Specific Weight of Porcelain, Its Properties, Types and Value Table

Porcelain is a type of ceramic that is impermeable to gas and water. This material is obtained by firing a coarse mixture of quartz, plastic clay, kaolin and feldspar at a high temperature. In a thin layer, porcelain is translucent, and when lightly struck it produces a high, characteristic ringing sound that can vary depending on the thickness and shape of the item.

The term “porcelain” can also be applied to technical ceramics, such as lithium, zirconium, boron-calcium, alumina and other types of porcelain, indicating the high density of a special-purpose ceramic material.

Table of the specific weight of porcelain

Since porcelain is a complex material, it is not possible to calculate its specific weight independently in field conditions. These calculations are carried out in special chemical laboratories. However, the average specific weight of porcelain is known and ranges from 2.15 to 2.5 g/cm³.

To simplify calculations, the table below shows the values of the specific weight of porcelain, as well as such a parameter as the weight of porcelain depending on the units of measurement.

Properties of porcelain

Porcelain has good performance characteristics for its field of use. Its density is usually in the range of 2.15-2.5 g/cm³, which corresponds to about 2150-2500 kg/m³. Porcelain has a sintered, dense body with low porosity and low water absorption.

One of the main quality factors of porcelain is its whiteness. First of all, this parameter depends on the type of impurities in the composition, which may include chromium, titanium, iron and other coloring compounds. The firing environment and kiln regime can also affect whiteness. If fine-grained particles are present in the impurities, the original material may have dark dots, the so-called specks, which spoil the appearance of the item.

The inclusion of ferric iron oxides gives the item a yellowish tint, while ferrous iron oxides give it a bluish tint. Greater whiteness can be achieved by adding kaolin, as well as by increasing the thickness of the glaze layer.

The translucency of porcelain depends on the amount of fluxes in the body, the firing temperature, and the degree of dispersion. Increased translucency can be achieved by reducing clay compounds in the composition, as well as quartz, mullite and gas bubbles.

The strength parameter is also important for porcelain. According to this parameter, two characteristics are distinguished: glaze strength and body strength. The latter parameter depends on the percentage ratio of glassy phases and crystalline phases, as well as on the porosity of the body itself and its thickness. The content of clay-type materials also affects strength. Items containing 50 to 54 percent of these materials have a higher mechanical strength parameter.

Types of porcelain

Two types of porcelain are distinguished depending on the composition:

• Hard porcelain. This porcelain contains a high share of kaolin, with quartz and feldspar used to form a dense fired body. To obtain this type, a temperature range from 1400 to 1460 °C is required. This type of product is intended for the manufacture of electrical insulators and everyday tableware. Bone china is usually treated as a separate variety with added bone ash; it is valued for whiteness, translucency and thin walls, but it is not a universal “hardest” type of porcelain.
• Soft porcelain. This porcelain contains from 25 to 40 percent kaolin, 45 percent quartz and 30 percent feldspar. To obtain this type, a temperature range from 1300 to 1350 °C is required. This type is intended for the manufacture of artistic items.