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: Aluminium Arsenic Bismuth Cadmium Cobalt Chromium Copper Iron Magnesium Manganese Molybdenum Niobium Nickel 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 SteelNews_290514_Final