Heat Treating

Normally end condition of the process is described instead of process used within heat treatment. This helps in focusing as which end product is needed or required so that efforts should be focused upon the ultimate outcome irrespective of the procedure followed.

Steel heating is sometimes utilized for altering carbon content. Upon heating of steel within oxidizing environment, oxygen makes a combination with iron for forming iron-oxide layer. This layer protects steel from the decarburization. Upon conversion of steel into austenite, oxygen & iron combine for forming slag that does not provide any protection against decarburization. Formation […]

Quenching steel results in transformation of austenite into martensite, it is not completely transformed. There are some of the crystals of austenite that remain unchanged and are not affected by quenching below martensite-finish temperature. This can further be transformed into martensite, through slow cooling of the metal at extremely lower temperatures. Normally, cold treating includes […]

It is a process of thermo-chemical diffusion within which alloying element, mostly nitrogen or carbon diffuse in to surface of monolithic metal. It results in an interstitial solid-solution that is harder as compared to base metal. This improves wear-resistance without any loss of toughness. Laser surface-engineering is surface treatment through high selectivity, versatility & novel […]

This technique is applied for hardening only some of the metal`s portion. It is different from differential hardening, in which heating is applied to entire metal and then cooled-down at varying rates. In the flame hardening technique, a separate portion of metal is kept subject to heating before quenching. This process is easier as compared […]

There are few techniques that allow various areas of object to get various heat-treatments. This is known as differential hardening and is common for high quality swords and knives. Its earliest examples include Chinese jian, Japanese katana, Nepalese khukuri etc. differential hardening technique uses insulating layer, for example clay layer for covering areas, required to […]

There are heat-treating methods that have been developed for altering properties of an object`s portion, not the whole object. These comprise of cooling various alloy areas at different cooling rates, quick heating of alloys within localized areas and quenching through thermo chemical diffusion. Quenching can also be done by tempering various areas of the object […]

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 […]

There are metals that fall under the classification of precipitation hardening. When quenching is performed upon some precipitation hardening-alloy, alloying elements of this alloy are trapped within solution, which results in soft metal. Performing aging for a solutionized-metal allow alloying elements for diffusing via microstructure & forming inter-metallic particles. Such particles nucleate & fall-out of […]