Hinge is a joint. It is designed to join two 'arms' together while letting them move freely. A lever is when a pivot, load, effort is present. Although hinge itself is not a lever, but taking our biceps as an example, that would be a Class 3 lever.
Physical properties. Tungsten is a hard brittle solid whose color ranges from steel-gray to nearly white. Its melting point is the highest of any metal, 3,410Â°C (6,170Â°F) and its boiling point is about 5,900Â°C (10,600Â°F). Its density is about 19.3 grams per cubic centimeter. Tungsten conducts electrical current very well.
Tungsten carbide is naturally grayish in color, and because of its extreme hardness is a perfect base metal for physical vapor deposition (PVD) coatings. The rich luxurious color of black tungsten carbide results from a PVD process which deposits thin layers of color in a high temperature, vacuum environment.ith its rich color, lustrous shine, and sleek new designs, black tungsten is one of the hottest looks in tungsten wedding bands and is proving to be a popular choice for brides and grooms wanting wedding bands that express their individuality.