Steelmaking.ca Home Steel Making Categories Manufacturing and the Economy of Machinery

Steel Making

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

Connecting Rods
The material used for all connecting rods on the Liberty engi...

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

Detrimental Elements
Sulphur and phosphorus are two elements known to be detrimen...

Liberty Motor Connecting Rods
The requirements for materials for the Liberty motor connecti...

Lathe And Planer Tools
FORGING.--Gently warm the steel to remove any chill, is parti...

The Thermo-couple
With the application of the thermo-couple, the measurement of...

Brown Automatic Signaling Pyrometer
In large heat-treating plants it has been customary to mainta...

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

Chrome-nickel Steel
Forging heat of chrome-nickel steel depends very largely on ...

Crucible Steel
Crucible steel is still made by melting material in a clay or...

The Penetration Of Carbon
Carburized mild steel is used to a great extent in the manufa...

High-carbon Machinery Steel
The carbon content of this steel is above 30 points and is ha...

Pyrometers For Molten Metal
Pyrometers for molten metal are connected to portable thermoc...

Quenching Tool Steel
To secure proper hardness, the cooling of quenching of steel ...

Placing The Thermo-couples
The following illustrations from the Taylor Instrument Compan...

Hardening Carbon Steel For Tools
For years the toolmaker had full sway in regard to make of st...

Hardening
Steel is hardened by quenching from above the upper critical....

Knowing What Takes Place
How are we to know if we have given a piece of steel the ver...

Heating
Although it is possible to work steels cold, to an extent de...



Introduction Of Carbon






Category: CASE-HARDENING OR SURFACE-CARBURIZING

The matter to which these notes are primarily directed is the
introduction of carbon into the case of the article to be hardened.
In the first place the chances of success are increased by selecting
as few brands of steel as practicable to cover the requirements of
each component of the mechanism. The hardener is then able to become
accustomed to the characteristics of that particular material, and
after determining the most suitable treatment for it no further
experimenting beyond the usual check-test pieces is necessary.

Although a certain make of material may vary in composition from
time to time the products of a manufacturer of good steel can be
generally relied upon, and it is better to deal directly with him
than with others.

In most cases the case-hardening steels can be chosen from the
following: (1) Case-hardening mild steel of 0.20 per cent carbon;
(2) case-hardening 3-1/2 per cent nickel steel; (3) case-hardening
nickel-chromium steel; (4) case-hardening chromium vanadium. After
having chosen a suitable steel it is best to have the sample analyzed
by reliable chemists and also to have test pieces machined and pulled.

To prepare samples for analysis place a sheet of paper on the table
of a drilling machine, and with a 3/8-in. diameter drill, machine
a few holes about 3/8 in. deep in various parts of the sample bar,
collecting about 3 oz. of fine drillings free from dust. This can be
placed in a bottle and dispatched to the laboratory with instructions
to search for carbon, silicon, manganese, sulphur, phosphorus and
alloys. The results of the different tests should be carefully
tabulated, and as there would most probably be some variation an
average should be made as a fair basis of each element present,
and the following tables may be used with confidence when deciding
if the material is reliable enough to be used.

TABLE 16.--CASE-HARDENING MILD STEEL OF 0.20 PER CENT CARBON

Carbon 0.15 to 0.25 per cent
Silicon Not over 0.20 per cent
Manganese 0.30 to 0.60 per cent
Sulphur Not over 0.04 per cent
Phosphorus Not over 0.04 per cent

A tension test should register at least 60,000 lb. per square inch.

TABLE 17.--CASE-HARDENING 3-1/2 PER CENT NICKEL STEEL

Carbon 0.12 to 0.20 per cent
Manganese 0.65 per cent
Sulphur Not over 0.045 per cent
Phosphorus Not over 0.04 per cent
Nickel 3.25 to 3.75 per cent

TABLE 18.--CASE-HARDENING NICKEL CHROMIUM STEEL

Carbon 0.15 to 0.25 per cent
Manganese 0.50 to 0.80 per cent
Sulphur Not over 0.045 per cent
Phosphorus Not over 0.04 per cent
Nickel 1 to 1.5 per cent
Chromium 0.45 to 0.75 per cent

TABLE 19.--CASE-HARDENING CHROMIUM VANADIUM STEEL

Carbon Not over 0.25 per cent
Manganese 0.50 to 0.85 per cent
Sulphur Not over 0.04 per cent
Phosphorus Not over 0.04 per cent
Chromium 0.80 to 1.10 per cent
Vanadium Not less than 0.15 per cent

Having determined what is required we now proceed to inquire into
the question of carburizing, which is of vital importance.





Next: Using Illuminating Gas

Previous: The Penetration Of Carbon



Add to Informational Site Network
Report
Privacy
ADD TO EBOOK


Viewed 5036