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Important Facts on
Stainless Steel
Important Elements utilized in Steel Alloys
Aluminium (Al) Melting point 658° C
This is the most powerful, very frequently used deoxidizing and also detriding
agent. As a result, it also has an extremely favourable effect on resistance to
ageing.Small additions assist fine-grained structure. As Al forms very hard
Nitrides with Nitrogen, it is usually an alloying element in nitriding steels. It
increases scaling resistance and is therefore frequently added to alloy ferritic
heat resistance steels. With unalloyed Carbon steels, scaling resistance can
be promoted by calorizing (introduction of Aluminium into the surface). Al
very sharply restricts the Gamma phase. On account of the very pronounced
increase in coercive field intensity, Al is an alloying element in Iron-Nickel-
Cobalt-Aluminium permanent magnet alloys.
Lead (Pb) Melting point 327.4° C
Is added to free-cutting steels in contents of about 0.2-0.5% as, by virtue of
ist extremely fine suspension-like distribution, formation of shorter chips and
clean faces of cut are achieved, thus improving machinability. The lead contents
stated hardly affect the mechanical properties of the steels at all.
Boron (B) Melting point 2300° C
As Boron possesses a high cross section for neutron absorption, it is used
to alloy steels for controllers and shields of atomic energy plants. Austenitic
18/8 CrNi steels can be raised to increased yield point and strength with
boron by means of precipitation hardening, but corrosion resistance is reduced
in the process. Precipitation induced by Boron increases the strength
properties of high-temperature austenitic steel types in the high temperature
range. In structural steels, this element though hardening and thus causes
an increase in core strength in case-hardening steels. A reduction in weldability
must be expected in Boron alloyed steels.
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