Low carbon steel may not harden.
Books:
1)G. Krauss, Steels - Heat Treatment and Processing Priciples, ASM
International, 1990.
2) K.-E. Thelning, Steel and its heat treatment, 2nd printing,
Butterworths, 1984.
3) ASM Metals Handbook and ASM Hanbook Series. For example: ASM Handbook,
Vol4, heat Treating, ASM International, 1991.
--
Antti S. Korhonen
Helsinki University of Technology
e-mail: as...@hut.fi
http://www.hut.fi/HUT/Treatment/alku.html
My understanding is that it's possible to case-harded low carbon steel
by wrapping the object in carbon and subjecting it to heat. If I don't
err, the carbon insinuates itself into the steel by a few molecules.
Many screws and steel dowel pins are case-hardened using this process, I
believe, and I can testify (as a machinist) that they have very hard
cases and soft cores.
It possible add carbon to low carbon steel. However, wrapping it into
carbon is not very good method in order to obtain reproducible results.
There are commercial gas carburizing furnaces, which can do the job. Even
plasma carburizing is carried out industrially. A typical layer thickness
is order of 1 mm, much more than few molecules. Gears, for example, are
often gas carburized to improve their wear resistance.
How sensitive to complexity of shape are such processes?
> How sensitive to complexity of shape are such processes?
Not very sensitive. Gas is surrounding the samples from all sides. The
only problem is the quenching, which should not be to severe. We have had
a small industrial gas carburizing furnace for about 30 years. It still
works fine.
I still think that the references that I provided are worth of reading. I
do not repeat them here. Use your favorite search engine to locate my
previous answer.