2013年3月1日 · In this study, we describe a methodology to examine dislocation loops in irradiated steels based on a combination of crystallographic information and g ⋅ b invisibility criteria. Dislocation loops in transmission electron microscope (TEM) images can be conveniently analyzed using this method.

Unit cell is the smallest repeating unit of the crystal lattice! Has a lattice point on each corner (and perhaps more elsewhere) Defined by lattice parameters a, b, c along axes x, y, z and angles between crystallographic axes: α = b^c; β = a^c; γ = a^b. Centre of symmetry or!

High resolution TEM images of the σ and BCC phases in the AlCoCrFe2.7NiMo coating. (a) shows σ phase; (b) shows BCC phase. [...] High-entropy AlxCoCrFe2.7MoNi (x = 0, 0.5, 1.0, 1.5, 2.0)...

2020年5月19日 · Here, by conducting in situ transmission electron microscopy (TEM) at atomic scale, we discover that, in stark contrast to those in most Fcc metals, a majority of...

L12 and BCC dual-coherent phases precipitate from the FCC/B2 eutectics of Ni44Co10Cr12Fe15Al17W2, leading to an excellent yield strength of 805 ± 45 MPa with uniform elongation of 17.7 ± 0.9 pct...

2010年11月25日 · The anomalous-slip behavior of bcc metals has been studied by TEM analyses of dislocation substructures developed in a [2 ¯ 9 20]-oriented Mo single crystal uniaxially compressed at room temperature to a total-strain of 0.4%.

2024年9月19日 · The TEM images with corresponding SAED patterns showing (a) fcc phase in the un-SPCBNTed matrix and (b-c) hcp laths formed at ∼40 µm and ∼20 µm depth, respectively. (d) bright-field and (e) dark-field TEM images at the topmost surface layer. (f) An atomic Fourier-filtered image showing the nanoscale hcp laths with dense stacking faults.

2022年1月1日 · In situ TEM straining experiments performed on high-purity tungsten containing only 1 appm of carbon reveal the reappearance of a lattice friction opposing glide of screw dislocations above 1373 K, at temperatures high enough to activate carbon diffusion and to enable segregation of carbon atoms in the core of screw dislocation, as predicted by ...

Figure 3916a shows the standard indexed diffraction patterns for bcc crystals. The ratios of the principal spot spacings are shown as well as the angles between the principle plane normals. Forbidden refelections are indicated in red.

temperature BCC/B2 phase field into close-packed orthorhombic or hexagonal phase fields. These predictions were based on structural and symmetry rela- tions between the known phases. In the present paper experimental TEM re- sults show that two of the predicted transformation paths are indeed fol- lowed for different alloy compositions.