Naslov
Stability of XCT measurements with different (W, Mo, Cu, and Ag) X-ray target material

Autori
Katić, Marko ; Baršić, Gorana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, prošireni sažetak, znanstveni

Izvornik
Macroscale, Recent Developments in Traceable Dimensional Measurements, Dimensional and Related Measurements at Macroscopic Scale, Espoo, Finland, 2017 / - , 2017

Skup
Macroscale, Recent Developments in Traceable Dimensional Measurements

Mjesto i datum
Espoo, Finska, 17.10.2017. - 19.10.2017

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Computed tomography, multi-spectral CT, CT accuracy

Sažetak
X-ray computed tomography is becoming widely used for metrology of complex geometry, and special attention is given to measurement of assemblies of different materials, since they are fairly common in industrial applications. Multi-material objects are adding additional problems in CT data evaluation, which only complicates the usual issues found in single material CT (beam hardening, streak artefacts etc.). Dual-energy CT scanning is a well-known approach to resolve issues arising from samples having various densities- a sample is scanned at two distinct energy levels, creating different x-ray spectra for each scan. Using different x-ray target materials is a different way of achieving this ; emission spectrum can be changed while keeping the energy level constant. Constant energy results with a constant focal spot size over multiple scans, meaning that such multi-spectral technique should provide better detail in CT scans. One of the problems with this technique arises because, in our case, the target needs to be rotated manually between consecutive scans, which can affect magnification (by changing the position of focal spot) and consequently have adverse effect on accuracy. We investigated this by scanning a typical sample (electrical connector assembly, made of two different polymer materials) with four different target materials (Tungsten, Molybdenum, Copper and Silver, Figure 1). Energy and exposure time were kept constant (200 kV, 120 µA, 500 ms) between scans which were acquired at 0.5° increments (720 projections) using stop-and-go technique. Reconstructions were made with constant parameters to eliminate their influence on reconstructed volumes. Additionally, four repeated scans using Tungsten target were made as a control group with all scan settings equal to previous scans.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo, Interdisciplinarne tehničke znanosti

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