Information depth in backscattered electron microscopy of nanoparticles within a solid matrix

Journal Article · Sun Apr 15 04:00:00 EDT 2018 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2018.01.049· OSTI ID:22804938

Österreicher, Johannes A. ^[1]; Grabner, Florian ^[1]; Schiffl, Andreas ^[2]; Schwarz, Sabine

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1. LKR Light Metals Technologies Ranshofen, Austrian Institute of Technology, Postfach 26, Ranshofen 5282 (Austria)
2. Hammerer Aluminium Industries Extrusion GmbH, Lamprechtshausener Strasse 69, Ranshofen 5282 (Austria)

Highlights: • Backscattered electron microscopy was used for reliable determination of nanoparticle density and sizes within Al alloys • Backscattered electron information depth was determined as a function of nanoparticle size from Monte Carlo simulations • Unlike transmission electron microscopy, the method is non-destructive and allows analyzing large sample areas • Good agreement with transmission electron microscopy data shows that our method is suitable for nanocomposite materials - Abstract: Measuring the dimensions and number density of nanoparticles dispersed in a solid matrix is usually accomplished via transmission electron microscopy (TEM) which suffers from high cost, low throughput, and small analytical volume. In comparison, scanning backscattered electron microscopy is inexpensive, requires little sample preparation, and allows for the analysis of large sample areas. However, the information depth is usually not known precisely and depends on several factors such as the composition of the nanoparticles and the matrix as well as the size of the nanoparticles, hindering the reconstruction of the actual size distribution and three-dimensional number density. Here we present a method to estimate the information depth for spherical nanoparticles of different sizes in order to accurately determine size distribution and number density. The approach is based on Monte Carlo simulation of electron trajectories in the material and analysis of the obtained backscattered electron signal-to-noise-ratio. Our experimental results are compared to those obtained via TEM and good agreement is demonstrated; this shows that TEM can be replaced by scanning electron microscopy for studying nanocomposites in many cases.

• OSTI ID: 22804938
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 138; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ALUMINIUM ALLOYS
COMPUTERIZED SIMULATION
DISTRIBUTION
MICROSTRUCTURE
MONTE CARLO METHOD
NANOCOMPOSITES
NANOPARTICLES
SCANNING ELECTRON MICROSCOPY
TRANSMISSION ELECTRON MICROSCOPY