A Guide to Metal Melting Points
The melting point of a metal is classed as the temperature that it changes from a solid to a liquid.
It is important to know the melting point of different metals because this affects how and where that metal can be used. It also affects fabrication and workability, so how the metal is manufactured.
What is the melting point?
The melting point of metal is the temperature at which it transforms from a solid to a liquid. The melting point is determined by the metal’s unique structure and how easily heat moves through it.
The melting point is also directly related to thermal conduction and thermal expansion. The lower the melting point, the more thermal conduction or expansion it demonstrates.
Melting point, thermal conduction and thermal expansion will all affect how the metal is used.
Why are metal melting points important?
It is important to understand metal melting points because this affects how the metal is alloyed. The alloying process must take place in the liquid state, as the base metal is combined with one or more alloying elements.
Melting point also affects how the metal is manufactured, including casting, welding and heat treatment. The casting equipment must have a higher melting point than the metal being cast, or it will be unable to fulfil its function. Melting point will also influence the effectiveness of welding and heat treatment, as more heat may be needed for success.
Metal melting points also dictate how that metal is used. A lot of industries require metals that can handle extreme heat, like the aerospace or oil and gas industries. Using a metal with a low melting point in high temperature environments will lead to component failure.
Why do metals have higher melting points?
It is well known that metals have higher melting points than other materials like plastic, for example. This is because metals have a strong lattice structure, with a strong molecular bond. That means it requires more energy (so heat) to break these bonds.
Lowest melting point metal
Mercury is the lowest melting point metal. It melts at -39°C, meaning it is in liquid form at room temperature. Other metals with a low melting point include Potassium at 63°C, Tin at 232°C and Lead at 327°C.
Highest melting point metal
Tungsten is the highest melting point metal, as it only melts at the extreme temperature of 3,399°C. Nickel is another metal with an extremely high melting point of 1,452°C. This is why nickel alloys are often used in high temperature applications.
Common metal melting points:
Aluminium = 660°C
Bronze = 913°C
Brass = 930°C
Copper = 1084°C
Steel = 1371°C – 1540°C (depends on alloy composition)
Stainless Steel = 1400°C – 1530°C (depends on alloy composition)
Get in touch with NeoNickel
It is vital to choose the correct metal for each application. In addition to oxidising resistance, it is very important to consider the melting point when choosing an alloy, as this can lead to component failure. Browse NeoNickel’s collection of alloys online and you can see the melting point as well as other relevant data. Get in touch to find out more.