A spring is a flexible machine element that stores mechanical energy when subjected to tensile, compressive, bending, or torsional forces.
Hooke‘s law states that the force applied on the spring is directly proportional to its deflection provided that it is within the elastic range.
The most common form of spring is a helical spring which is made from a wire with a circular cross-section.
The main objective of spring design is to determine the right combination of spring geometry and material that will achieve safe working stress at a practical cost.
Spring materials are made from alloys such as steel, stainless steel, copper alloys, and nickel alloys.