The tempering colors are used for judgment regarding tempered steels` final properties. Steel that is very hard is normally tempered within the light-to-dark straw range. Spring steels are often tempered towards blue color. There is variance regarding the final-hardness of tempered steel, which depends upon composition of steel. Thickness of oxide film also increases over […]

Martensitic steel in its un-tempered hard form is much brittle for use. One of the methods to alleviate this difficulty is tempering. Tempering of quenched parts is required for majority of its applications. To get toughness tempering includes heating of steel at less than the lower-critical temperature, which is often 400-1105F or 205-595C as per […]