contacts, rocketry, military projectiles, surgical implants, and many other applications.
11. Kevlar
Photo: wikimedia commons
Kevlar is a high-strength fiber found in car tires, brake pads, cables, prosthetics, body armor, protective clothing fabrics, shipbuilding, and drone parts. The material has become almost synonymous with strength and is a type of plastic with incredibly high strength and elasticity. The tensile strength of Kevlar is 8 times higher than that of steel wire, and it begins to melt at a temperature of 450℃.
10. Ultra high molecular weight polyethylene of high density, brand of fibers "Spectra" (Spectra)
Photo: Tomas Castelazo, www.tomascastelazo.com / Wikimedia Commons
UHMWPE is essentially a very durable plastic. Spectra, the UHMWPE brand, is, in turn, a light fiber of the highest wear resistance, 10 times superior to steel in this indicator. Like Kevlar, spectrum is used in the manufacture of body armor and protective helmets. Along with UHMWPE, dainimo spectrum is popular in the shipbuilding and transport industries.
9. Graphene
Photo: pixabay
Graphene is an allotropic modification of carbon, and its crystal lattice, just one atom thick, is so strong that it is 200 times harder than steel. Graphene looks like cling film, but breaking it is an almost impossible task. To punch through a graphene sheet, you have to stick a pencil into it, on which you will have to balance a load with the weight of an entire school bus. Good luck!
8. Carbon nanotube paper
Photo: pixabay
Thanks to nanotechnology, scientists have managed to make paper that is 50,000 times thinner than a human hair. Sheets of carbon nanotubes are 10 times lighter than steel, but the most amazing thing is that they are as much as 500 times stronger! Macroscopic nanotube plates are the most promising for the manufacture of supercapacitor electrodes.
7. Metal microgrid
Photo: pixabay
Here is the lightest metal in the world! The metal microgrid is a synthetic porous material that is 100 times lighter than foam. But don't let its appearance fool you, these microgrids are also incredibly strong, making them great potential for use in all sorts of engineering applications. They can be used to make excellent shock absorbers and thermal insulators, and the amazing ability of this metal to shrink and return to its original state allows it to be used to store energy. Metal microgrids are also actively used in the production of various parts for the aircraft of the American company Boeing.
6. Carbon nanotubes
Photo: User Mstroeck / en.wikipedia
Above, we have already talked about ultra-strong macroscopic carbon nanotube plates. But what kind of material is this? In fact, these are graphene planes rolled into a tube (9th point). The result is an incredibly light, resilient and durable material for a wide range of applications.
5. Airbrush
Photo: wikimedia commons
Also known as graphene airgel, this material is extremely light and strong at the same time. The new type of gel has completely replaced the liquid phase with a gaseous one, and it is characterized by sensational hardness, heat resistance, low density and low thermal conductivity. Incredibly, graphene airgel is 7 times lighter than air! The unique compound is able to regain its original shape even after 90% compression and can absorb up to 900 times the weight of oil used to absorb airbrush. Perhaps in the future this class of materials will help in the fight against environmental disasters such as oil spills.
4. Material without a name, the development of the Massachusetts Institute of Technology (MIT)
Photo: pixabay
As you read this, a team of scientists at MIT is working to improve the properties of graphene. The researchers said that they have already managed to convert the two-dimensional structure of this material into three-dimensional. The new graphene substance has not yet received its name, but it is already known that its density is 20 times less than that of steel, and its strength is 10 times higher than that of steel.
3. Carbin
Photo: Smokefoot
Even though it's just linear chains of carbon atoms, carbyne has 2x the tensile strength of graphene and is 3x harder than diamond!
2. Boron nitride wurtzite modification
Photo: pixabay
This newly discovered natural substance is formed during volcanic eruptions and is 18% harder than diamonds. However, it surpasses diamonds in a number of other parameters. Wurtzite boron nitride is one of only 2 natural substances found on Earth that is harder than diamond. The problem is that there are very few such nitrides in nature, and therefore they are not easy to study or apply in practice.
1. Lonsdaleite
Photo: pixabay
Also known as hexagonal diamond, lonsdaleite is made up of carbon atoms, but in this modification, the atoms are arranged slightly differently. Like wurtzite boron nitride, lonsdaleite is a natural substance that is harder than diamond. Moreover, this amazing mineral is harder than diamond by as much as 58%! Like wurtzite boron nitride, this compound is extremely rare. Sometimes lonsdaleite is formed during a collision with the Earth of meteorites, which include graphite.
Many of us are well aware of the basic properties of, for example, ordinary plywood - its strength, rigidity, stability and dimensions.
But, most likely, you are not familiar with the properties of other sheet materials that have appeared in recent years.
No matter what project you have to produce, we will help you find the material that is ideally suited to your tasks.
Improved properties thanks to modern developments
All sheet and board materials, including plywood, belong to the broad category of man-made wood products. Unlike natural, natural wood, when boards and beams are simply sawn out of a tree trunk and dried, artificial materials are obtained through further processing, seeking to improve or change some properties.
For example, plywood consists of many thin layers glued to each other so that the direction of the fibers of each layer is perpendicular to the adjacent ones. This increases strength, reduces dimensional fluctuations, and allows beautifully textured woods to be used only on the outer layers.
Although plywood still dominates the market, there are a growing number of new sheet materials made from shavings, sawdust or powdered wood that are mixed with glue and special additives and then pressed. This is how widely known chipboards and fibreboards (chipboard and MDF) are produced. Even traditional plywood has changed by partially replacing the inner or outer layers with other materials, and becoming popular high density plywood is glued from many very thin layers of veneer.
The article describes the purpose and properties of a dozen sheet and plate materials. Note.
We have omitted some materials, such as OSI (oriented strand board) and antiseptic plywood, which are intended for construction and not for carpentry work.
Description of sheet materials
- 1. Material
- 2. Description
- 3. Application
- 4. Standard sizes
- 5. Varieties
- 6. Benefits
- 7. Disadvantages
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1. chipboard
2. Consists of sawdust and wood flour with special additives. Thermal pressing into sheets and plates.
3. Widely used as a flooring underlay, for making cheap cabinet furniture. Limited use in workshops for the manufacture of some devices.
4. Sheets and plates with a thickness of 6; 12; sixteen; nineteen; 25 and 32 NI.
5. PBU - for the subfloor M-S, M-1, M-2 and M-3 - for the manufacture of cabinet furniture and countertops.
6. Low cost and availability, ease of processing and relative dimensional stability.
7. Insufficient rigidity, low moisture resistance. The fastener does not hold well.
1. Chipboard with melamine coating (LDSP)
2. One or both surfaces of chipboard are lined with paper impregnated with melamine resins. On cheap varieties, plastic is simply glued, and on expensive ones it is firmly bonded to the base by heating.
3. Great for making cabinet furniture as the plastic surface is easy to clean. Use to make fixtures and simple router tables.
4. Sheets and plates with a size of 1250×2500 mm and a thickness of 5; 12; 16 and 18 mm.
5. There are no standard gradations of chipboard, but there are so-called "vertical" and "horizontal" varieties. Expensive varieties usually have a thicker and more durable coating film.
6. Inexpensive available material with an easy to clean surface. Wide range of colors. There are varieties coated with kraft paper or natural veneer.
7. Heavy material with low moisture resistance. The cut edges are often damaged by chips when cutting with saw blades not designed for this material.
1. Hardboard
2. A mixture of ground wood fibers with resins, pressed into sheets. One or both sides of the sheet may be smooth.
3. Great for making DIY fixtures and workshop furniture, especially the two smooth side variety. Perforated hardboard is a convenient means for hanging tools.
4. Sheets with a thickness of 3 and b mm.
5. Rough (2 green stripes), standard (1 green stripe), medium hard (2 red stripes), hard (1 red stripe), S1S (one smooth side), S2S (both smooth sides).
6. Available and inexpensive material, easy to process, relatively stable, good coloring.
7. Standard and draft grades are not moisture resistant, poorly sanded and do not hold fasteners well. Their edges are easily damaged.
1. Medium Density Fibreboard (MDF)
2. A mixture of cellulose fibers with synthetic resins, compressed by heating.
3. Great for making fixtures, cabinet furniture, painted products, trim profiles. It is used as a base for sticking veneer and plastics.
5. Main variety: Industrial. Cheap varieties are designated by the brand "B" or "shop". Also classified by density: standard - MD, low density - LD.
6. Smooth surfaces, no internal and external defects, stable thickness. Sticks well. Edges are easy to process.
7. Heavy material. Ordinary screws do not hold well.
1. Coniferous plywood
2. Cross-glued layers of softwood veneer.
3. Garden furniture, outdoor buildings and structures, workshop furniture, flooring base.
4. Sheets and plates with a thickness of 6; ten; 12; sixteen; 19 and 22 mm sizes 1220×2440 and 1225×2500 mm.
5. Grades A, B, C, D (I, II, III, IV).
6. Cheaper hardwood plywood. On premium plywood, the face veneer often has a beautiful texture pattern.
7. Beautiful appearance often hides many defects. Low hardness.
1. Laminated plywood
2. Plywood with a double-sided coating of thick paper impregnated with synthetic resins.
4. Sheets and plates with a thickness of 6; eight; ten; 12; 16 and 19 mm with dimensions of 1220 × 2440 mm.
5. Classified by grade in the same way as hardwood plywood. The outer layers (glued over with paper) are made of grade B (II) or A (I) veneer, the inner layers are made of grade C (III) veneer.
6. Smooth surfaces paint well. Easily processed. Durable weather resistant material.
7. Heavy material. Limited availability.
1. Decorative plywood
2. Plywood with outer layers of fine wood veneer.
3. It is used for the manufacture of furniture and interior decoration.
4. Sheets with a thickness of 3; 6; ten; 12; 16 and 19 mm.
5. Veneer grades on the front side: AA, A, B, C/D/E on the back side: 1,2,3,4.
6. More stable and cheaper than solid wood. No external defects on the front side. Beautiful appearance.
7. Thick sheets can be heavy. Thin veneer is easily damaged. The edges of the parts have to be covered with overlays.
1. birch plywood
2. Glued together from thin layers of veneer. In expensive varieties, there are no internal defects.
3. Applied to making fixtures, furniture, drawers.
4. Sheets with a size of 1525×1525 mm and a thickness of 4; 6; 5; nine; 12; 15 and 18 mm.
5. Grades: AA, A, B, C, D.
6. Rigidity, stability, no defects. Holds screws well. Finished edges are decorative.
7. Heavy material. The outer layers are birch veneer only.
1. Plywood «Appleply»
2. American variety of high quality birch plywood with fine wood veneer outer layers.
3. Used in the same way as European birch plywood, mainly for decorative purposes.
4. Sheets and plates with a thickness of 6; ten; thirteen; nineteen; 25 and 32 mm with dimensions of 1220 × 2440 mm.
5. There is no gradation by grade, but grade "B" or "A" veneer is used for the outer layers.
6. Rigidity, stability, no defects. Holds fasteners well. Variety of veneer on front sides.
7. Limited availability, high cost.
1. flexible plywood
2. All inner layers of the veneer are perpendicular to the outer ones, which allows the plywood to be bent across the fibers of the outer layer.
3. The main use is as a base in the manufacture of furniture.
4. Sheets 3 and 10 mm thick, 1220×2440 mm in size. Sheets of other thicknesses are produced on request.
5. Bends along small radii without cracking, does not require steaming or cross cuts.
6. With increased flexibility, it allows you to make rounded corners and decorative shapes.
7. Not applicable for loaded structures. The quality of the veneer on the front sides is not standardized.
1. Always carefully measure the thickness of sheet materials before selecting grooves or tongues in adjacent parts. For example, the thickness of plywood is often 0.3-0.8 mm less than the nominal.
2. When sawing sheet materials on the saw, place them face up to avoid chipping. When cutting with a circular saw, they should be placed face down.
If you follow the latest in the world of modern technology, then this material will not be big news for you. However, it is useful to take a closer look at the lightest material in the world and learn a little more detail.
Less than a year ago, the title of the lightest material in the world was given to a material called airbrush. But this material did not manage to hold the palm for a long time, it was intercepted not so long ago by another carbon material called graphene airgel. Created by a research group in the laboratory of the Division of Polymer Science and Technology at Zhejiang University, led by Professor Gao Chao, the ultralight graphene airgel has a density slightly lower than that of helium gas and slightly higher than that of hydrogen gas.
Aerogels, as a class of materials, were developed and produced in 1931 by engineer and chemist Samuel Stephens Kistler. Since then, scientists from various organizations have been researching and developing such materials, despite their dubious value for practical use. An airgel composed of multilayer carbon nanotubes, dubbed "frozen smoke" and having a density of 4 mg/cm3, lost the title of the lightest material in 2011, which passed to a metal microlattice material with a density of 0.9 mg/cm3. And a year later, the title of the lightest material passed to a carbon material called aerographite, whose density is 0.18 mg / cm3.
The new holder of the title of the lightest material, graphene airgel, created by the team of Professor Chao, has a density of 0.16 mg/cm3. In order to create such a lightweight material, scientists used one of the most amazing and thin materials to date - graphene. Using their experience in creating microscopic materials, such as "one-dimensional" graphene fibers and two-dimensional graphene ribbons, the team decided to add another dimension to the two dimensions of graphene and create a bulk porous graphene material.
Instead of the molding method, which uses a solvent material and which is usually used to produce various aerogels, Chinese scientists have used the freeze-drying method. Sublimation drying of a cooloid solution consisting of a liquid filler and graphene particles made it possible to create a porous carbon sponge, the shape of which almost completely repeated the given shape.
“There is no need to use templates, the size and shape of the carbon ultralight material we create depends only on the shape and dimensions of the container,” says Professor Chao, “The amount of airgel produced depends only on the size of the container, which can have a volume measured in thousands of cubic centimeters.”
The resulting graphene airgel is an extremely strong and resilient material. It can absorb organic materials, including oil, weighing up to 900 times its own weight with a high absorption rate. One gram of airgel absorbs 68.8 grams of oil in just one second, making it an attractive material to use as an absorber for oil spilled in the ocean.
In addition to serving as an oil scavenger, graphene airgel has the potential to be used in energy storage systems, as a catalyst for some chemical reactions, and as a filler for complex composite materials.