Sing. Plural 1st person If I had loved If we had loved 2nd person If you had loved If you had loved 3rd person If he had loved If they had loved ... Read more of PAST PERFECT TENSE at Speaking Writing.comInformational Site Network Informational
Privacy
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

Pyrometers
Armor plate makers sometimes use the copper ball or Siemens' ...

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

Quenching
It is considered good practice to quench alloy steels from th...

Care In Annealing
Not only will benefits in machining be found by careful anne...

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

Quality And Structure
The quality of high-speed steel is dependent to a very great ...

Carburizing Low-carbon Sleeves
Low-carbon sleeves are carburized and pushed on malleable-ir...

The Electric Process
The fourth method of manufacturing steel is by the electric f...

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

Manganese
Manganese adds considerably to the tensile strength of steel,...

Heat Treatment Of Punches And Dies Shears Taps Etc
HEATING.--The degree to which tools of the above classes shou...

Composition Of Transmission-gear Steel
If the nickel content of this steel is eliminated, and the pe...

The Care Of Carburizing Compounds
Of all the opportunities for practicing economy in the heat-t...

Heat Treatment Of Axles
Parts of this general type should be heat-treated to show the...

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

A Chromium-cobalt Steel
The Latrobe Steel Company make a high-speed steel without tun...

Carburizing By Gas
The process of carburizing by gas, briefly mentioned on page ...

Application To The Automotive Industry
The information given on the various parts of the Liberty eng...

The Effect
The heating at 1,600 deg.F. gives the first heat treatment w...

Restoring Overheated Steel
The effect of heat treatment on overheated steel is shown gra...



Quenching Tool Steel






Category: HARDENING CARBON STEEL FOR TOOLS

To secure proper hardness, the cooling of quenching of steel is
as important as its heating. Quenching baths vary in nature, there
being a large number of ways to cool a piece of steel in contrast
to the comparatively few ways of heating it.

Plain water, brine and oil are the three most common quenching
materials. Of these three the brine will give the most hardness,
and plain water and oil come next. The colder that any of these
baths is when the piece is put into it the harder will be the steel;
but this does not mean that it is a good plan to dip the heated
steel into a tank of ice water, for the shock would be so great
that the bar would probably fly to pieces. In fact, the quenching
bath must be sometimes heated a bit to take off the edge of the
shock.

Brine solutions will work uniformly, or give the same degree of
hardness, until they reach a temperature of 150 deg.F. above which
their grip relaxes and the metals quenched in them become softer.
Plain water holds its grip up to a temperature of approximately
100 deg.F.; but oil baths, which are used to secure a slower rate of
cooling, may be used up to 500 deg. or more. A compromise is sometimes
effected by using a bath consisting of an inch or two of oil floating
on the surface of water. As the hot steel passes through the oil,
the shock is not as severe as if it were to be thrust directly
into the water; and in addition, oil adheres to the tool and keeps
the water from direct contact with the metal.

The old idea that mercury will harden steel more than any other
quenching material has been exploded. A bath consisting of melted
cyanide of potassium is useful for heating fine engraved dies and
other articles that are required to come out free from scale. One
must always be careful to provide a hood or exhaust system to get
rid of the deadly fumes coming from the cyanide pot.

The one main thing to remember in hardening tool steel is to quench
on a rising heat. This does not mean a rapid heating as a slow
increase in temperature is much better in every way.





Next: The Theory Of Tempering

Previous: Double Annealing



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 3274