Detailed information of traditional materials

Traditional materials, the so-called materials, refers to human beings used to make useful objects of matter; materials are the material basis of human survival and development, is an important pillar of human society and civilization.

New materials are materials that have recently been developed or are being developed with more excellent properties than traditional materials.

Each major breakthrough in materials science and technology will cause a revolution in production technology and greatly accelerate the process of social development.

Historical staging: the materials of human tools

Stone Age, Pottery Age, Bronze Age, Iron Age, Silicon Age.

Basic introduction Chinese name: traditional material Foreign name: traditional material Material properties: ductility, stability, plasticity Material classification: physical properties and uses Material properties, ductility, stability, plasticity, material classification, metallic materials, non-metallic materials, material properties ductility that is, the ductility and spreading. Ductility is the property of being able to extend, for example, iron can be made into wire; spreadability is the property of being able to unfold, for example, aluminum can be made into very thin aluminum foil. Generally speaking, the ductility of the material is excellent, so can be collectively referred to as ductility. Stability is a chemical property, such as whether it decomposes easily when exposed to light or heat, or whether it reacts easily with oxygen. Plasticity means that when a material is subjected to an external force at a certain temperature and pressure, it can be deformed and remain in the same state as when the force was applied after the force is removed. Classification of materials Metallic materials include pure metals and alloys, and alloys are mixtures. Such as copper, aluminum, steel Inorganic non-metallic materials: such as cement, ceramics, glass Organic synthetic materials: such as plastic, rubber, synthetic fibers The composition of the alloy by the combination of two or more metals, generally it will have the function of the advantages of the metal components, and even some new functions. Iron and steel Ironmaking: Iron ore is mixed with limestone and coke and heated in air to obtain pig iron. Steelmaking: Pig iron is heated in oxygen-enriched air to reduce the carbon content and produce steel. Pig iron is generally hard and brittle, industrially suitable for casting, not forging. Steel generally has a certain degree of toughness, suitable for both casting and forging. So steel is more widely used rust of iron and steel: essentially iron in the presence of water, the process of slow oxidation Due to the rust loose, permeability, water absorption is better, so once the rust of steel products, such as timely treatment, the rust process will not automatically stop, will only get faster and faster. Pollution of metals: Firstly, the pollution caused by the waste gas and slag when smelting metals. One is the pollution caused by the waste metal to the environment. Classification of steel: Comparison of pig iron and steel, iron making and steel making. Copper copper physical properties : pure copper is purple-red, melting point of about 1083.4 ℃, boiling point of 2567 ℃, density 8.92g/cm3, has a good ductility. 1g of pure copper can be pulled into a 3000m fine copper wire or calendered into an area of 10m2 almost transparent copper foil. The conductivity of pure copper is second only to silver, but much cheaper than silver, so today more than half of the world's copper used in power and telecommunications industry. Copper in the humid air is easy to generate copper carbonate alkali on its surface (copper green). Copper is commonly used in the manufacture of copper wire, electrodes and in the electroplating industry. Copper alloys. Aluminum Physical Properties of Aluminum : Pure aluminum is a silvery-white lustrous metal with good ductility, and is used to make aluminum foil for wrapping paper cigarettes and candies. Aluminum's conductivity is second only to silver and copper (conductivity of copper 64%, density less than 2.70g/cm3, 30% of copper), so aluminum is widely used in place of copper for cables. Aluminum has good thermal conductivity, a large number of cookware used in the production, but also can do solar energy absorption device Aluminum is the human following copper, iron, after the third was widely used metal. Aluminum's chemical nature is very active, in the air quickly generate a layer of dense oxide film, can prevent further oxidation, this oxide film is insoluble in water, so that the aluminum does not play with water Aluminum in the oxygen heated when burning violently, emitting dazzling white light, and release a lot of heat. Aluminum has a strong ability to combine with oxygen and is an oxygen-loving element. It can capture oxygen from many metal oxides and generates a great deal of heat, which is so high that it melts the free metal. This can be used to produce metals, often called aluminum heat method, metallurgical industry with aluminum heat method to prepare metal chromium, manganese, vanadium and so on. Example: Cr2O3 + 2Al = Al2O3 + 2Cr Aluminum is an amphoteric metal that reacts with dilute acids (hydrochloric or sulfuric) and strong bases to form salts and emit hydrogen gas. Aluminum is "passivated" when placed in cold nitric acid and does not react with dilute acids. The most important use of aluminum is the manufacture of a variety of lightweight alloys, aluminum alloys have the advantages of light weight and hardness, widely used in aviation, automotive industry and the defense industry, and at the same time in the daily life of the set of more and more widely used, such as the manufacture of windows and doors, furniture and drinking utensils. Pure aluminum is also used in large quantities to make wires and cables, but also used in the manufacture of special paints, ointments, cosmetic tubes and containers and packaging foil. Organic aluminum compounds such as triethylaluminum are used as catalysts for stereospecific polymerization. Aluminum uses (1) aluminum density is very small, only 2.7g/cm3, although it is relatively soft, but can be made into a variety of aluminum alloys, such as duraluminum, super duraluminum; rust-proof aluminum, aluminum casting, etc. These aluminum alloys are widely used in aircraft. These aluminum alloys are widely used in aircraft, automobiles, trains, ships and other manufacturing industries. In addition, space rockets, space shuttles, artificial satellites also use a lot of aluminum and its alloys. For example, a supersonic aircraft consists of about 70% aluminum and its alloys. Ship construction is also a large number of aluminum, a large passenger ship with the amount of aluminum often up to several thousand tons. (2) aluminum conductivity is second only to silver, copper, although its conductivity is only 2/3 of copper, but the density of only 1/3 of copper, so transport the same amount of electricity, the quality of aluminum wire is only half of the copper wire. Aluminum surface oxide film not only has the ability to resist corrosion, but also has a certain degree of insulation, so aluminum in the electrical manufacturing industry, wire and cable industry and the radio industry has a wide range of uses. (3) Aluminum is a good conductor of heat, its thermal conductivity than iron 3 times greater than the industry can use aluminum to manufacture a variety of heat exchangers, heat dissipation materials and cookware. (4) Aluminum's surface is not easily corroded due to the dense oxide protective film, often used to manufacture chemical reactors, medical equipment, refrigeration equipment, oil and gas pipelines, and so on. (5) Aluminum powder has a silver-white luster (general metal in powder form when the color is mostly black), often used to do paint, commonly known as silver powder, silver paint, to protect iron products from corrosion, but also beautiful. (6) aluminum combustion in oxygen can release a lot of heat and dazzling light, commonly used in the manufacture of explosive mixtures, such as ammonium-aluminum explosives (from ammonium nitrate, charcoal powder, aluminum powder, smoke black and other combustible organic matter mixed), combustion mixtures (such as aluminum thermite bombs and shells can be used to attack difficult to fire targets or tanks, artillery, etc.) and lighting mixtures (such as barium nitrate 68%, 28% aluminum powder, 4%). (7) aluminum thermite is often used to melt refractory metals and welding rails. Aluminum is also used as a deoxidizer in the steelmaking process. Aluminum powder and graphite, titanium dioxide (or other high melting point metal oxides) according to a certain ratio of uniform mixing, coated in metal, calcined at high temperatures and made of high-temperature-resistant metal ceramics, it has an important application in rocket and missile technology. (9) Aluminum reflective properties of light is also very good, the purer the aluminum, the better its reflective ability, so it is often used to manufacture high-quality mirrors, such as solar cooker mirrors. (10) Aluminum has sound-absorbing properties, acoustics are also better, so the broadcasting room, modern large-scale building indoor ceiling, etc. are also commonly used aluminum. Aluminum's biological function: Aluminum is not only one of the essential trace elements, but also can be used in medicine to cure diseases. For example, Al(OH)3 has been used for many years to treat gastric and duodenal ulcers. Aluminum is also used to treat gastric and duodenal ulcers for many years. Trace amounts of aluminum in the human body can block the absorption of phosphorus in the intestinal tract, reduce blood phosphorus, prevent secondary hyperparathyroidism caused by increased blood phosphorus, calcification of soft tissues and kidney stone formation, but excessive intake of aluminum into the body will also bring harm. Due to the widespread use of aluminum products and compounds, the amount of aluminum in the body of modern people has increased twofold compared to that of ancient people. When aluminum products contain salty, acidic or alkaline foods, the protective film on their surface is damaged and the aluminum oxide is dissolved into a colloidal solution. When this aluminum oxide is incorporated into food, it increases the intake of aluminum into the body. As a result, the accumulation of aluminum in the body will affect the health of the body. When the accumulation of aluminum in the body exceeds five times the normal value, it can destroy the activity of certain enzymes, reduce gastric acid and cause digestive disorders. Aluminum can also inhibit the absorption of phosphorus in the digestive tract, interfering with phosphorus metabolism, destroying the normal ratio of calcium and phosphorus, affecting the development of bones and teeth, and can make the bones decalcified, softened and loose. In the normal human brain, the aluminum content of only 2 mg ~ 3mg. Due to excessive intake of aluminum, over time will also accumulate in the brain, especially easy to accumulate in the cerebral cortex and the hippocampal region of the brain and other parts of the random movement, so that people's memory loss, emotional indifference, slow reaction, irritability, depression, so that people's brain tissue to accelerate the rate of aging, this phenomenon is known as Alzheimer's disease. In addition, long-term intake of aluminum too much, but also make people's skin wrinkles, hair loss, vision loss. Another major disadvantage of using aluminum cookware is that it cuts off an important channel for people to take in iron, making people suffering from iron-deficiency anemia increase day by day, especially women and children are more obvious. In order to reduce the excessive intake of aluminum cookware in the human body, in the use of aluminum cookware, we should pay attention to the following points: 1. should avoid friction with other hard appliances, in order to prevent the destruction of the aluminum surface oxide film; 2. aluminum products should not be long put salt, sauce, vinegar, wine, tea, fruit juice, baking powder, milk and other condiments and beverages, in order to prevent the aluminum dissolved into the food; 3. aluminum cooker should not be too long to cook the food should be controlled in the 4h or less. Do not fry food in aluminum pots; 4. Due to the strong corrosive effect of fluorine on aluminum, so in the high fluoride water quality, minimize the use of aluminum cookware. In acid rain areas, acid rain seepage into the ground, will cause groundwater acidification, acidification of the water of aluminum, copper, zinc, cadmium than neutral groundwater tens of times higher. Aluminum alloy Aluminum-based alloy composed of other elements. Pure aluminum conductivity, thermal conductivity and corrosion resistance is good, mainly used as electrical conductivity, thermal conductivity materials, but low strength, not suitable for structural materials. Aluminum can be formed with many chemical elements to improve the performance of alloys. Aluminum alloy specific gravity is light, the specific strength is close to alloy steel, than the stiffness over steel, plasticity is good, casting and machinability is also good, suitable for the manufacture of lightweight structural components, and therefore become indispensable materials for the aviation industry, in the transportation, construction, light industry, chemical industry, instrumentation, machinery and other sectors, and in the household appliances have been widely used. Aluminum and some aluminum alloys are treated by anodic oxidation and other methods, and various colors are produced by coloring process, which are widely used as packaging and decorative materials. Aluminum alloys are mainly used in warplanes, ships, missiles, rockets, satellites, combat vehicles, high-speed trains, automobiles, and high-rise buildings. Non-metallic materials Cement Cement: Cement is the most commonly used building material, it is also a silicate, ordinary cement is also known as Portland cement. It is made from limestone and clay, heated to the degree of sintering, and then crushed and ground to make, also known as the old days of the water portal, is from the English phonetic translation. Cement can be hardened in air or water Main properties of cement Main components of ordinary cement Reaction conditions Main equipment Main raw materials Clay Limestone Gypsum (auxiliary materials) Cement rotary kiln High temperature Tricalcium silicate:3CaO*SiO2 Dicalcium silicate:2CaO*SiO2 Tricalcium aluminate:3CaO*Al2O3 Hydrohardness 1. -What are the ingredients of cement mortar? 2. What is concrete made of? A mixture of cement, sand, and water. Ceramics are an ancient artifact made from clay or a mixture of clay with quartz and feldspar, etc., which is shaped, dried, and baked. Ceramics: Ceramics is a generic term, pottery and porcelain are not the same, pottery is the coarser texture of ceramic products. Porcelain is a fine texture, opaque or translucent ceramic products. In the metal surface covered with a layer of ceramic material, called ceramic coating. Vitreous Enamel: The surface of steel and other components is treated with ceramic materials to form a corrosion-resistant coating, which is called vitreous enamel. It can withstand high temperatures, but is prone to cracking. Ceramics Ceramics Types, Properties Reaction Conditions Production Process Main Raw Materials: Clay Mixing, Molding, Drying, Sintering, Cooling High Temperature Earthenware, Pottery, Stoneware, Porcelain Resistant to Oxidation, Acid and Alkali Corrosion, High Temperature, Insulation, Easily Molded Ceramic Materials 1.Conventional Ceramics Raw Materials: Natural Minerals (Rocks, Sand, Clay, ...) Preparation : Burning : The surface of steel and other fabricated parts is treated with ceramic materials to form a corrosion-resistant covering, which is enameled. ...) Preparation: Firing e.g. cement, glass, brick, refractory ...... 2. Several new ceramic materials (1) High temperature structural ceramics Raw materials: silicon nitride, silicon carbide, ...... Preparation: 1700 ℃ sintering Uses: automobile, aircraft engine Ceramic cutting tools Automobile, aircraft engines, ceramic cutting tools (ultra-thin) (2) Transparent ceramics (optical ceramics) Features: excellent optical properties, high temperature resistance (melting point of 2000 ℃ or more) Uses: High-pressure lamps (such as high-pressure sodium lamps operating temperature of 1200 ℃ life expectancy of 1-20,000 hours) Bullet-proof glass (3) Optical fibers (4) Bio-ceramics Features: corrosion-resistant, stable Uses: human organs, tissue repair, reconstruction (4) Bioceramics Features: corrosion-resistant, good stability (5) metal ceramics With the development of rockets, satellites and atomic energy and other high-tech, high-temperature materials have put forward new requirements, people hope that the material can be maintained at high temperatures, high strength and hardness, can withstand intense mechanical vibration and temperature changes, but also oxygen corrosion resistance and high insulation properties. However, neither high melting point metals nor ceramics can fulfill these requirements at the same time. Metal-ceramics are non-homogeneous composite materials consisting of ceramics and bonded metals. The ceramics are mainly high-temperature resistant oxides such as alumina and zirconia or their solid solutions, while the bonding metals are mainly high melting point metals such as chromium, molybdenum, tungsten and titanium. Ceramics and bonding metals are ground and mixed together, molded and sintered in an inactive atmosphere to produce cermets. Cermet has the advantages of both metal and ceramics, it has low density, high hardness, wear resistance, good thermal conductivity, and will not be brittle due to sudden cold or heat. In addition, in the metal surface coated with a layer of airtight, high melting point, poor heat transfer performance of the ceramic coating can also prevent the metal or alloy oxidation or corrosion at high temperatures. Metal ceramics are widely used in rockets, missiles, supersonic aircraft shells, combustion chambers, flame nozzles and other places. Organic synthetic materials 1. Plastic Plastic is the material that can be molded, or plastic material, it should include clay and plaster and other materials. At present, the concept of plastic has been exclusively referred to polymer synthetic materials. There is no strict line of demarcation between plastics, fibers and rubber, e.g. fibers are plastics until they are oriented and stretched, or rubber is plastics at low temperatures. Polyethylene, polypropylene, polyvinyl chloride and polybutylene are the most widely produced plastics because their raw materials are derived from oil or natural gas. Polyethylene is the representative, such as food packaging bags, oil drums are the most familiar sets. However, its main disadvantage is that it is susceptible to heat and aging in the air. The main disadvantages of PVC are poor heat resistance, deformation over 60℃, and a certain degree of toxicity. However, non-toxic PVC resins are now available. Rubber Natural rubber can be obtained from nearly 500 different plants, but mainly from tropical plants - rubber trees. Current production is 3 million tons per year. Natural rubber is superior to all current synthetic rubbers in terms of overall performance. Styrene-Butadiene Rubber is the largest variety of synthetic rubber Chloroprene rubber is also known as the "universal rubber" New materials (superconducting materials, nanomaterials, etc.) on the human lifestyle and quality of life, the impact of socio-economic development, as well as the impact on the environment.