Metal that melts at room temperature

Melting point table

To find out what temperature is needed to melt metals, a table of increasing temperature indicators will help.

Melting table for medium-melting metals and alloys.

Melting table for refractory metals and alloys.

Classification of metals by melting point

In physics, the transition of a solid into a liquid state is characteristic only of substances with a crystalline structure. The melting point of metals is often indicated by a range of values; for alloys, it is difficult to accurately determine heating to the boundary phase state. For pure elements, every degree matters, especially if these are fusible elements,

doesn't matter. The summary table of t indicators is usually divided into 3 groups. In addition to low-melting elements, which heat up to a maximum of +600°C, there are refractory elements that can withstand heating above +1600°C, and medium-melting ones. This group includes alloys that form a melt pool at temperatures from +600 to 1600°C.

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.

Table of low-melting metals and alloys (up to 600C o)

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.

Table of medium-melting metals and alloys (from 600C to 1600C)

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.

What is melting point

Each metal has unique properties, and this list includes its melting point. When melting, the metal changes from one state to another, namely, from solid to liquid. To fuse a metal, you need to bring heat closer to it and heat it to the required temperature - this process is called the melting point. At the moment when the temperature reaches the desired level, it can still remain in a solid state. If you continue the impact, the metal or alloy will begin to melt.

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Melting and boiling are not the same thing. The point at which a substance transitions from solid to liquid is often referred to as the melting point of the metal. In the molten state, the molecules do not have a specific arrangement, but attraction holds them close together; in liquid form, the crystalline body leaves volume, but the shape is lost.

During boiling, the volume is lost, the molecules interact very weakly with each other, move chaotically in different directions, and separate from the surface. Boiling point is the process by which the pressure of metal vapor is equal to the pressure of the external environment.

In order to simplify the difference between critical heating points, we have prepared a simple table for you:

Melting point prediction (Lindemann criterion)

An attempt to predict the melting point of crystalline materials was made in 1910 by Frederick Lindemann [6]. The idea was the observation that the average amplitude of thermal fluctuations increases with increasing temperature. Melting begins when the vibration amplitude becomes large enough for neighboring atoms to partially occupy the same space.

The Lindeman criterion states that melting is expected when the rms value of the oscillation amplitude exceeds a threshold value.

The melting point of crystals is described quite well by the Lindemann formula [7]:

Tλ=xm29ℏ2MkBθrs2{displaystyle T_{lambda }={frac {x_{m}^{2}}{9hbar ^{2}}}Mk_{B}theta r_{s}^{2}}

where rs{displaystyle r_{s}} is the average radius of the unit cell, θ{displaystyle theta } is the Debye temperature, and the parameter xm{displaystyle x_{m}} for most materials varies in the range of 0.15-0.3.

Melting point - calculation

Lindemann's formula served as a theoretical basis for melting for almost a hundred years, but was not developed due to low accuracy.

At what temperature does it melt?

Metal elements, whatever they are, melt almost one to one. This process occurs when heated. It can be both external and internal. The first takes place in a furnace, and for the second, resistive heating is used, passing electricity or induction heating. The impact is almost the same. When heated, the amplitude of molecular vibrations increases. Structural lattice defects are formed, which are accompanied by the breaking of interatomic bonds. The process of lattice destruction and the accumulation of such defects means melting.

Different substances have different melting points. Theoretically, metals are divided into:

1. Low-melting - temperatures up to 600 degrees Celsius are sufficient to obtain a liquid substance.
2. Medium melting - requires a temperature of 600 to 1600 ⁰C.
3. Refractory are metals that require temperatures above 1600 ⁰C to melt.

Melting iron

The melting point of iron is quite high. A technically pure element requires a temperature of +1539 °C. This substance contains an impurity - sulfur, and it can only be extracted in liquid form.

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Without impurities, pure material can be obtained by electrolysis of metal salts.

Melting cast iron

Cast iron is the best metal for smelting. The high fluidity rate and low shrinkage rate make it possible to use it more effectively during casting. Next, consider the boiling point of cast iron in degrees Celsius:

• Gray - the temperature can reach 1260 degrees. When pouring into molds, the temperature can rise to 1400.
• White - the temperature reaches 1350 degrees. It is poured into molds at 1450.

Important! The melting rates of a metal such as cast iron are 400 degrees lower compared to steel. This significantly reduces energy costs during processing.

Melting steel

Melting steel at a temperature of 1400 °C
Steel is an alloy of iron with an admixture of carbon. Its main benefit is strength, since this substance is capable of maintaining its volume and shape for a long time. This is due to the fact that the particles are in an equilibrium position. Thus, the forces of attraction and repulsion between particles are equal.

Reference! Steel melts at 1400 °C.

Melting aluminum and copper

The melting point of aluminum is 660 degrees, which means that it can be melted at home.

Pure copper is 1083 degrees, and for copper alloys it ranges from 930 to 1140 degrees.

What does melting temperature depend on?

For different substances, the temperature at which the structure is completely reconstructed to the liquid state is different. If we take into account metals and alloys, then it is worth noting the following points:

1. Metals are not often found in their pure form. The temperature directly depends on its composition. As an example, we will indicate tin, to which other substances (for example, silver) can be added. Impurities make the material more or less resistant to heat.
2. There are alloys that, due to their chemical composition, can transform into a liquid state at temperatures above one hundred and fifty degrees. There are also alloys that can “hold” when heated to three thousand degrees and above. Taking into account the fact that when the crystal lattice changes, the physical and mechanical qualities change, and operating conditions can be determined by the heating temperature. It is worth noting that the melting point of a metal is an important property of a substance. An example of this is aviation equipment.

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Heat treatment, in most cases, almost does not change the resistance to heat. The only sure way to increase resistance to heat is to make changes to the chemical composition; this is why steel is alloyed.

Characteristics table

Metals and alloys are an indispensable basis for forging , foundry, jewelry and many other areas of production. Whatever the craftsman does ( gold jewelry , cast iron fences, steel knives or copper bracelets) , in order to work correctly, he needs to know the temperatures at which this or that 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:

1. aluminum - 660 °C;
2. copper melting point - 1083 °C;
3. melting point of gold - 1063 °C;
4. silver - 960 °C;
5. tin - 232 °C. Tin is often used for soldering, since the temperature of a working soldering iron is exactly 250–400 degrees;
6. lead - 327 °C;
7. melting point of iron - 1539 °C;
8. 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;
9. melting point of cast iron (also an alloy of iron and carbon) - from 1100 °C to 1300 °C;
10. 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 of metals is rhenium - 5596 ° C. The highest boiling point is for the most refractory materials.

There are tables that also indicate the density of metals . The lightest metal is lithium, the heaviest is osmium. Osmium has a higher density than uranium and plutonium when viewed 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 the 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.

Metals have a number of original properties that are unique to these materials. There is a melting point for metals at which the crystal lattice is destroyed. The substance retains its volume, but it is no longer possible to talk about the constancy of its shape.

Individual metals are found extremely rarely in their pure form. In practice, alloys are used. They have certain differences from pure substances. When complex compounds are formed, the crystal lattices combine with each other. Therefore, the properties of alloys may differ markedly from those of their constituent elements. The melting point no longer remains constant; it depends on the concentration of the ingredients included in the alloy.

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Which metal has the highest melting point

Tungsten is the most refractory metal, 3422 °C (6170 °F).
A hard, refractory, fairly heavy material of light gray color that has a metallic sheen. It is difficult to machine. At room temperature it is quite fragile and breaks. The fragility of the metal is associated with contamination with carbon and oxygen impurities.

Note! Technically, pure metal at temperatures above four hundred degrees Celsius becomes very ductile. Demonstrates chemical inertness and is reluctant to react with other elements. It occurs in nature in the form of such complex minerals as: hübnerite, scheelite, ferberite and wolframite.

Tungsten can be obtained from its ore, through complex chemical processing, as a powder. Using pressing and sintering, it is used to create parts of regular shape and bars.

Tungsten is an extremely resistant element to any temperature influences. For this reason, tungsten could not be softened for more than a hundred years. There was no furnace that could heat up to several thousand degrees Celsius. Scientists have been able to prove that this is the most refractory metal. Although there is an opinion that seaborgium, according to some theoretical data, has greater refractoriness, this is only an assumption, since it is a radioactive element and has a short lifespan.