Stainless steel is composed of iron, carbon and chromium. Modern stainless steel may also contain other elements, such as nickel, niobium, molybdenum and titanium. The elements of nickel, molybdenum, niobium and chromium enhance the corrosion resistance of stainless steel.Know More
In 1913, English metallurgist Harry Brearly, who was working on a project to improve rifle barrels, discovered that adding chromium to low carbon steel gives it stain resistance. The addition of a minimum of 12 percent chromium to the steel is what makes it resist rust, or stain "less" compared to other types of steel.
The chromium in the steel combines with the oxygen in the atmosphere to form a thin, invisible layer of chrome-containing oxide, which is called passive film. As the sizes of chromium atoms and their oxides are similar, they pack tightly together on the surface of the metal, forming a stable layer only a few atoms thick.
Austenitic, ferritic and martensitic are the three main types of stainless steel. Austenitic stainless steels have an austenitic crystalline structure, which is a face-centered cubic crystal structure. Ferritic stainless steels have reduced corrosion resistance, due to their lower chromium and nickel content. However, ferritic steels generally have better engineering properties than austenitic grades and are typically more affordable. Martensitic stainless steels are not as corrosion-resistant as austenitic and ferritic steels, but they are extremely strong and can be hardened by heat treatment.Learn More
Nitrogen has five valence electrons. Valence electrons are the negatively charged particles found in the outer energy level of an atom, and are required to form chemical bonds.Full Answer >
Rubidium oxide is a yellow-brown or yellowish crystalline solid with a chemical formula Rb2O. It is also known as dirubidium oxide or rubidium (I) oxide. It is a strong base and reacts with water to produce rubidium hydroxide.Full Answer >
The chemical formula for cobalt(II) selenide is CoSe, according to Chemical Dictionary Online. It has a molar mass of 137.89 and a density of 7.65 grams per cubic centimeter. It has a melting point of 1,055 degrees Celsius. It appears as yellow hexagonal crystals.Full Answer >
The most flammable substance in the world is chlorine trifluoride, according to About.com. This substance is so flammable that it does not require an ignition source to combust.Full Answer >