a – after chemical etching (×500), b – polished sample (×100), c –SEM in secondary electrons
Figure 2.1. Typical bronze BrA9Zh3L microstructure
Source: investigated by the authors
Microstructures in Figures 2.1,b,c show that iron affects not only the change in
kinetics of structure formation. In addition to the main structural components Figure
2.1,b,c represent branched star-like small crystals, presumably, iron-containing phase.
According to [21] this phase is Fe
3
Al. But, given the fact that there is a small amount
of iron in alloy, authors [22] believe that this phase is FeAl
3
. Solving this controversy
was one of existing work tasks.
According to our own microstructural studies (see Figure 2.1,b,c), it is obvious
that this phase is placed uniformly over the sample intersection, regardless of character
of structural components distribution. Such character of iron-containing phase crystals
location indicates its primary crystallization behavior and neutral nature of influence
on system’s phase transformations during casting product structure formation.
Example of bronze BrA9Zh3L X-ray spectral microanalysis typical protocol is
presented, including characteristic radiations, in Figure 2.2. Figure 2.2 analyses
demonstrate that copper, naturally, shows a signal that is maximally uniform across the
surface of the sample.
a
b
c
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