Normalising

Heat treatment followed by air cooling, of heavily forged and cold formed steel, intended to return the structure to “normal”.

When plain carbon or low alloy steels are required to be softened sufficiently to allow a moderate degree of cold forming or machining or to homogenise the ‘crystal structure, normalising may be employed. This treatment involves heating the work piece to above the upper critical temperature and holding at temperature for sufficient time to allow full austenitisation to occur, then air cooling or cooling in a controlled atmosphere to ambient temperature. Whilst not producing the same degree of softening as the annealing treatments, normalising has a lower cost and is a far quicker method.