Steel is a popular and versatile metal that has a wide range of uses, from construction and transportation to medical equipment and household appliances. The melting point of steel is an important property of the metal because it determines how the steel will behave when heated and cooled.
In this article, we take a closer look at the melting point of steel and how it is affected by steel grade and the presence of impurities.
What Is the Melting Point of Steel?
The melting point of steel occurs at higher temperatures, around 2,200-2,500 Fahrenheit (°F) or 1,205-1,370 Celsius (°C).
Most steel has other metals added to tune its properties, like strength, corrosion resistance, or ease of fabrication. Steel is just the element iron that has been processed to control the amount of carbon. Iron, out of the ground, melts at around 1510 degrees C (2750°F). Steel often melts at around 1370 degrees C (2500°F).
Impurities such as sulfur, phosphorus, and lead can lower the melting point of steel. These impurities form inclusions, which are small clusters of atoms surrounded by a matrix of pure steel. Inclusions make the steel more brittle and can lower the melting point by up to 50°C (90°F).
In order to produce steel with a high melting point, the steel must be cleaned of impurities through a process called deoxidation. In this process, elements such as aluminum, silicon, or manganese are added to the steel, which reacts with the impurities and removes them from the steel.
Depending on the presence and percentage of an alloying element, the melting point of steel varies.
Different Types of steel and their Melting Points
|Type of Steel||Melting Point (°C)||Melting Point (°F)|
|Low carbon steel||1410°C||2570°F|
|Medium carbon steel||1425-1540°C||2600-2800°F|
|High carbon steel||1425-1540°C||2600-2800°F|
Please note that this is just a general guide and the actual melting point of a particular steel may vary depending on its composition and manufacturing process.
Let us explore the melting point of steel with the above-mentioned main types of steel:
What is the Melting Point of Carbon Steel?
The melting point of carbon steel is around 1371-1540°C (2500-2800°F) with variations based on carbon content.
The amount of carbon in carbon steel can vary, with low-carbon steel containing up to about 0.3% carbon, medium-carbon steel containing 0.3-0.6% carbon, and high-carbon steel containing more than 0.6% carbon. Apart from carbon, it also contains traces of copper (0.6%), manganese (1.65%), and silicon (0.6%). The more carbon that is added to the steel, the higher its melting point will be.
Low-carbon steel typically has a melting point of around 1410°C (2570°F), while medium-carbon steel typically has a melting point of around 1490-1530 °C (2600-2800 °F). High-carbon steel has the highest melting point of around 1425-1540 °C (2600-2800 °F).
However, it is important to note that these are approximate melting points and the actual melting point of a particular steel will depend on the purity and composition of the steel.
In addition to the carbon content, other factors can also affect the melting point of carbon steel. Such as Impurities, such as sulfur and phosphorus, can lower the melting point of steel. The presence of alloying elements like Nickel, Manganese, Chrome, etc. in the steel can also affect the melting point.
What is the Melting Point of Stainless Steel?
The melting point of stainless steel containing 10.5% to 11% chromium is 1510°C (2750°F).
The melting point of Stainless-Steel grade 304 ranges from 1400-1450°C; grade 316 ranges from 1375-1400°C; and grade 321 ranges from 1400-1425°C. The melting point of DSS grade 2205 ranges from 1385-1440°C.
The melting point of other stainless-steel grades are:
- Grade 304. 1400-1450°C (2552-2642°F)
- Grade 316. 1375-1400°C (2507-2552°F)
- Grade 430. 1425-1510°C (2597-2750°F)
- Grade 434. 1426-1510°C (2600-2750°F)
- Grade 420. 1450-1510°C (2642-2750°F)
- Grade 410. 1480-1530°C (2696-2786°F)
What Is the Melting Point of Alloy Steel?
These are of two groups low alloy steels and high alloy steels, the former being the more commonly used of the two. Low alloy steel’s melting point is 1432°C (2610°F) and that of high alloy steel is 1415°C (2600°F).
Alloy steels containing 1 to 50% of alloying element is known as alloy steel. An alloy steel is a steel that contains other elements such as manganese, nickel, or molybdenum, which gives it different properties than carbon steel. The melting point of alloy steel also varies depending on the specific type and alloying elements.
What Is the Melting Point of Tool Steel?
The melting point of this type varies in the range of 1400 to 1425°C (2550 to 2600°F). As the name suggests, this type is mainly used to make tools as it is the hardest grade of steel. It is a harder version of carbon and alloy steels with a carbon content of 0.7 to 1.4%.
Manganese, chromium, nickel, tungsten, molybdenum, phosphorus, and sulfur are some of the elements that are added in various proportions to make other types of tool steel.
Factor Affecting to Melting Point of Steel
There are several factors that can affect the melting point of steel:
- Composition. The type and amount of alloying elements in steel can affect the melting point. For example, high-carbon steels have a higher melting point than low-carbon steels.
- Impurities. The presence of impurities, such as sulfur and phosphorus, can lower the melting point of steel.
- Temperature. The temperature at which steel is heated can also affect its melting point.
- Pressure. High pressure can increase the melting point of steel, while low pressure can lower it.
- Cooling rate. The rate at which steel is cooled can affect its microstructure and, therefore, its melting point. Rapid cooling can lead to the formation of hard and brittle martensite, while slow cooling can lead to the formation of soft and ductile pearlite.
- Thermal treatment. Various thermal treatments like Annealing, normalizing, hardening, tempering, etc. can change the microstructure and affect the melting point of steel
It’s important to note that the melting point of steel varies depending on the specific type of steel and can range from around 2500-2800°F or 1371-1540°C.