Physical Properties of Cast Iron Enamel

Gray cast iron is mostly used for the manufacture of enamel products. The physical and chemical properties of cast iron have a great impact on the quality of enamel products. This article Nolifrit will introduce the physical properties of cast iron enamel in detail.

Physical properties of cast iron
1. Thermal expansion

The chemical composition of cast iron has a great influence on the thermal expansion coefficient. Carbon and silicon have the strongest influence. When the content of silicon decreases, the coefficient of expansion of cast iron is high; when the content of silicon increases, the coefficient of expansion of cast iron decreases. The other elements, such as manganese, scale and sulfur, have no significant effect on the expansion coefficient of cast iron.

2. The gettering ability of cast iron

In the process of heating and melting, the property that metal continuously absorbs the gas in contact with it is called gettering ability.

During the solidification process of molten iron, the gas absorbed by the metal continuously precipitates out in the form of bubbles. If the bubbles remain in the casting, the formed pores are called precipitating pores. During casting, this kind of pores are the densest in the upper part of the casting or the final solidified part, which is one of the reasons for the bubbles or pinholes in the porcelain layer.

In order to avoid the above problems, it is necessary to avoid the generation and absorbing of gas in the production of cast iron enamel.

3. Casting stress and measures to reduce deformation

Casting stress is divided into thermal stress, phase transformation stress and mechanical hindering stress according to the cause. After the cause of the stress is eliminated, the stress that still exists in the casting is called the residual stress. Bending deformation caused by thermal stress, the concave surface is always on the side where the casting cools slowly. This can be used as a basis for judging whether the cause of the deformation is improper placement of the casting during heating or a problem with the shape of the casting itself when the product is deformed during production.

The above is the summary of Nolifrit enamel material manufacturer on the physical properties of cast iron for enamel. I hope this little knowledge can be helpful to everyone. Nolifrit has 26 years of experience in the enamel industry. It is mainly engaged in enamel frit, enamel powder, electrostatic powder and enamel pigment. For more enamel knowledge, please follow us. For consultation and cooperation or free sample testing, please contact online customer service or directly call +8613574208778.