Selective Heat Treating

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 […]