Commercial X-Ray Instrument Manufacturers

Commercial XRF systems include WDXRF and EDXRF laboratory-based instruments from floor models to benchtop systems, handheld X-ray analyzers based on EDXRF, field-portable XRF systems, andmicro-XRF systems. Commercial XRD systems include single-crystal diffractometers. 

1 Take several metal disks made of different pure elements, each about 1 in. in area and 1/8 in. in thickness. It is important that the thickness of each disk be constant. The disks should be made from (a) Mg, (b) Al, (c) Fe, (d) Ni, (e) Cu, (f) Sn, and (g) Pb. Expose than to an X-ray beam simultaneously on a single sheet of X-ray photographic film. Develop this film. Note that the absorption of X-rays by each disk is proportional to the atomic weight of the particular elonent. 

2 Take a piece of glass known to contain an entrapped bubble of air. Place it in front of X-ray film and expose it to X-rays. Note that the bubble can be detected on the film as a dark patch. Similar holes in metal castings (or other metal objects) can be detected by XRA, even though the holes are not visible to the naked eye. 

3 Using the metal disks used in Experiment 8.1, record the fluorescence spectra of the diffaent metals. Identify the K and L lines for each element. Plot the relationship between the wavelengths of these lines and the atomic numbers of the metals using a spreadsheet program such as Excel. Explain your results. 

4 Record the fluorescence spectrum of metal disks of unknown composition. By measuring the wavelength of the K line, identify the major components. Use disks of brass, bronze, stainless steel, and aluminum and coins of various denominations, for example. 

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