scholarly journals Automated Multi-Scale Microstructure Heterogeneity Analysis of Selective Electron Beam Melted TiA16V4 Components

2015 ◽  
pp. 429-436
Author(s):  
H Zhao ◽  
A. A. Antonysamy ◽  
J. Meyer ◽  
O. Ciuea ◽  
S. T. Williams ◽  
...  
Author(s):  
H Zhao ◽  
A. A. Antonysamy ◽  
J. Meyer ◽  
O. Ciuca ◽  
S. T. Williams ◽  
...  

2021 ◽  
pp. 2100257
Author(s):  
Hiroki Miyazako ◽  
Kunihiko Mabuchi ◽  
Takayuki Hoshino

2013 ◽  
Vol 4 ◽  
pp. 781-792 ◽  
Author(s):  
Francesc Salvat-Pujol ◽  
Harald O Jeschke ◽  
Roser Valentí

We present a numerical investigation of energy and charge distributions during electron-beam-induced growth of tungsten nanostructures on SiO2 substrates by using a Monte Carlo simulation of the electron transport. This study gives a quantitative insight into the deposition of energy and charge in the substrate and in the already existing metallic nanostructures in the presence of the electron beam. We analyze electron trajectories, inelastic mean free paths, and the distribution of backscattered electrons in different compositions and at different depths of the deposit. We find that, while in the early stages of the nanostructure growth a significant fraction of electron trajectories still interacts with the substrate, when the nanostructure becomes thicker the transport takes place almost exclusively in the nanostructure. In particular, a larger deposit density leads to enhanced electron backscattering. This work shows how mesoscopic radiation-transport techniques can contribute to a model that addresses the multi-scale nature of the electron-beam-induced deposition (EBID) process. Furthermore, similar simulations can help to understand the role that is played by backscattered electrons and emitted secondary electrons in the change of structural properties of nanostructured materials during post-growth electron-beam treatments.


2021 ◽  
Vol 8 (18) ◽  
pp. 2170101
Author(s):  
Hiroki Miyazako ◽  
Kunihiko Mabuchi ◽  
Takayuki Hoshino

2016 ◽  
Vol 115 ◽  
pp. 403-412 ◽  
Author(s):  
Wentao Yan ◽  
Wenjun Ge ◽  
Jacob Smith ◽  
Stephen Lin ◽  
Orion L. Kafka ◽  
...  

Author(s):  
G. G. Shaw

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.


Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.


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