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Most customers require specific
metallurgical properties for their
castings. Typically, one of the
metallurgical properties specified is
the chemical composition of the steel .
Chemical analysis is required to
ascertain the chemical composition of a
heat of steel. Chemical testing at
Southwest Steel is done with an Optical
Emission Spectrometry. Also, when
required, Southwest Steel can provide
material certification to a specified
standard.
Southwest Steel Casting Company is, as
are most foundries, a principal recycler
of scrap metals. Scrap metal is sorted
by its known chemical properties when it
arrives at Southwest Steel. When a
‘heat’ is required with specific
chemical requirements, the scrap charge
for the arc furnace is made up of these
presorted metals.
Once the scrap has been melted in the
arc furnace, a sample is drawn and sent
to the Metallurgical Lab for chemical
analysis. Once the metallurgical
properties of the sample are determined,
a ‘recipe’ can be formulated to bring
the ‘heat’ in the arc furnace to a
particular chemical specification. This
is typically done by adding various
alloys to the furnace.
At least two more times during the
melting and pouring process, samples are
analyzed to verify the steel’s chemical
composition. The final test being done
as the heat is being poured. This is the
sample that will be the basis of
certification that is sent to the
customer.
Optical
Emission Spectrometry
Optical Emission Spectrometry (OES)
using arc and spark excitation is the
preferred method to determine the
chemical composition of metallic
samples. This process is widely used in
the metal making industries, including
primary producers, foundries, die
casters and manufacturing.
Due to its rapid analysis time and
inherent accuracy, Arc/Spark OES systems
are most effective in controlling the
processing of alloys. These
spectrometers are used in the quality
control of metal processing where a
chemical composition of the metallic
material is required. |
