622. If you put on any garment wrong side out, as, for example, a pair of stockings, never change it, as to do so brings ill luck. This direction is intuitively followed by many people who are entirely free from conscious superstition. ... Read more of Dressing at Superstitions.caInformational Site Network Informational
Privacy
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

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

Effect Of A Small Amount Of Copper In Medium-carbon Steel
This shows the result of tests by C. R. Hayward and A. B. Joh...

The Packing Department
In Fig. 56 is shown the packing pots where the work is packe...

Properties Of Alloy Steels
The following table shows the percentages of carbon, manganes...

Carburizing Material
The simplest carburizing substance is charcoal. It is also th...

Correction By Zero Adjustment
Many pyrometers are supplied with a zero adjuster, by means ...

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

Bessemer Process
The bessemer process consists of charging molten pig iron int...

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

Alloying Elements
Commercial steels of even the simplest types are therefore p...

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

Gas Consumption For Carburizing
Although the advantages offered by the gas-fired furnace for ...

Heat Treatment Of Gear Blanks
This section is based on a paper read before the American Gea...

Introduction Of Carbon
The matter to which these notes are primarily directed is the...

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

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

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

Steel Can Be Worked Cold
As noted above, steel can be worked cold, as in the case of ...

Hardening High-speed Steel
In forging use coke for fuel in the forge. Heat steel slowly ...

Pyrometry And Pyrometers
A knowledge of the fundamental principles of pyrometry, or th...



Nickel-chromium






Category: ALLOYS AND THEIR EFFECT UPON STEEL

A combination of the characteristics of nickel and the characteristics
of chromium, as described, should obviously give a very excellent
steel as the nickel particularly affects the ferrite of the steel
and the chromium the carbon. From this combination, we are able to
get a very strong ferrite matrix and a very hard tough cementite.
The strength of a strictly pearlitic steel over a pure iron is due
to the pearlitic being a layer arrangement of cementite running
parallel to that of a pure iron layer in each individual grain. The
ferrite i.e., the iron is increased in strength by the resistance
offered by the cementite which is the simple iron-carbon combination
known to metallurgists as Fe3C. The cementite, although adding
to the tensile strength, is very brittle and the strength of the
pearlite is the combination of the ferrite and cementite. In the
event of the cementite being strengthened, as in the case of strictly
chromium steels, an increased tensile strength is readily obtained
without loss of ductility and if the ferrite is strengthened then
the tensile strength and ductility of the metal is still further
improved.

Nickel-chromium alloy represents one of the best combinations available
at the present time. The nickel intensifies the physical characteristics
of the chromium and the chromium has a similar effect on the nickel.

For case-hardening, nickel-chromium steels seem to give very excellent
results. The carbon is very rapidly taken up in this combination,
and for that reason is rather preferable to the straight nickel steel.

With the mutually intensifying action of chromium and nickel there
is a most suitable ratio for these two alloys, and it has been found
that roughly 2-1/2 parts of nickel to about 1 part of chromium
gives the best results. Therefore, we have the standard types of
3.5 per cent nickel with 1.5 per cent chromium to 1.5 per cent
nickel with 0.6 per cent chromium and the various intermediate
types. This ratio, however, does not give the whole story of
nickel-chromium combinations, and many surprising results have
been obtained with these alloys when other percentage combinations
have been employed.





Next: Vanadium

Previous: Chromium



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 3578