One of the grace of God Almighty on the human being is to make matter transform from one form to another in order to benefit from it, otherwise the rate of benefit from it would have been limited, because due to the change in the shape of water in nature, living organisms can benefit from it, when it is steam, it softens the temperature of the atmosphere and moistens it and makes it suitable for life Also, this steam may turn into water during the condensation process to become a liquid that runs in water bodies, and also man was able to exploit these properties of some other materials such as minerals that a mixture of which can .be prepared after melting them to homogeneous together

Concept of melting point :

Melting point is defined as the temperature at which a substance turns from a solid to a liquid state; As each pure solid has its own melting point and differs from other materials.

Several factors influence the melting point of a material :

- Atmospheric pressure : As the atmospheric pressure increases, the melting point increases, and thus the temperature required to complete the melting process increases.

- The purity of the material : when a substance is composed of a single element, the fusion process is homogeneous, whereas if it consists of a group of elements and each element has a certain melting point, which makes the process heterogeneous, and scientists were able to rely on this information to know the purity of the substance if it melted at a temperature Specific, it is pure, while if it melts at different degrees, it consists of a mixture of substances.

For example, steel is a mixture of iron and a small amount of carbon and other elements. Steel is a hard and strong metal, so it is used in the construction of bridges and construction.

Steel fabrication method :

A method called the electric arc through which the metals used are melted (i.e., they reach the melting point), then the metals are mixed and the result is a steel metal that has many uses, as knowing the melting point of the materials two or more materials can be mixed with heat and a new compound is formed that has many uses that benefit us in our life Daily.