Benefits and principles of Forging
Forging ,the art of the forming or shaping by hammering or pressing ,is undoubtedly the oldest mechanical method in the metal working art.It takes advantage of one of the most valuable propertites of metal -its plasticity at high temperature,the capability to be deformed by mechanical work .
Forging ,while producing desired shape,actually kneads the metal .This kneading ,or hot working refines the cast structure.and improves mechanical properties .Forging heals the porosity of the cast ingot and favourably orients the flow lines with respect to major stress fields ,where maximum tesile strength,toughness, and fatigue resistance are important .
Because of demands for strenth and toughness in metal ,development of the optimum combination of these properties is a vital requirement. No other process for working metal can equal forging in this respect .The products of the ancient hand forger depended upon his manual skill and was limited by his tools ,equipment ,and available materials.His methods were supplanted by mechanically operated hammers and presses.Today the forger has at his command improved equipment and instruments for the control of the heating ,handing ,working ,and testing of greatly improved materials .
Hot forging is the woking of metal in a plastic state,as the metal is formed by compressive forces ,the stock acquires qualities of soundness ,homogeneity,flow-line characteristics, and strength not readily attaineable in cast or welded shapes .this high quality ,together with open die forging’s versatility in producing all sizes and shapes ,makes it an essential modern technology .
with every load applied to a metal ,that metal undergoes a change of shape .The change may range from minute to gross as applied force increases .If he metal returns to its original shape after removal of the applied loading. Its behavior is said to be elastic ,and there are no permanent effects of the force application once it has been removed .However ,if the metal retains a shapes change after removal of the applied force ,then some plastic or inelastic deformation has resulted .
