ASTM E – Download as PDF File .pdf), Text File .txt) or read online. Standards. This test method is under the jurisdiction of ASTM Committee E01 on For E – 07 in Spectrochemical Analysis calculations are used to correct for both. Designation: E – 07 Standard Test Method for Analysis of Other forms may 1 This test method is under the jurisdiction of ASTM.
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Astn Standard Test Me Standard Test Method f A number in parentheses indicates the year of last reapproval. A superscript epsilon e indicates an editorial change since the last revision or reapproval. The aluminum specimen to be analyzed may be in the form of a chill cast disk, casting, foil, sheet, plate, extrusion or some other wrought form or shape.
The elements covered in the scope of this method are listed in the table below. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Current edition approved June 1, Originally approved in Last previous edition approved in as E — The range shown for each e2151-07 does not demonstrate the actual usable analytical range for that element. The usable analytical range may be extended higher or lower based on adtm instrument capability, spectral characteristics of the speci?
The corrections are accomplished mathematically and are applied to both the slope and intercept. Improved precision may ashm obtained by using a multi-point drift correction atm described in Practice E Summary of Test Method 4. The energy of the discharge is sufficient to ablate material from the surface of the sample, break the chemical or physical bonds, and cause the resulting atoms or ions to emit radiant energy.
The radiant energies of the selected analytical lines and the internal standard line s are converted into electrical signals by either photomultiplier e1251-007 PMTs or a suitable solid state detector. The detector signals are electrically integrated wstm converted to a digitized value. The signals are ratioed to the proper internal standard signal and converted into concentrations by a computer in accordance with Practice E This approach is used when there is a need to analyze almost the entire range of aluminum alloys.
Mathematical 2 calculations are used to correct for both alloy difference and inter-element effects. Like the method above, speci? Precise and accurate analyses are essential to obtaining desired properties, meeting customer speci?
What is most accurate “referee” method for composition analysis of aluminum alloys?
Also, other sample forms can be melted-down and cast into a disk, using an appropriate mold, as described in Practice E However, it should be noted that some elements for example, magnesium readily form oxides, while some others for example, sodium, lithium, calcium, and strontium are volatile, and may be lost to varying degrees during the melting process.
Recommended Analytical Lines and Potential Interferences 6. Other lines may be used if they give comparable results.
Also listed are recommended concentration range, background equivalent concentration BECdetection limit, useful linear range, and potential interferences. The values given in this table are typical; actual values obtained are dependent on instrument design. Chill cast samples, poured and cast as described within Practice E shall be the recommended form in this test method.
A variable speed cutter, a cemented carbide or polycrystalline diamond tool bit, and an automatic cross-feed are highly recommended. Proper depth of cut and desired surface? Second 2nd indicates that the second order shall be used, where available. Background Equivalent Concentration BEC —The concentration at which the signal due to the element is equal to the signal due to the background. In this test method, the calculated detection limit was measured by calculating the standard deviation of ten consecutive burns on a specimen with element concentration s at levels below ten times the expected detection limit.
D See footnote C. E High Concentration Index—The concentration at which the slope of the calibration curve drops below 0. F Interference Factor, k—The apparent increase in the concentration of the element being determined, expressed in percent, due to the presence of 1.
G Useful analytical lines with improved signal to background ratios due to the complete removal of C-N background by the argon atmosphere. H If phosphorus is to be determined, the most sensitive line appears to be the The vacuum spectrometer should be operated at a pressure of 25 microtorr or less. Optimum results are obtained by using a background channel that has been pro?
The ratio of P Even with this compensation for variability in background, alloys with highly different compositions of major alloying elements, particularly silicon, require separate reference materials and analytical curves. C duration3 an arc type discharge of some preset durationand 4 a spark-type discharge, during which, time resolved measurements are made for improved detection limits, this may be optional on some instruments. It should be emphasized that the information presented is given as an example only and parameters may vary with respect to instrument model and manufacturer.
For details on describing and specifying an excitation source, please refer to Practice E The seal that is formed between the two will exclude atmospheric oxygen from entering the discharge chamber.
The excitation chamber will contain a mounting clamp to hold the counter electrode. The excitation stand assembly will also have some type of clamp or device designed e2151-07 hold the sample? Some manufacturers may provide for the top plate to be liquid cooled to minimize sample heat-up during the excitation cycle. The excitation chamber will also be constructed so that it is?
The excitation chamber will be equipped with an exhaust system that will safely dispose of the argon gas and the metal dust created during the excitation cycle. For reasons of health and cleanliness, the exhausted gas and dust should not be vented directly into the laboratory. Satm exhaust can then be vented into an efficient hood system.
The purity of the argon gas will affect the precision of the results. Generally, precision improves as the purity of the aztm gas gets higher. Argon gas with a minimum purity of The gas shall be delivered by a?
What is most accurate “referee” method for composition analysis of aluminum alloys?
The argon gas source can be from high-purity compressed gas cylinders, a cryogenic-type cylinder that contains liquid argon or possibly from a central supply liquid only. It is essential that only argon gas meeting the minimum purity of Delivery tubing must not produce any contamination of the argon stream.
Refrigerator grade copper tubing is recommended. The gages on the regulator will allow for the adjustment of the gas pressure to the instrument. Please note that the delivery tube connections should be made with all metal seals and the delivery tubing itself should be kept as short as possible Note 3.
Argon supply shall be sufficient to support required? All connections must be leak-free. Data should be accessible asfm the operator throughout all steps of the calculation process. Concentration data may be automatically transferred to a site mainframe d1251-07 or server for further data storage and distribution. The counter electrode should be made from thoriated tungsten or silver and have a pointed end.
The gap distance between the specimen surface and the tip of the counter electrode is speci? The diameter and geometry of the counter electrode is also application and vendor dependent. The counter electrode con? Electrode maintenance frequent brushing of the counter electrode to maintain its con? It is recommended that the purchaser specify that the instrument come with asym spare counter electrodes so that they can be replaced when necessary.
These materials should also possess a metallurgical condition that is similar to the material s that are being analyzed. The calibrants shall be used to produce the analytical curves for the various elements being determined. The concentrations of these calibrants should be fairly evenly spaced over the calibrated analytical range so that a mathematically valid calibration curve can be established using all of the points. Also, there are other commercial sources for aluminum reference materials.
These reference materials can be used for establishing the analytical curve, but will not reveal potential interferences from nearby lines of other elements, or matrix effects that change instrument response or background.
For optimum usefulness, several of the calibrants should have concentrations for the other elements that vary over the expected ranges in the specimen to be analyzed. NOTE 4—Atomic emission analysis is a comparative technique that requires a close match of the metallurgy, structure and composition between the reference material and the test material.
Differences in structure, such as result from the sodium modi? To ensure analytical accuracy, care must be taken to match the characteristics of the reference material to that of the test material or suitable corrections to adjust for these in?
The low standardant is usually high purity smelter grade aluminum. The high standardant s should have concentrations near or above the median concentration for the calibrated range of each spectral line. The commercially available standardants are tested for homogeneity and reproducibility of spectral response but are not necessarily certi?
Care should be exercised when replacing depleted standardants with new ones that are from different heats or lots since the actual concentration of the individual element s may be different from the standardant currently in use.
Whenever standardants are replaced, appropriate procedures must be followed to reference the e12510-7 obtained from the new standardant to the intensities obtained from the standardant being replaced. These materials are used to establish the background readings of the spectrometer for most elements. Their exact compositions need not be known. They may be used e125-07 the lowest concentration of the element being determined is within ten times the detection limit of that element. These materials are certi?
This correction is then applied to each subsequent analysis. When using this approach it is assumed that the composition s of the unknown s will be essentially similar to the composition of the e12251-07 standardant. The instrument should be designed so access to the power supply is restricted by the use of safety interlocks.
Therefore, the instrument shall be designed with an internal exhaust system that is equipped with its own set of? Additionally, the instrument exhaust atm being? To keep the instrument running properly, the?