View Feed
Coffee Room
Discuss anything here - everything that you wish to discuss with fellow engineers.
12829 Members
Join this group to post and comment.
N.Gowtham Raj
N.Gowtham Raj • Jan 28, 2012

Does Heat Treatment Process Changes Composition?

Hey guys... It happened to hear that, a heat treated component made up of steel(Medium carbon steel for instance) will have a different composition in the core and circumference...

It is a fact that the composition of the material changes slightly from point to point in a component but do HEAT Treatment has any effect over it??

I need some validity.....
Heat treatment of metals will not alter bulk chemical composition. However, it does alter microstructure wherein local compositional differences can happen.
N.Gowtham Raj
N.Gowtham Raj • Jan 29, 2012
Thank you... But...
It would be better if there are some references sir...... May be a journal or e book..
N.Gowtham Raj
Thank you... But...
It would be better if there are some references sir...... May be a journal or e book..
ISHAN TOPRE • Jan 29, 2012
To state simply, heat treating of steel makes the outer surface harder as the cooling rate is high. The inner core is usually soft. The heat treatment changes the circumferential micro-structure to become Martensite.
CE Designer
CE Designer • Jan 30, 2012
There are different types of heat treatments for metal. Some are used to relieve streses within the metal, some are used to surface harden it. Some are used to make them tough, while some are used to reduce the hardness. This is a very broad topic, but the situation you are describing in your query is called surface hardenning. Here the metal is heated and then cooling rapidly, usually in water. Carbon molecules that migrated to the surface during heating become trapped at the surface when the object is quenched. This makes the surface very hard and the core very tough. A hammer head is engineered this way. Think about it 😉
More info? Try to get your hand on Callister's Materials Science and Engineering.

NOTE: This type of heat treating cannot be performed on low-carbon steels. For low carbon steels Carburizing is used to surface harden.
Ammar Aziz
Ammar Aziz • Jan 31, 2012
if heat treatment of a material is carried out at some specific temperature range and pressure range then by altering the micro structure the depth of the added impurity also changes according to requirement

Share this content on your social channels -