Explain me about the process of Carburising in metals?

Answer 1

kakani P wrote an excellent explanation but I wanted to add an example to help you furhter understand a practical application.

The tooth on the front of a backhoe bucket is a great piece to be carburized. It could be made totally of high carbon throughout but that would make it brittle and subject to break since it experiences many impacts and shock loads as it encounters rocks (or old concrete from foundations being demolished) and other debris in the soil. We still would like to have the surface hardened to reduce wearing but we still want the core to be ductile to prevent premature failure. Carburizing allows us to "have our cake and eat it too". We can make the surface wear resistent and hard but leave the core ductile and able to withstand large shock loads through the process of carburizing.

Answer 2

carburizing is the name of the process by which carbon is introduced into a metal.

The process of carburization works by implantation of carbon atoms in to the surface layers of a metal. As metals are made up of atoms bound tightly into a metallic crystalline lattice, the implanted carbon atoms force their way into the crystal structure of the metal and either remain in solution (dissolved within the metal crystalline matrix — this normally occurs at lower temperatures)
or
react with the host metal to form ceramic carbides (normally at higher temperatures, due to the higher mobility of the host metal's atoms).
Both of these mechanisms strengthen the surface of the metal, the former by causing lattice strains by virtue of the atoms being forced between those of the host metal and the latter via the formation of very hard particles that resist abrasion.

However, each different hardening mechanism leads to different solutions to the initial problem:
the former mechanism known as solid solution strengthening improves the host metals resistance to corrosion whilst imparting its increase in hardness;
the latter known as precipitation strengthening greatly improves the hardness but normally to the detriment of the host metals corrosion resistance.

Answer 3

What information are you needing? Are you carbonizing with a torch a furnace. Why and what purpose and I can give you a better anwser.