Basic materials used in construction. Ten unique artificial materials with incredible properties. The classification of materials in relation to the development of finished products involves their division into main and auxiliary, without affecting

The concept of classification

• Classification of materials - a system of subordinate concepts in the field of materials science, used to establish relationships between groups of materials. It reflects the objective regularities studied by materials science.

General sign of material classification

• The most common feature of the classification of materials is the composition of their atoms and molecules.

• Based on this, all materials can be divided into simple and complex.

• Simple materials consist of substances formed by atoms of one element. An example of such substances can be graphite, diamond, sulfur, etc.

• Complex materials formed from molecules consisting of atoms of various elements - alloys, wood, water, glass, etc. chemically complex materials are divided into inorganic and organic.

• Organic materials include all complex materials based on carbon compounds, while inorganic materials include all the rest.

Classification of materials by functional feature

• By functional feature materials can be divided into two large groups: main and auxiliary.

Basic materials provide the specified specifications products - machines, mechanisms, structures, products, etc. - strength, power, speed, structural stability, etc. Auxiliary materials provide the parameters of structures and units during their operation (materials for lubrication of friction units, for cooling, for protection against erosion and corrosion), from physical and chemical effects, for decorative finishes and providing aesthetic parameters and design requirements, etc.

The use of multiple methodologies offers a cost-effective solution that is unparalleled in its rigor. Contact us to learn about your ore weight variability and make sure your processing scheme will handle your ore variability throughout the life of the project.

Determination of pitching quality after 20 years. quality score rocks on practice. Materials 1 Lesson Plan General Objectives To provide an overview of the wide variety of black and color materials. The classification of these materials will be discussed using development techniques and designation standards. General characteristics each major family of ferroalloys will be developed with a focus on embedding operations and usage properties. Specific Objectives  To know the operations of casting, setting and forming some common grades of ferrous and non-ferrous alloys.  Define and establish the designation of ferrous and non-ferrous metals and alloys in accordance with various relevant standards. Since prehistory, people have learned to prepare these minerals by washing, crushing, screening, removing fats and processing them by reduction, agglomeration on a mesh or granules to melt them to obtain iron and steel. IN historical era A flourishing iron and steel industry developed in many countries from local ore deposits and the proximity of forests that supplied fuel in the form of charcoal. Today, steel production is an indicator of national wealth and is the basis mass production in many industries such as shipbuilding, automotive, construction and public works, construction of machinery, tools and industrial and domestic equipment. The development of transport, especially at sea, has made international trade raw materials economically viable and helped to win the privileged position of countries with iron ore deposits near coal mines. Recall that the classification industrial metals and Alloys Families of Building Materials In the processing industry or the production of raw materials, the use of different grades of materials is of great industrial interest. Indeed, the objects around us that we process daily are made of a material chosen for its good adaptation to the function of the object, about which in question, and to the process used to give the object the desired shape. Therefore, the concept of a material is strictly inseparable from the interest that such a substance may have in obtaining the final object. The table below provides a qualitative comparison of the main mechanical properties of materials. Basic usage properties of each family Materials 4 Metallic materials, as the name suggests, have essentially metallic bonds, that is, provided in part by delocalized electrons. They are responsible for the good thermal and electrical conductive properties of metals. Metals are usually paramagnetic or even ferromagnetic. Their melting points and sprays are usually high. Metals are mostly ductile and relatively tenacious, and the combination of their tenacity and ductility is a major asset to their shaping. On the other hand, after shaping, metal alloys can easily obtain good mechanical strength by appropriate heat treatment due to phase precipitation. Because of their ductility, their resistance to fatigue can cause problems and they are more likely to corrode. Finally, metals are usually heavy and dense materials that are sometimes an obstacle. Properties of polymers. Polymers are made up of macromolecules with a covalent backbone held together by weak bonds. Their properties are highly dependent on the behavior of these weak bonds and develop significantly with temperature. They tend to have a low modulus of elasticity, and the elastic limit is lower, they will be brought to a higher temperature. They will be easy to form. They are also, despite their good deformability, good wear resistance. They are easy to install and have good corrosion resistance. Properties of technical ceramics Ceramics are characterized by strong bonds, which in practice translate into very good thermal stability and excellent elastic rigidity. As a result, the low ductility tendencies make these materials brittle, not very resistant, rather than ductile, but on the other hand resistant to wear. These materials have high temperatures melting point and good corrosion resistance. The quality of technical ceramics is usually expensive. Properties of composite materials Composite materials are materials that combine two or more different materials, sometimes belonging to two different classes, to obtain a combination of properties that take advantage of each. The most commonly used polymer matrices and fiber-reinforced composites, which have exceptional or directional specific properties. Finally, it is worth mentioning materials such as wood, cements and concretes, polymer, ceramic or metal foams, which are also composite materials. Design and designation of cast iron Ore: iron ore is found in the form of stone. Some farms are open, others are underground. Iron ore exists in four main combinations, namely:- oxygen oxygen- iron oxygen - hydrogen - iron carbon - iron carbon. The development of the font is processed ore in the form of a cylindrical cone refractory brick kiln, and a metal layer on the outside, the kiln itself is known. Pig iron is produced in blast furnaces from iron ore and coke, an increase in temperature leads to the melting of the filler and to a chemical transformation that produces a liquid melt and residues: slag and gas. The resulting product is not pure iron, but an alloy of iron and carbon from 2.3 to 4.5%, called cast iron. Depending on the processing, we get either white cast iron or gray cast iron. The cast created by the 1st merge act called has 3 users.  1st user merge: A cast intended for use in a 2nd merge.  2nd user: making a large piece by direct casting in molds.  3rd user: steel production  Benefits of cast iron. They allow complex molded parts to be realized because they have excellent fluidity. They have excellent machinability, graphite plays the role of lubricant. They are very stable in compression.  Disadvantages of cast iron. Lamellar gray cast iron is not very resistant to impact, and for other typefaces, the springiness problem is solved by the non-lamellar form of graphite. White fonts are used very little, except for the implementation of specific parts. They are heavy, but very brittle, this is due to the presence of cementite. Main melts of the 1st alloy Gray cast iron: carbon is in a free state in the form of graphite, it has a carbon content and very high silicon. It contains little silicon and carbon. It is used for casting parts with greater durability than cast iron parts. Processing of the second smelter iron: Principle: Cast iron obtained in blast furnace, contains too many impurities, for use in production it needs to be finalized, i.e. for cleaning, this operation obtained in the dome by merging pigs, the resulting metal and melting the 2nd melting. Various fonts obtained with the dome: according to the design of the load, we get:  gray iron, rich in carbon from 3.5 to 4%, and silicon from 2.5 to 2.7%; white cast iron low content carbon 2-2.5% and a little silicon Cast iron with high mechanical strength by inserting a steel strip into the dome of gray cast iron. Pig iron casting The second indicates, if necessary, the metallographic structure of the iron. The next number is 100 times the percentage of carbon; it is followed by the chemical symbols of the alloying elements in descending order of content, then by dash-separated numbers equal to the percentages of the main alloying elements in descending order. Design and designation of steel. Production of steel from scrap. The scrap melts together. After complete melting, the sample is taken and analyzed. If the carbon content is lower than that of the desired steel, cast iron is added. The introduction of lime into the bath will remove impurities in the form of slag. Materials The Bessemer process is a now extinct cast iron process used to produce inexpensive steel. This process is named after its inventor, Henry Besemer, who patented it. The process consists in air oxidation of undesirable chemical elements contained in cast iron to produce iron or steel. Thomas converter exhibited in Dortmund and development forecaster. This chapter often cites relevant international standards. The content used to express the compositions is always the weight percentage of the various constituents. Symbolic designation when used, It always begins with a capital letter. The steels intended for their use are not guaranteed to be suitable for heat treatment. Symbolic designation according to chemical composition Unalloyed steels: they have a manganese content of 1%, excluding low cut steels. Low alloy steels: the content of each alloying element is less than 5%; unalloyed steels with a manganese content of more than 1%; without cutting steels, excluding high speed steels. Follow the chemical symbols of the alloying elements in descending order of content; Tracking numbers separated by a dash, equal to the percentages of the main alloying elements in descending order. Materials 13 Numerical designation It consists of a number with 5 to 7 digits. Development and designation of aluminum alloys Industrial extraction of aluminum oxide from bauxite, Bayer process Physical transformation of bauxite to increase the contact surface for treatment with sodium hydroxide solution. Decantation, suspension filtration. Aluminate solution containing undissolved solids. Hydrolysis lasts about 2 days: aluminum hydroxide precipitates. A solid hydroxide primer must be added to create seed crystals. Filtration and concentration of the filtrate. It is not possible to reduce alumina with industrial reducers such as carbon, carbon monoxide or dihydrogen because aluminum is very reductive. The industry is busy lowering the cathode of the cell, a very powerful way to turn off. But alumina cannot be reduced in aqueous solution because aluminum is more reductive than water and it is the latter to be reduced instead of aluminum ions. In addition, aluminum oxide is difficult to alloy as all kinds of ionic structure. It is even used as a refractory coating. In industry, a molten mixture of 90% cryolite and 7% alumina is subjected to electrolysis. This mixture is much more fusible than pure alumina. The electrolysis of this mixture consumes almost like aluminum oxide and the carbon from the anode reacts with the oxygen formed. He notes, however, a consumption of about 30 kg per tonne of aluminum cryolite. Preparation and appointment Copper n is "present in" the earth's crust, with an average concentration of 55 ppm. The ore is considered rich with 1.8% pure copper. Copper is the second largest non-ferrous metal behind "aluminum and forward zinc, lead, nickel and tin" copper materials "is not a rare element, frequency in" earth's crust out of about 1%. The most important source of copper is the primary sulfur minerals lead sulfide and over 80% of the world's copper production. These minerals are mixed with sterile, so that the copper content of the rock rarely exceeds 2%. mine n is considered attractive if the content is less than 0.5%. In all cases, we must act with concentration and the first goal is to get rid of the ore-veining mechanical, physical and chemical methods. Mechanical Methods screening, crushing, grinding and sorting of minerals. Sulfur minerals are separated by flotation. In "using" selective hydrophobic agents such as "amyl potassium xanthates and" the same obtaining concentrates having a copper content in the range of 20 to 40%. Liquid matte in the presence of oxidized silica with air pressure flow. This metal is called blister copper and contains 1% impurities. This n cannot be used and must be specified. Copper alloys Designation In the case of a copper alloy, it is followed by the chemical symbols of the alloying elements of each followed by their mass percentage in descending order. The percentage of minority elements is not necessarily included in the designation, but is nonetheless specified in the definition standard of the respective standard. Explain the following notations by indicating the type of alloy, the main elements and the additive with their relative percentages, when possible. Give the designation for white-core malleable iron whose tensile strength is 700 MPa and the elongation at break is 2%. Fill in the missing information in the following table. Clean up the stages of extracting carbon from ore. Summary for the next part of chapter 1 of Jean Mathon's book Welding Technology.

Function classification of industrial products

other groups of classification features of materials

• By appointment(by industrial sectors, production facilities);
• (materials for deformation, casting, cutting);
• According to the degree of readiness for use(raw materials, semi-finished products);
• (main material, material for auxiliary processing);
• According to the level of application efficiency(wholesale prices, manufacturability, serialization);
• According to resource suitability and scarcity, if possible, replacement with other materials;
• According to the degree of safety of use;
• According to ecological parameters.

Material classification by appointment

• Material classification comes on purpose from the composition of the functions that the material performs

• (ensuring structural strength, sound insulation, corrosion resistance, product safety - packaging, packaging, radiation protection_).

According to the manufacturability of processing and assembly

• Material separation on manufacturability of processing and assembly takes into account the complexity of obtaining parts, assemblies, assemblies and is associated with the cost of the product. Some materials are obtained by gluing, some by pressure, others by casting or welding.

According to the degree of readiness of materials for use

• Readiness degree material to use determined its geometric dimensions and shape, the state of delivery.

• To give the product the required properties and shape, the materials are subjected to additional processing (mechanical, impregnation, heating, crushing, sintering, etc.), which significantly affects the cost of labor, time, and material consumption.

• According to the degree of readiness of materials divided into four groups:

• .Raw materials and semi-finished products, which are later used as materials;
• .Materials for obtaining semi-finished products and products or used as raw materials for other material;
• .Semi-finished products for the manufacture of finished products;
• .Finished products used to complete more complex products.

Material classification in relation to the production of finished products

• Material classification in relation to the production of finished products involves their division into main and auxiliary, not affecting and affecting the processing modes or tool life.

Separation of materials by efficiency level

• Separation of materials by efficiency level application is based on the capital and current costs of obtaining and processing, the technical level of production, the quality of raw materials, etc.

Division of materials

• Division of materials in terms of safety and environmental parameters provides for the possibility of assessing damage from a negative impact on human health and the environment.

• Classification according to resource suitability and scarcity, if possible, to replace it with other materials, takes into account the frequency of repair of products, the situation on the market for materials.

Topic 2. Metals and alloys

• Metallic materials by chemical composition are often called simply metals, which are divided into non-ferrous and ferrous.

• Alloy - a material with a homogeneous macrostructure formed as a result of the solidification of a melt of chemically dissimilar substances. Depending on the amount of impurities and additives, metals are divided into pure, technical purity and alloys.

Non-ferrous metals

• Non-ferrous metals share:

• lungs- with low density:

• Al aluminum;
• Mg magnesium;
• Ti titanium;
• Be beryllium);
• fusible- with a melting point lower than that of iron:
• Zn zinc,
• cd cadmium,
• Sn tin, Pb palladium,
• Bi bismuth,
• Sb antimony),

Metal properties

• Metals (from Greek Metallon - ore, metal) are substances characterized by high electrical and thermal conductivity, the ability to reflect electromagnetic waves well, and plasticity.

Mechanical properties of metals and alloys

• Cold brittleness

• brittle destruction

• Ductile fracture

• crack resistance

• Reliability

• Durability

• wear resistance

Materials are one of the most important elements of the production cycle of any organization; they are objects of labor that are used to manufacture products, perform work, and provide services. Their peculiarity lies in the fact that, participating in the production process, materials are completely consumed in each of its cycles and fully transfer their value to newly created products (works, services).

In contrast to fixed assets, material resources participate in the production process once and transfer their value to the product being produced in full. Therefore, after each production process, they have to be renewed.

On manufacturing enterprises material resources in the cost of manufactured products occupy a significant share. Therefore, their accounting, storage and rational use in the production process is important in improving the efficiency of the financial and economic activities of the enterprise.

The main tasks of accounting inventories are:

Proper and timely documentation of all operations for the movement of material resources;

Control over the safety of material resources in places of their storage and at all stages of movement;

Compliance monitoring established norms consumption of material resources in the production process;

Timely identification of surplus material resources to be sold to other enterprises, etc. .

Necessary conditions effective control over the safety and rational use of material resources at the enterprise are:

Proper organization of logistics;

Good condition of storage and weighing facilities;

Use of progressive norms of consumption of material resources;

A set of persons financially responsible for the reception, preservation and release of material resources.

For the correct organization of accounting for material resources, their scientifically based classification, evaluation and choice of accounting unit are important.

Manufacturing companies use a wide variety of materials. Some are completely consumed in the production process (raw materials and basic materials, semi-finished products, components, etc.), others only change their shape (lubricants, varnishes, paints), others are included in products without any external changes (spare parts ). Depending on the functional role and purpose in the production process, they are divided into groups: raw materials; purchased semi-finished products and components, structures and parts; fuel; container and container materials; spare parts; Other materials; materials transferred for processing to the side; Construction Materials; inventory and household supplies.

According to the chart of accounts accounting for each of the specified groups on account 10 "Materials" the separate subaccount is intended.

The group "Raw materials and materials" is additionally subdivided into subgroups: "Raw materials and basic materials" and "Auxiliary materials".

Raw materials and basic materials form the material basis of manufactured products. The raw material is the product Agriculture(grain, wool, cotton, fruits, berries, vegetables) and extractive industries (oil, ore, gas, etc.). The main materials are considered products of the manufacturing industry (flour, sugar, fabric, metal, leather, etc.).

Auxiliary materials are not materially included in the manufactured products, but are used for the operation of technological equipment (lubricants and cleaning materials), for household needs and current repairs (nails, paints, etc.), for stationery needs (paper, forms of documents and registers, pens , pencils, etc.), for medical care (medicines, bandages). .

It should be borne in mind that the division of materials into basic and auxiliary is possible only at a particular enterprise. This is due to the fact that the same material at one enterprise can be attributed to the composition of the main materials, and on the other - auxiliary. For example, fuel at a power plant for technological purposes is the main material, and at a manufacturing enterprise for space heating it is an auxiliary material; starch in the confectionery industry is part of the main materials, and in the textile industry - auxiliary.

Purchased semi-finished products, components, structures and parts are objects of labor manufactured by another enterprise and intended for further processing at this enterprise. In the manufacture of products, they play the same role as the main materials, i.e. constitute their material basis.

Returnable production waste - the remains of raw materials and materials formed in the process of their processing into finished products, which have completely or partially lost the consumer properties of the original raw materials and materials (sawdust, shavings, etc.).

According to their functional role in the production process, they are the main materials (various fillings in the confectionery industry, malt in brewing, yarn in textile production, motors in mechanical engineering). The need to allocate them to a separate accounting group is due to an increase in their specific gravity at large enterprises in connection with the development of specialization and cooperative production.

Enterprises can also have semi-finished products of their own production, which are recorded either on a special account 21 "Semi-finished products of their own production", or as part of work in progress.

Fuel in its functional role and purpose in the production process is one of the types of auxiliary materials. Due to its significant share in the total mass of auxiliary materials and its great national economic importance, it is allocated to a separate accounting group.

Fuels are divided into three groups: process fuels used for the manufacture of products, for example, for baking ovens; energy fuel used to generate steam in the steam power industry and electricity at the plant's substations; household, used for space heating.

Containers and container materials are used for packaging, transportation and storage of materials, semi-finished products and finished products.

The conditions for the supply of goods may provide for certain types of containers that are subject to mandatory return to suppliers or delivery to container-collecting and container-repairing enterprises. Returnable packaging refers mainly to reusable packaging. In some cases, in order to ensure the timeliness of the return of containers, the supplier collects a deposit from the buyer, which is credited to him after the delivery of the container during the final settlement. Such packaging is called a pledge depending on the cost and service life. The packaging is accounted for either as part of fixed assets or as part of production stocks.

Inventory and household supplies are part of the organization's inventory used as means of labor for no more than 12 months or the normal operating cycle if it exceeds 12 months (inventory, tools, etc.).

Spare parts are purchased and used to repair and replace worn parts of machines, equipment, vehicles, etc.

At manufacturing enterprises, other materials are allocated to a special group, which include: production waste (trimmings, shavings, flaps, etc.); material assets received from the liquidation of fixed assets that cannot be used as materials, fuel or spare parts at this enterprise (scrap metal, waste materials); worn tires and scrap rubber etc. .

In addition, materials are classified according to their technical properties and are divided into groups: ferrous and non-ferrous metals, rolled products, pipes, etc.

The indicated classifications of inventories are used to build synthetic and analytical accounting, as well as to compile a statistical report on the balances, receipts and consumption of raw materials and materials in production and operational activities.

On the hotel sub-account of account 10 "Materials", materials transferred for processing to the side are taken into account. The cost of such materials is later included in the cost of products obtained from processing.

Construction Materials are used by developers directly in the process of construction and installation work.

At manufacturing enterprises, inventory and household supplies, i.e., means of labor, which are included in the composition of funds in circulation, are also taken into account on a separate sub-account.

At manufacturing enterprises, in addition, materials that do not belong to them can be taken into account. Accounting for such materials is kept on off-balance accounts: 002 "Inventory accepted for safekeeping"; 003 "Materials accepted for processing".

The above groupings are still insufficient for a comprehensive control over the state and movement of materials. Their accounting and control should be carried out not only by groups, subgroups, but also by each name, type, size, grade, etc. Therefore, the general classification of materials is detailed in the nomenclature-price tag.

The nomenclature-price tag is a systematized list of materials used in the enterprise. Usually, it indicates the item number of the material, name, grade, size and other characteristics, as well as the unit of measurement and the discount price. The nomenclature-price tag is used as a reference by almost all departments of the enterprise (logistics department, etc.). The nomenclature-price tag also indicates a fixed accounting price and a unit of measure for materials. When used in computer accounting, the content of the nomenclature-price tag can be significantly expanded by introducing into it indicators of the stock rate, numbers of synthetic accounts and sub-accounts, and some other constant signs. The coding of the price tag item is usually carried out according to a mixed ordinal-serial system, using seven-eight-digit codes. The first two characters indicate a synthetic account, the third defines a sub-account, one or two of the following characters indicate a group of materials, the rest - various signs, characteristics of the material. The information contained in the nomenclature-price tags refers to conditionally constant. It is written to machine media and used repeatedly to obtain the necessary output data.

Analytical accounting of materials is organized in strict accordance with the construction of the nomenclature directory, and the fixed nomenclature number is compulsorily affixed to all documents related to the registration of the receipt and issue of the relevant materials. .