ASTM B – Designation: B – 98 (Reapproved ) UNCONTROLLED (if printed out) Standar. Basic Description: ASTM B X-Ray Fluorescence (XRF) is a non-destructive method of measuring plating thickness by using an X-ray beam to excite the. Designation: B − 98 (Reapproved ) Standard Test Method for This test method is under the jurisdiction of ASTM Committee B08 on Metallic.
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The advantages of radioisotope excitation include more compact instrumentation essentially monochromatic radiation, and very low background intensity. To understand the signi? At coating thicknesses greater than approximately 10? This industry standard ASTM B should be reviewed by all operators of x-ray fluorescence because it offers a beneficial overview and highlights proper implementation of the technology.
If the coating on the standard is gold, but not electroplated under conditions known to be the same as the coating being measured, the X-ray properties may be assumed to be the astj for mass per unit qstm measurements. Last previous edition approved in as B — The stated mass per unit area of b658 coating thickness SRM is certi?
This is on the order of 35 to 50 kV for most thickness-measurement applications.
The emission now being measured comes from the substrate. A superscript epsilon e indicates an editorial change since the last revision or reapproval. Thus, would give a standard deviation indicating 10 times the precision one-tenth the standard deviation obtained from counts. Factors Affecting Accuracy 6.
Results are reported in a table satm five or more readings per sample. Suitable means must be provided to perfectly align the test specimen relative to the excitation beam. The X-ray absorption method cannot be used when one or more intermediate coating layers are present. Standards representing various thickness ranges of a number of coatings on different substrates are generally available from thickness gage manufacturers.
ASTM B X-Ray Fluorescence XRF is a non-destructive method of measuring plating thickness by using an X-ray beam to excite the surface of a sample and then calculating the intensity of the energy returned by the plating versus the base material. A minimum area of 0.
ASTM B (measurement of coating thickness by XRF) | Eastern Applied Research, Inc.
This is because both the exciting and secondary characteristic radiations undergo attenuation in passing through the coating. The intensity of the emitted secondary X radiation depends, in general, upon the excitation energy, the atomic numbers of the coating and substrate, the area of the specimen exposed to the primary radiation, the power of the X-ray tube, and the thickness of the coating.
This method can be used when the energies of the detected characteristic radiations do not differ sufficiently b658 example, characteristic radiation from Au and Br.
Calibration standards asrm gold coatings, certi? The major disadvantage of radioisotope excitation is the much lower intensities available as compared with X-ray tube sources. It is important to note that ASTM B does not detail safety procedures relating to operation of x-ray spectrometry and refers the reader to the appropriate governing bodies and regulations.
It must be established experimentally that the minimum thickness requirements have been met for a particular substrate-source combination, although it is sometimes possible to back up the test specimen substrates with a sufficient thickness of materials of the same composition. From six to sixty adjacent channels can be used to store the pulses representing a selected characteristic emission of one element, the number of channels depending on the width of the emission peak usually displayed on the face of a cathode ray tube.
Most modern industrial X-ray instrumentation will perform this calculation automatically. An increase in plating thickness results in a larger peak from the plating material and a smaller peak from the base material. If pores or voids are present, X-ray methods will give an indication of coating mass per unit area but not of thickness.
ASTM B568 (measurement of coating thickness by XRF)
Avoid specimen areas having visible defects such as? Eastern Applied Research, Inc. Published data in tabular form are available that relate spectrogoniometer settings to the characteristic emissions of elements for each of the commonly used analyzing crystals.
Calibrate it in accordance with Section 7. When an energy-dispersive system is being used it should be recognized that a signi?