Stainless Steel Testing

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Steel Testing
What is Steel?
Steel is an alloy of the transition metal iron and a combination of other chemical
elements, including the non-metal carbon. The composition of steel, through the addition
of other elements, determines the physical properties of the alloy including malleability,
tensile strength, ductility and hardness. There are specific elements that are consistently
present in steel; these include carbon, silicon, manganese, sulphur and phosphorus with
traces of oxygen, nitrogen and aluminium. Elements added during manufacture to obtain
specific physical properties include aluminium, arsenic, manganese, chromium, nickel,
boron, titanium, niobium, molybdenum, vanadium, zirconium, lead, cobalt and others.
There can also be elemental impurities present within the steel.
Why Do We Need to Test Steel?
The use of metals, especially iron, can be traced globally throughout mankind’s history
for thousands of years. To reach many major milestones in industrial and economic
progression we relied on metals to improve and implement key developments. Steel is a
material of significance in our historical progression as it plays a key role in our day to
day lives. Examples include transportation, including railways and cars, housing and
construction, wind turbines and electricity pylons for power generation and deliverance
and steel cans to increase the lifespan of foods. With many diverse applications steel is a
vital material in many industries and due to its importance it should be tested for
suitability for its particular application.
The mechanical properties of steel can be meticulously controlled by the selection of
elements contained within its structure.
Steel is ‘graded’ based on the chemical
composition, manufacturing methods, finishing processes, deoxidation practice (i.e.
capped or rimmed etc.), the form it takes (i.e. tubing, sheet etc.), heat treatment,
microstructure, required strength level and carbon content (low, middle and high). In
addition to these general distinguishments, European classification grades steel into
further categories including non-alloy steel grades, alloy steel grades, steel grades for
electrical sheet and strip, steel grades for sheet and strip, tool steel grades and stainless
steel grades.
The chemical analysis of steel determines qualitatively the elements present within the
alloy and quantifies the level of each element present. This ensures that the correct
grading can be used for the desired application. This can provide optimum assurance of
the grade of steel in question and additionally identify any anomalies, such as impurities
present or incorrect grading.
How is the Composition of Steel Determined?
Sheffield Analytical Services, a part of the Sheffield Assay Office, have a selection of
specialist equipment and expertise which ensures reliable analysis and turnaround times
to suit you. ICP-OES (Inductively Coupled Plasma – Optical Emission Spectroscopy) is
our preferred method to determine the chemical composition of steel samples. ICP-OES
offers both rapid analysis and inherent accuracy and is widely used within the metal
making industries as part of their Due Diligence and Quality Control.
This analytical technique quantitatively measures the elemental content of your steel
sample. Firstly your steel sample is dissolved into an acidic aqueous solution, the sample
is then sprayed into a core of inductively coupled argon plasma, which can be up to a
temperature of 8000°C. At these temperatures the components of the sample are
atomised, ionised and thermally excited and then detected and quantified by OES.
What Elements can the Sheffield Assay Office standard elemental analysis via
ICP-OES, Nitrogen and Oxygen by IR combustion and Carbon and sulphur?
Sheffield Assay Office provide qualitative and quantitative analysis of steel that detects
the following elements:
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Aluminium
Arsenic
Bismuth
Cadmium
Cobalt
Chromium
Copper
Iron
Magnesium
Manganese
Molybdenum
Niobium
Nickel
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Phosphorus
Lead
Antimony
Selenium
Silicon
Tin
Tantalum
Titanium
Vanadium
Tungsten
Zinc
Zirconium
Analytical Services can also provide trace analysis for specific element including carbon,
sulphur, nitrogen and others. Further details are available upon request.
Should you have any further questions relating to steel testing, please do not
hesitate to contact us. We would be happy to discuss this with you.
Sheffield Assay Office:
UK: 0114 2312121 International: +44114 2312121
Web: www.assayoffice.co.uk Email: analytical@assayoffice.co.uk
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