Tin foil Tin foil Tin foil, also spelled tinfoil, is a thin foil made of tin. Actual tin foil was superseded after World War II by cheaper and more durable aluminium foil, which is still referred to as "tinfoil" in many regions. Foil made from a thin leaf of tin was commercially available before its aluminium counterpart. In the late 19th century and early 20th century, tin foil was in common use, and some people continue to refer to the new product by the name of the old one. Tin foil is stiffer than aluminium foil. It tends to give a slight
Foil bearing Foil bearing Foil bearings, also known as foil-air bearings, are a type of air bearing. A shaft is supported by a compliant, spring-loaded foil journal lining. Once the shaft is spinning fast enough, the working fluid (usually air) pushes the foil away from the shaft so that no contact occurs. The shaft and foil are separated by the air's high pressure, which is generated by the rotation that pulls gas into the bearing via viscosity effects. A high speed of the shaft with respect to the foil is required to initiate the air gap, and once this has been achieved,