IPT01 ALLOYING ELEMENTS IN STEEL Last Revised: May 2015 1. PURPOSE This exercise analyses the three major alloying elements found in many steels: nickel, chromium and manganese by ICP analysis. 2. REAGENTS & EQUIPMENT 2.1 1000 mg/L Cr, Ni & Mn standards 2.2 Steel samples EN36A, 8660, EN25, 4140, 8115, 8620 2.3 5 M nitric acid 3. PROCEDURE 3A. Prework – you should do this before class 3.1 You will be assigned a steel sample by its internationally recognised composition code. 3.2 Look up its Ni, Cr & Mn composition (as ranges). Hint: use the code and the word steel as search terms in Google). 3.3 Determine an appropriate sample mass that ensures all three analytes are within the concentration range 5‐50 mg/L, based on a final volume of either 100 or 250 mL. Hint: 1 g of 1%w/w in 100 mL is 100 mg/L. 3.4 Devise a dilution scheme to prepare 5, 20 and 50 mg/L mixed standards of the three analytes, starting from the 1000 mg/L solutions. Hint: make a mixed intermediate standard to prepare the three calibration standards from. 3B. Sample & standard preparation 3.5 Weigh accurately in triplicate, the sample mass calculated in Prework. 3.6 Transfer to 150 mL beakers and add 25 mL of 5 M HNO3 to each. 3.7 Place a watchglass over each and boil gently until brown fumes has ceased. Do not boil to dryness! 3.8 Add 25 mL of water to each and cool in an icebath. 3.9 Transfer to volumetric flasks as determined in Prework and make up to the mark with distilled water. 3.10 Filter by Millepore for analysis. 3.11 Prepare the standards as per Prework. 3C. Analysis 3.12 Run each of the solutions on the ICP and record the intensities of each element. Reporting 
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Enter the data into the spreadsheet found on the subject website. Transfer the final results – average %w/w and relative precision for each element – to your Result Sheet and submit this.