Tudors - Download the EBook Queen AdelaideInformational Site Network Informational
Privacy
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

Flange Shields For Furnaces
Such portable flame shields as the one illustrated in Fig. 1...

Complete Calibration Of Pyrometers
For the complete calibration of a thermo-couple of unknown e...

Heating Of Manganese Steel
Another form of heat-treating furnace is that which is used ...

Preventing Cracks In Hardening
The blacksmith in the small shop, where equipment is usually ...

Ebbw Vale And The Bessemer Process
After his British Association address in August 1856, Besseme...

Application Of Liberty Engine Materials To The Automotive Industry
The success of the Liberty engine program was an engineer...

Mushet And Bessemer
That Mushet was "used" by Ebbw Vale against Bessemer is, perh...

Oil-hardening Steel
Heat slowly and uniformly to 1,450 deg.F. and forge thorough...

Manganese
MANGANESE is a metal much like iron. Its chemical symbol is M...

Composition And Properties Of Steel
It is a remarkable fact that one can look through a dozen tex...

Case-hardening Treatments For Various Steels
Plain water, salt water and linseed oil are the three most co...

Nickel-chromium
A combination of the characteristics of nickel and the charac...

Open Hearth Process
The open hearth furnace consists of a big brick room with a l...

Carbon-steel Forgings
Low-stressed, carbon-steel forgings include such parts as car...

Calibration Of Pyrometer With Common Salt
An easy and convenient method for standardization and one whi...

Annealing
There is no mystery or secret about the proper annealing of d...

Furnace Data
In order to give definite information concerning furnaces, fu...

Shrinking And Enlarging Work
Steel can be shrunk or enlarged by proper heating and cooling...

A Satisfactory Luting Mixture
A mixture of fireclay and sand will be found very satisfactor...

Tensile Properties
Strength of a metal is usually expressed in the number of pou...



Quenching






Category: CASE-HARDENING OR SURFACE-CARBURIZING

It is considered good practice to quench alloy steels from the pot,
especially if the case is of any appreciable depth. The texture
of carbon steel will be weakened by the prolonged high heat of
carburizing, so that if we need a tough core, we must reheat it
above its critical range, which is about 1,600 deg.F. for soft steel,
but lower for manganese and nickel steels. Quenching is done in
either water, oil, or air, depending upon the results desired.
The steel is then very carefully reheated to refine the case, the
temperature varying from 1,350 to 1,450 deg.F., depending on whether
the material is an alloy or a simple steel, and quenched in either
water or oil.



There are many possibilities yet to be developed with the carburizing
of alloy steels, which can produce a very tough, tenacious austenitic
case which becomes hard on cooling in air, and still retains a
soft, pearlitic core. An austenitic case is not necessarily file
hard, but has a very great resistance to abrasive wear.

The more carbon a steel has to begin with the more slowly will it
absorb carbon and the lower the temperature required. Low-carbon
steel of from 15 to 20 points is generally used and the carbon
brought up to 80 or 85 points. Tool steels may be carbonized as
high as 250 points.

In addition to the carburizing materials given, a mixture of 40
per cent of barium carbonate and 60 per cent charcoal gives much
faster penetration than charcoal, bone or leather. The penetration
of this mixture on ordinary low-carbon steel is shown in Fig. 32,
over a range of from 2 to 12 hr.





Next: Effect Of Different Carburizing Material

Previous: Carburizing Material



Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK


Viewed 4316