Runny nose

What is the boiling and melting point of iron. Melting point of metals

In the metallurgical industry, one of the main areas is the casting of metals and their alloys due to the low cost and relative simplicity of the process. Molds with any shape and various dimensions can be cast, from small to large; It is suitable for both mass and customized production.

Casting is one of the oldest areas of working with metals, and begins around the Bronze Age: 7-3 millennium BC. e. Since then, many materials have been discovered, leading to advancements in technology and increased demands on the foundry industry.

Nowadays, there are many directions and types of casting, differing in technological process. One thing remains unchanged - the physical property of metals to pass from a solid to a liquid state, and it is important to know at what temperature the melting of different types of metals and their alloys begins.

Metal melting process

This process refers to the transition of a substance from a solid to a liquid state. When the melting point is reached, the metal can be in either a solid or liquid state; further increase will lead to the complete transition of the material into a liquid.

The same thing happens when solidifying - when the melting limit is reached, the substance will begin to transition from a liquid to a solid state, and the temperature will not change until complete crystallization.

It should be remembered that this rule applies only to pure metal. Alloys do not have a clear temperature boundary and undergo state transitions some range:

Solidus is the temperature line at which the most fusible component of the alloy begins to melt.
Liquidus is the final melting point of all components, below which the first alloy crystals begin to appear.

It is impossible to accurately measure the melting point of such substances; the point of transition of states is indicated by a numerical interval.

Depending on the temperature at which metals begin to melt, they are usually divided into:

Low-melting, up to 600 °C. These include tin, zinc, lead and others.
Medium melting, up to 1600 °C. Most common alloys, and metals such as gold, silver, copper, iron, aluminum.
Refractory, over 1600 °C. Titanium, molybdenum, tungsten, chromium.

There is also a boiling point - the point at which the molten metal begins to transition into a gaseous state. This is a very high temperature, typically 2 times the melting point.

Effect of pressure

The melting temperature and the equal solidification temperature depend on pressure, increasing with its increase. This is due to the fact that with increasing pressure the atoms come closer to each other, and in order to destroy the crystal lattice they need to be moved away. At increased pressure, greater thermal energy is required and the corresponding melting temperature increases.

There are exceptions when the temperature required to transform into a liquid state decreases with increased pressure. Such substances include ice, bismuth, germanium and antimony.

Melting point table

It is important for anyone involved in the metallurgical industry, whether a welder, foundry worker, smelter or jeweler, to know the temperatures at which the materials they work with melt. The table below shows the melting points of the most common substances.

Melting point table metals and alloys

Name	T pl, °C
Aluminum	660,4
Copper	1084,5
Tin	231,9
Zinc	419,5
Tungsten	3420
Nickel	1455
Silver	960
Gold	1064,4
Platinum	1768
Titanium	1668
Duralumin	650
Carbon steel	1100−1500
Cast iron	1110−1400
Iron	1539
Mercury	-38,9
Cupronickel	1170
Zirconium	3530
Silicon	1414
Nichrome	1400
Bismuth	271,4
Germanium	938,2
Tin	1300−1500
Bronze	930−1140
Cobalt	1494
Potassium	63
Sodium	93,8
Brass	1000
Magnesium	650
Manganese	1246
Chromium	2130
Molybdenum	2890
Lead	327,4
Beryllium	1287
Will win	3150
Fechral	1460
Antimony	630,6
titanium carbide	3150
zirconium carbide	3530
Gallium	29,76

In addition to the melting table, there are many other supporting materials. For example, the answer to the question what is the boiling point of iron lies in the table of boiling substances. In addition to boiling, metals have a number of other physical properties, such as strength.

Strength of metals

In addition to the ability to transition from a solid to a liquid state, one of the important properties of a material is its strength - the ability of a solid body to resist destruction and irreversible changes in shape. The main indicator of strength is the resistance that occurs when a pre-annealed workpiece breaks. The concept of strength does not apply to mercury because it is in a liquid state. The designation of strength is accepted in MPa - Mega Pascals.

The following groups exist strength of metals:

Fragile. Their resistance does not exceed 50MPa. These include tin, lead, soft-alkaline metals
Durable, 50−500 MPa. Copper, aluminum, iron, titanium. Materials of this group are the basis of many structural alloys.
High strength, over 500 MPa. For example, molybdenum and tungsten.

Metal strength table

The most common alloys in everyday life

As can be seen from the table, the melting points of elements vary greatly even among materials commonly found in everyday life.

Thus, the minimum melting point of mercury is -38.9 °C, so at room temperature it is already in a liquid state. This explains why household thermometers have a lower mark of -39 degrees Celsius: below this indicator, mercury turns into a solid state.

The most common solders in household use contain a significant percentage of tin, which has a melting point of 231.9 °C, so most solders melt at the operating temperature of the soldering iron 250−400 °C.

In addition, there are low-melting solders with a lower melt limit, up to 30 °C, and are used when overheating of the materials being soldered is dangerous. For these purposes, there are solders with bismuth, and the melting of these materials lies in the range from 29.7 - 120 °C.

Melting of high-carbon materials, depending on alloying components, ranges from 1100 to 1500 °C.

The melting points of metals and their alloys are in a very wide temperature range, from very low temperatures (mercury) to several thousand degrees. Knowledge of these indicators, as well as other physical properties, is very important for people who work in the metallurgical field. For example, knowledge of the temperature at which gold and other metals melt will be useful to jewelers, foundries and smelters.

Metal melting process

It should be remembered that this rule applies only to pure metal. Alloys do not have a clear temperature boundary and undergo state transitions in a certain range:

Solidus is the temperature line at which the most fusible component of the alloy begins to melt.
Liquidus is the final melting point of all components, below which the first alloy crystals begin to appear.

It is impossible to accurately measure the melting point of such substances; the point of transition of states is indicated by a numerical interval.

Depending on the temperature at which metals begin to melt, they are usually divided into:

Low-melting, up to 600 °C. These include zinc, lead and others.
Medium melting, up to 1600 °C. Most common alloys, and metals such as gold, silver, copper, iron, aluminum.
Refractory, over 1600 °C. Titanium, molybdenum, tungsten, chromium.

There is also a boiling point - the point at which the molten metal begins to transition into a gaseous state. This is a very high temperature, typically 2 times the melting point.

Effect of pressure

There are exceptions when the temperature required to transform into a liquid state decreases with increased pressure. Such substances include ice, bismuth, germanium and antimony.

Melting point table

Table of melting temperatures of metals and alloys

Name	T pl, °C
Aluminum	660,4
Copper	1084,5
Tin	231,9
Zinc	419,5
Tungsten	3420
Nickel	1455
Silver	960
Gold	1064,4
Platinum	1768
Titanium	1668
Duralumin	650
Carbon steel	1100−1500
	1110−1400
Iron	1539
Mercury	-38,9
Cupronickel	1170
Zirconium	3530
Silicon	1414
Nichrome	1400
Bismuth	271,4
Germanium	938,2
Tin	1300−1500
Bronze	930−1140
Cobalt	1494
Potassium	63
Sodium	93,8
Brass	1000
Magnesium	650
Manganese	1246
Chromium	2130
Molybdenum	2890
Lead	327,4
Beryllium	1287
Will win	3150
Fechral	1460
Antimony	630,6
titanium carbide	3150
zirconium carbide	3530
Gallium	29,76

There are the following strength groups of metals:

Fragile. Their resistance does not exceed 50MPa. These include tin, lead, soft-alkaline metals
Durable, 50−500 MPa. Copper, aluminum, iron, titanium. Materials of this group are the basis of many structural alloys.
High strength, over 500 MPa. For example, molybdenum and .

Metal strength table

The most common alloys in everyday life

As can be seen from the table, the melting points of elements vary greatly even among materials commonly found in everyday life.

Melting of high-carbon materials, depending on alloying components, ranges from 1100 to 1500 °C.

A malleable, silver-white metal with high chemical reactivity: iron corrodes quickly when exposed to high temperatures or high humidity. Iron burns in pure oxygen, and in a finely dispersed state it spontaneously ignites in air. Denoted by the symbol Fe (Latin Ferrum). One of the most common metals in the earth's crust (second place after).

See also:

STRUCTURE

Several polymorphic modifications have been established for iron, of which the high-temperature modification - γ-Fe (above 906°) forms a lattice of a face-centered cube of the Cu type (a 0 = 3.63), and the low-temperature modification - the α-Fe lattice of a centered cube of the α-Fe type ( a 0 = 2.86).
Depending on the heating temperature, iron can be found in three modifications, characterized by different crystal lattice structures:

In the temperature range from the lowest to 910°C - a-ferrite (alpha ferrite), which has a crystal lattice structure in the form of a centered cube;
In the temperature range from 910 to 1390°C - austenite, the crystal lattice of which has the structure of a face-centered cube;
In the temperature range from 1390 to 1535°C (melting point) - d-ferrite (delta ferrite). The crystal lattice of d-ferrite is the same as that of a-ferrite. The only difference between them is the different (larger for d-ferrite) distances between the atoms.

When liquid iron is cooled, primary crystals (crystallization centers) appear simultaneously at many points in the cooled volume. With subsequent cooling, new crystalline cells are built around each center until the entire supply of liquid metal is exhausted.
The result is a granular structure of the metal. Each grain has a crystal lattice with a certain direction of its axes.
With subsequent cooling of solid iron, during the transitions of d-ferrite to austenite and austenite to a-ferrite, new crystallization centers may appear with a corresponding change in grain size

PROPERTIES

In its pure form under normal conditions it is a solid. It has a silver-gray color and a pronounced metallic luster. The mechanical properties of iron include its level of hardness on the Mohs scale. It is equal to four (average). Iron has good electrical and thermal conductivity. The last feature can be felt by touching an iron object in a cold room. Because this material conducts heat quickly, it removes most of it from your skin in a short period of time, which is why you feel cold.
If you touch, for example, wood, you will notice that its thermal conductivity is much lower. The physical properties of iron include its melting and boiling points. The first is 1539 degrees Celsius, the second is 2860 degrees Celsius. We can conclude that the characteristic properties of iron are good ductility and fusibility. But that's not all. Also, the physical properties of iron include its ferromagnetism. What it is? Iron, whose magnetic properties we can observe in practical examples every day, is the only metal that has such a unique distinctive feature. This is explained by the fact that this material is capable of magnetization under the influence of a magnetic field. And after the end of the action of the latter, the iron, the magnetic properties of which have just been formed, remains a magnet for a long time. This phenomenon can be explained by the fact that in the structure of this metal there are many free electrons that are able to move.

RESERVES AND PRODUCTION

Iron is one of the most common elements in the solar system, especially on the terrestrial planets, in particular on Earth. A significant part of the iron of the terrestrial planets is located in the cores of the planets, where its content is estimated to be about 90%. The iron content in the earth's crust is 5%, and in the mantle about 12%.

Iron is quite widespread in the earth's crust - it accounts for about 4.1% of the mass of the earth's crust (4th place among all elements, 2nd among metals). In the mantle and crust, iron is concentrated mainly in silicates, while its content is significant in basic and ultrabasic rocks, and low in acidic and intermediate rocks.
A large number of ores and minerals containing iron are known. Of greatest practical importance are red iron ore (hematite, Fe2O3; contains up to 70% Fe), magnetic iron ore (magnetite, FeFe 2 O 4, Fe 3 O 4; contains 72.4% Fe), brown iron ore or limonite (goethite and hydrogoethite, FeOOH and FeOOH nH 2 O, respectively). Goethite and hydrogoethite are most often found in weathering crusts, forming so-called “iron hats”, the thickness of which reaches several hundred meters. They can also be of sedimentary origin, falling out of colloidal solutions in lakes or coastal areas of the seas. In this case, oolitic, or legume, iron ores are formed. Vivianite Fe 3 (PO 4) 2 8H 2 O is often found in them, forming black elongated crystals and radial aggregates.
The iron content in sea water is 1·10−5 -1·10−8%
In industry, iron is obtained from iron ore, mainly from hematite (Fe 2 O 3) and magnetite (FeO Fe 2 O 3).
There are various ways to extract iron from ores. The most common is the domain process.
The first stage of production is the reduction of iron with carbon in a blast furnace at a temperature of 2000 °C. In a blast furnace, carbon in the form of coke, iron ore in the form of agglomerate or pellets, and flux (such as limestone) are fed from above, and are met by a stream of forced hot air from below.
In addition to the blast furnace process, the process of direct iron production is common. In this case, pre-crushed ore is mixed with special clay, forming pellets. The pellets are fired and treated in a shaft furnace with hot methane conversion products, which contain hydrogen. Hydrogen easily reduces iron without contaminating the iron with impurities such as sulfur and phosphorus, which are common impurities in coal. Iron is obtained in solid form and is subsequently melted in electric furnaces. Chemically pure iron is obtained by electrolysis of solutions of its salts.

ORIGIN

Origin telluric (terrestrial) iron is rarely found in basalt lavas (Uifak, Disko Island, off the western coast of Greenland, near Kassel, Germany). At both points, pyrrhotite (Fe 1-x S) and cohenite (Fe 3 C) are associated with it, which is explained by both the reduction by carbon (including from the host rocks) and the decomposition of carbonyl complexes such as Fe(CO) n. In microscopic grains, it has more than once been established in altered (serpentinized) ultrabasic rocks, also in paragenesis with pyrrhotite, sometimes with magnetite, due to which it arises during reduction reactions. Very rarely found in the oxidation zone of ore deposits, during the formation of swamp ores. Findings have been recorded in sedimentary rocks associated with the reduction of iron compounds with hydrogen and hydrocarbons.
Almost pure iron was found in lunar soil, which is associated with both meteorite falls and magmatic processes. Finally, two classes of meteorites - stony-iron and iron - contain natural iron alloys as a rock-forming component.

APPLICATION

Iron is one of the most used metals, accounting for up to 95% of global metallurgical production.
Iron is the main component of steels and cast irons - the most important structural materials.
Iron can be part of alloys based on other metals - for example, nickel.
Magnetic iron oxide (magnetite) is an important material in the production of long-term computer memory devices: hard drives, floppy disks, etc.
Ultrafine magnetite powder is used in many black and white laser printers mixed with polymer granules as a toner. This uses both the black color of the magnetite and its ability to stick to the magnetized transfer roller.
The unique ferromagnetic properties of a number of iron-based alloys contribute to their widespread use in electrical engineering for magnetic cores of transformers and electric motors.
Iron(III) chloride (ferric chloride) is used in amateur radio practice for etching printed circuit boards.
Ferrous sulfate heptate (ferrous sulfate) mixed with copper sulfate is used to combat harmful fungi in gardening and construction.
Iron is used as an anode in iron-nickel batteries and iron-air batteries.
Aqueous solutions of ferrous and ferric chlorides, as well as its sulfates, are used as coagulants in the purification processes of natural and waste water in the water treatment of industrial enterprises.

Iron - Fe

CLASSIFICATION

Hey's CIM Ref1.57

Strunz (8th edition)	1/A.07-10
Nickel-Strunz (10th edition)	1.AE.05
Dana (7th edition)	1.1.17.1

The melting point of iron is an important indicator of the production technology of the metal and its alloys. When smelting raw materials, the physical and chemical properties of the ore and metal are taken into account.

The most common chemical element on Earth.

Physical and chemical properties of iron

Chemical element number 26 is the most abundant in the solar system. According to research, the iron content in the Earth's core is 79–85.5%. In terms of abundance in the planet's crust, it is second only to aluminum.
The metal in its pure form is white with a silver tint and is distinguished by its ductility. The presence of impurities determines its physical parameters. Iron tends to react to a magnet.
This chemical element is characterized by polymorphism, which occurs when heated. Increased concentrations of the metal are observed in areas of rock eruptions. Industrial deposits are formed as a result of external and internal processes occurring in the earth's crust.
River water contains approximately 2 mg/l of metal, and the figure for sea water is 100–1000 times less.
Iron has several oxidation states, which determine its geochemical characteristics in a certain environment. In its neutral form, the metal is found in the Earth's core.
Iron oxide is the main form found in nature, and iron oxide is located in the uppermost part of the earth's crust as part of sedimentary formations.
The content of chemical element No. 26 in minerals with an unstable composition increases with a decrease in the temperature gradient. Boiling occurs when heated to + 2861 °C. The specific heat of fusion is 247.1 KJ/kg.

Metal mining

Among the ores containing iron, the raw materials for industrial production are:

hematite;
goethite;
magnetite.

Goethite and hydrogoethite form formations in the weathering crust that are hundreds of meters in size. In the shelf zone and lakes, colloidal solutions of minerals form oolites (leguminous iron ores) as a result of precipitation.

Pyrite and pyrrhotite, widely occurring iron minerals in nature, are used as raw materials for the production of sulfuric acid.

Commonly occurring iron minerals also include:

siderite;
lellingitis;
marcasite;
ilmenite;
is violent.

The mineral melanterite, which is fragile green crystals with a glassy luster, is used in the pharmaceutical industry for the production of iron-containing preparations.

The main deposit of this metal is located in Brazil. Recently, attention has been focused on mining nodules present on the seafloor that contain iron and manganese.

Melting iron

What determines the melting point of iron?

Metal production involves various technologies for its extraction from ore raw materials. The most common method for smelting iron is the blast furnace method.

Before smelting the metal, it is reduced in a furnace at a temperature of +2000 °C. To extract impurities, flux is added, which decomposes when heated to an oxide, followed by combination with silicon dioxide and the formation of slag.

In addition to the blast furnace method, iron smelting is carried out by roasting crushed ore with clay. The mixture is formed into pellets and processed in a hydrogen reduction furnace. Further smelting of iron is carried out in electric furnaces.

Production of alloys in furnaces.

The properties of a metal depend on the purity of the material. For technically pure iron, the melting point is +1539 °C. Sulfur is a harmful impurity. It can only be extracted from a liquid solution. Chemically pure material is obtained by electrolysis of metal salts.

Metal alloys

In its pure form, this material is soft, so carbon is added to the composition to increase strength.

In metallurgy, iron alloys are called ferrous metals.

Depending on the components of the alloy, the properties of the materials change. The melting point of iron also changes in the presence of alloy components.

The specific heat of fusion of steel is 84 kJ. This indicator means that at the melting temperature of steel, 84 kJ of energy is required to transfer 1 kg of alloy from a crystalline to a liquid state.

Compounds of different metals form alloys. Specific heat of fusion cast iron is 96–140 kJ. Cast iron contains up to 4% carbon, 1.5% manganese, up to 4.5% silicon and impurities in the form of sulfur and phosphorus. There are white and gray alloys.

In white, part of the carbon is in the iron carbide compound. This alloy is brittle and hard. It is intended for the manufacture of structures and parts.

A gray alloy containing carbon in the form of graphite, it is easy to process. Pig iron is smelted from iron ore in blast furnaces. Melting of the ore is accompanied by the reduction reaction of iron from oxides with carbon.

Most substances can melt with increasing volume when heated. For cast iron with a volume of 1000 cm³, this figure is 988–994 cm³.

Cast iron is a raw material for the production of steel, characterized by carbon content (not higher than 2.14%).

Steel is classified according to its chemical composition:

alloyed;
carbon

Carbon steel contains impurities of sulfur, phosphorus and silicon. It is characterized by low electrical properties, low strength, and is easily susceptible to corrosion.

The presence of alloy additives gives steel new technical properties. The following are used as additional components:

molybdenum;
nickel;
tungsten;
chromium;
vanadium.

High-alloy steel contains no more than 10% additives. The alloy is durable. The technology for producing steel from cast iron allows us to obtain high-quality material for the production of:

Steel is used as a raw material in various industries. Without it, it is impossible to imagine aircraft manufacturing, shipbuilding, the automotive industry and many other production areas.

Each metal or alloy has unique properties, including its melting point. In this case, the object passes from one state to another, in a particular case, it becomes liquid from solid. To melt it, you need to apply heat to it and heat it until the desired temperature is reached. At the moment when the desired temperature point of a given alloy is reached, it may still remain in a solid state. As exposure continues, it begins to melt.

Mercury has the lowest melting point - it melts even at -39 °C, tungsten has the highest - 3422 °C. For alloys (steel and others) it is extremely difficult to determine the exact figure. It all depends on the ratio of the components in them. For alloys it is written as a numerical interval.

How the process works

Elements, whatever they are: gold, iron, cast iron, steel or any other, melt approximately the same. This occurs due to external or internal heating. External heating is carried out in a thermal furnace. For internal use resistive heating, passing electric current or induction heating in a high frequency electromagnetic field. The impact is approximately the same.

When heating occurs, the amplitude of thermal vibrations of molecules increases. Appear lattice structural defects, accompanied by the rupture of interatomic bonds. The period of lattice destruction and accumulation of defects is called melting.

Depending on the degree at which metals melt, they are divided into:

low-melting - up to 600 °C: lead, zinc, tin;
medium-melting - from 600 °C to 1600 °C: gold, copper, aluminum, cast iron, iron and most of all elements and compounds;
refractory - from 1600 °C: chromium, tungsten, molybdenum, titanium.

Depending on what the maximum degree is, the melting apparatus is selected. It should be stronger the stronger the heating.

The second important value is the boiling degree. This is the parameter at which liquids begin to boil. As a rule, it is twice the melting point. These values are directly proportional to each other and are usually given at normal pressure.

If the pressure increases, the amount of melting also increases. If the pressure decreases, then it decreases.

Characteristics table

Metals and alloys - indispensable forging base, foundry production, jewelry production and many other areas of production. No matter what the master does ( gold jewelry, fences made of cast iron, knives made of steel or copper bracelets), for proper operation it needs to know the temperatures at which a particular element melts.

To find out this parameter, you need to refer to the table. In the table you can also find the boiling degree.

Among the most commonly used elements in everyday life, the melting point indicators are as follows:

aluminum - 660 °C;
copper melting point - 1083 °C;
melting point of gold - 1063 °C;
silver - 960 °C;
tin - 232 °C. Tin is often used for soldering, since the temperature of a working soldering iron is exactly 250–400 degrees;
lead - 327 °C;
melting point of iron - 1539 °C;
the melting point of steel (an alloy of iron and carbon) is from 1300 °C to 1500 °C. It varies depending on the saturation of the steel with components;
melting point of cast iron (also an alloy of iron and carbon) - from 1100 °C to 1300 °C;
mercury - -38.9 °C.

As is clear from this part of the table, the most fusible metal is mercury, which at positive temperatures is already in a liquid state.

The boiling point of all these elements is almost twice, and sometimes even higher than the melting point. For example, for gold it is 2660 °C, for aluminum - 2519 °C, for iron - 2900 °C, for copper - 2580 °C, for mercury - 356.73 °C.

For alloys such as steel, cast iron and other metals, the calculation is approximately the same and depends on the ratio of components in the alloy.

The maximum boiling point for metals is Rhenia - 5596 °C. The highest boiling point is for the most refractory materials.

There are tables that also indicate metal density. The lightest metal is lithium, the heaviest is osmium. Osmium has a higher density than uranium and plutonium, if considered at room temperature. Light metals include: magnesium, aluminum, titanium. Heavy metals include most common metals: iron, copper, zinc, tin and many others. The last group is very heavy metals, these include: tungsten, gold, lead and others.

Another indicator found in the tables is thermal conductivity of metals. Neptunium is the worst conductor of heat, and the best metal in terms of thermal conductivity is silver. Gold, steel, iron, cast iron and other elements are in the middle between these two extremes. Clear characteristics for each can be found in the required table.

Melting point, along with density, refers to the physical characteristics of metals. Metal melting point- the temperature at which a metal changes from the solid state in which it is in its normal state (except mercury) to the liquid state when heated. During melting, the volume of the metal practically does not change, so the melting temperature is normal atmospheric pressure has no effect.

Melting point of metals ranges from -39 degrees Celsius to +3410 degrees. For most metals, the melting point is high, however, some metals can be melted at home by heating on a regular burner (tin, lead).

Classification of metals by melting point

Low-melting metals, whose melting point fluctuates up to 600 degrees Celsius, for example zinc, tin, bismuth.
Medium melting metals, which melt at a temperature from 600 to 1600 degrees Celsius: such as aluminum, copper, tin, iron.
Refractory metals, the melting point of which reaches more than 1600 degrees Celcius - tungsten, titanium, chrome and etc.
- the only metal that is in a liquid state under normal conditions (normal atmospheric pressure, average ambient temperature). The melting point of mercury is about -39 degrees Celsius.

Table of melting temperatures of metals and alloys

Metal	Melting temperature, degrees Celcius
Aluminum	660,4
Tungsten	3420
Duralumin	~650
Iron	1539
Gold	1063
Iridium	2447
Potassium	63,6
Silicon	1415
Brass	~1000
Low melting alloy	60,5
Magnesium	650
Copper	1084,5
Sodium	97,8
Nickel	1455
Tin	231,9
Platinum	1769,3
Mercury	–38,9
Lead	327,4
Silver	961,9
Steel	1300-1500
Zinc	419,5
Cast iron	1100-1300

When melting metal for the manufacture of metal castings, the choice of equipment, material for metal molding, etc. depends on the melting temperature. It should also be remembered that When alloying a metal with other elements, the melting point most often decreases.

Interesting fact
Do not confuse the concepts of “metal melting point” and “metal boiling point” - for many metals these characteristics are significantly different: for example, silver melts at a temperature of 961 degrees Celsius, and boils only when the temperature reaches 2180 degrees.

The melting point of a metal is the minimum temperature at which it changes from solid to liquid. When melting, its volume practically does not change. Metals are classified by melting point depending on the degree of heating.

Low-melting metals

Low-melting metals have a melting point below 600°C. These are zinc, tin, bismuth. Such metals can be melted at home by heating them on the stove or using a soldering iron. Low-melting metals are used in electronics and technology to connect metal elements and wires for the movement of electric current. The melting point of tin is 232 degrees, and zinc is 419.

Medium melting metals

Medium-melting metals begin to transform from solid to liquid at temperatures from 600°C to 1600°C. They are used to make slabs, reinforcements, blocks and other metal structures suitable for construction. This group of metals includes iron, copper, aluminum, and they are also part of many alloys. Copper is added to alloys of precious metals such as gold, silver, and platinum. 750 gold consists of 25% alloy metals, including copper, which gives it a reddish tint. The melting point of this material is 1084 °C. And aluminum begins to melt at a relatively low temperature of 660 degrees Celsius. This is a lightweight, ductile and inexpensive metal that does not oxidize or rust, therefore it is widely used in the manufacture of tableware. The melting point of iron is 1539 degrees. This is one of the most popular and affordable metals, its use is widespread in the construction and automotive industries. But due to the fact that iron is subject to corrosion, it must be additionally processed and covered with a protective layer of paint, drying oil, or prevent moisture from entering.

Refractory metals

The temperature of refractory metals is above 1600°C. These are tungsten, titanium, platinum, chromium and others. They are used as light sources, machine parts, lubricants, and in the nuclear industry. They are used to make wires, high-voltage wires, and are used to melt other metals with a lower melting point. Platinum begins to transition from solid to liquid at a temperature of 1769 degrees, and tungsten at a temperature of 3420°C.

Mercury is the only metal that is in a liquid state under normal conditions, namely, normal atmospheric pressure and average ambient temperature. The melting point of mercury is minus 39°C. This metal and its vapors are poisonous, so it is used only in closed containers or in laboratories. A common use of mercury is as a thermometer to measure body temperature.