What Elements Are in Calcium Sulfide?

What elements are in calcium sulfide?

The chemical compound CaS is formed by the chemical combination of two elements: one atom of calcium combined with one atom of sulphur. It is a white substance crystallizing in cubes like rock salt.

Sulfur is a very common element found in many different metals and in some ores, including those from the volcanic regions of Italy, Sicily, Greece, the Middle East, Mexico, Japan, Chile, Peru, and the United States [16,18]. It is also present in several minerals such as galena (PbS), zinc blende (ZnS), cinnabar (HgS), and iron pyrites (FeS2), and gypsum (CaSO4).

A sulfide is a solid with a number of single covalent bonds. The number of these covalent bonds is usually a factor of six, but the total number of bonding electrons is a constant.

During solidification, sulfur forms sulfides and these sulfides are very toxic. They are responsible for a wide range of metallurgical problems, such as brittleness, cracking, and microsegregation.

These sulfides are especially detrimental to high-speed machining of steel, because they form stringers or platelets that are very difficult to remove from a surface. The treatment of sulfides with calcium eliminates their harmful effect in two ways:

First, sulfide inclusions can be reduced to very low contents ( 0.005%S). This can significantly reduce the amount of sulfides that are formed during casting and solidification and, at the same time, enables the forming of (Ca,Mn)S inclusions that do not deform to elongated stringers. This can have a huge impact on through-thickness ductility and toughness of hot-rolled steels.