Page 35 - PR 2014 2016 10 Materials and Nanotechnology

Materials and Nanotechnology | Progress Report 311

damental characteristics, such as grain size and Development of x-ray diffraction
shape, number of neighbors, local heterogene- methodologies of materials
ities, extreme values and distribution patterns. characterization
GC allows seamless exploration of virtual grain
samples through first-person fly navigation X-ray diffraction is a fundamental phenom-
(Figure 43) on a grain-by-grain basis, evaluating enon resulting from the interaction of the
individual sizes and shapes, but also allow- photons and the atoms revealing the crystal
ing capturing structural information such as structure of the materials. This technique is
neighborhoods and heterogeneities. Interactive widely used to study the microstructure evolu-
real-time sectioning allows infinite sections to tion that takes place during various processes
be visualized continuously in a brief period and including thermomechanical processing of ma-
designed rendering techniques improve depth terials. The continuous evolution of materials
perception either on 2D scenarios (Figure 44) or development, in the scientific aspect as well
in full-fledged stereoscopic visualization, pre- as for industrial applications, also implies in
senting superior visualization value compared a continuous evolution of the methodologies
to earlier attempts. GC can be accessed online of materials characterization. The following
at http://gvcm.co/GrainCrawler/ from desktop, application was performed in the CCTM´s x-ray
mobile and tablet devices and video demos diffraction laboratory.
and its source code is available at the project
website at http://gvcm.co/en-graincrawler/. Nanomaterials:

Nanostructured coatings have been used to
protect components exposed to severe ser-
vice conditions. High energy milling is widely
used to produce nanocrystalline feedstock of
coating materials such as chromium carbide
and tungsten carbide. During the high energy
milling of Cr C –25(Ni20Cr) powder, severe
3
2
plastic deformation takes place. A small part
Figure 44: GrainCrawler screenshots demonstrating a real-time of the energy spent in this process is stored
rendering technique that enhances depth perception on 2D visual- in the crystal lattice as deformation energy.
ization. (Left) section plane of a virtual 3D polycrystalline material.
(Right) grains intercepted by the section plane were removed. The crystallite size and microstrain in nano-

Figure 43: GC screenshots, showing: (left) perspective view of a cubic grain sample in first person navigation; (center) real-time interactive
sectioning; (right) boundary enhancement rendering.