ASTM E1409-13(R2021) pdf free download

ASTM E1409-13(R2021) pdf free download.Standard Test Method for Determination of Oxygen and Nitrogen in Titanium and Titanium Alloys by Inert Gas Fusion
4. Summary of Test Method
4.1 This test method is intended for use with automated, commercially available, inert gas fusion analyzers. These analyzers typically measure both oxygen and nitrogen simul- taneously or sequentially utilizing parallel measurement sys- tems. 4.2 The test sample, plus flux, is fused in a graphite crucible under a flowing inert gas stream at a temperature sufficient to release oxygen and nitrogen. Oxygen combines with carbon to form carbon monoxide (CO) and nitrogen is released as N 2 . Depending on instrument design, the CO may be oxidized to carbon dioxide (CO 2 ). The CO or CO 2 , or both, are swept by the inert gas stream into either an infrared or thermal conduc- tivity detector. The detector response generated by analysis of the test sample is compared to the response generated by analysis of reference materials and the result is displayed as percent oxygen. The nitrogen is swept by the inert gas stream into a thermal conductivity detector. The detector response generated by analysis of the test sample is compared to the response generated by analysis of reference materials and the result is displayed as percent nitrogen. 4.3 In a typical instrument for the determination ofnitrogen, the sample gases are swept with inert gas through heated rare earth/copper oxide that converts CO to CO 2 and hydrogen (H 2 ) to water (H 2 O). The CO 2 is absorbed on sodium hydroxide impregnated on clay, and the H 2 O is removed with magnesium perchlorate. The nitrogen, as N 2 , enters the measuring cell and the thermistor bridge output is integrated and processed to display percent nitrogen.
8. Reagents
8.1 Acetone—Low residue reagent grade or higher purity. 8.2 Graphite Powder (optional)—High-purity as specified by the instrument manufacturer. 8.3 Inert Gas—Use the purity and type specified by the instrument manufacturer. 8.4 Magnesium Perchlorate, Anhydrous 4 —Used in the in- strument to absorb water. Use the purity specified by the instrument manufacturer. 8.5 Nickel Flux Cleaning Solution—An acid solution ca- pable of removing surface contamination from the nickel flux. A solution made by combining 75 mL of acetic acid, 25 mL of HNO 3 , and 2 mL of HCl has been found suitable for this purpose. 8.6 Copper Oxide or Rare Earth/Copper Oxide—Reagent used in some instruments to oxidize CO to CO 2 for detection. Use the purity specified by the instrument manufacturer. 8.7 Sodium Hydroxide on Clay 5 —Reagent used in some instruments to absorb CO 2 . Use a purity specified by the instrument manufacturer. 8.8 Titanium Sample Pickle Solution—Three parts 30 % hydrogen peroxide (H 2 O 2 ) and 1 part 48 % HF. Other pickle solutions may be substituted if there are data supporting the effectiveness of the solution on removing contaminants. For example, substituting concentrated HNO 3 for 30 % H 2 O 2 has been found effective (see Note 3). (Warning—HF causes serious burns that may not be immediately painful; refer to the paragraph about HF in the Hazards Section of Practices E50.) N OTE 3—In 2004, alternative sample preparation procedures (Section 12) were tested by seven laboratories. Three laboratories processed the sample materials by pickling their samples in HF-H 2 O 2 (8.8). Two laboratories utilized the HF-HNO 3 alternative pickle solution (8.8). Two laboratories utilized abrasion (in this case diamond saw and shear) in accordance with 12.2. The prepared samples were distributed among the laboratories for analysis. Six laboratories analyzed these samples in random order under a single operator, single-day, single calibration sample run.
10. Preparation of Apparatus
10.1 Assemble the apparatus as recommended by the manu- facturer. Make the required power, gas, and water connections. Turn on the instrument and allow sufficient time to stabilize the equipment. 10.2 Change the chemical reagents and filters as required. Test the furnace and analyzer to ensure the absence of leaks (Note 4). A minimum of two test runs using a sample as directed in 14.3 and 14.4 is recommended to condition the newly changed filters. This should be done before attempting to calibrate the system or to determine the value of the blank. N OTE 4—Typical leak checks should be 0.0 mm Hg to 1.5 mm Hg. The maximum allowable leak check should follow the manufacturer’s recom- mendation.