A TEM study of the crystallography of lath-shaped austenite precipitates in a duplex stainless steel

Du, Juan; Mompiou, Frédéric; Zhang, Wenzheng

doi:10.1007/s10853-017-1324-y

Cited by 13 publications

(4 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When the product phase forms near a surface or in a thin foil such as in a TEM sample, the product phase tends to grow along an invariant line, lying in the surface. This result was reported early by Dahmen and Westmacott [54], and was confirmed repeatedly in investigations by the author's group [80,81]. The constraint of the direction of the invariant line does not fix the OR, but with the O-line condition, the OR is fixed.…”

Section: Irrational Orsupporting

confidence: 75%

“…The constraint of the direction of the invariant line does not fix the OR, but with the O-line condition, the OR is fixed. Some O-line interfaces are indeed observed from precipitates on the surface [81], but the selection of other ORs might be affected by different factors [80]. In general, the invariant-line directions together with the ORs vary widely with the random surface of the grains of the parent phase.…”

Section: Irrational Ormentioning

confidence: 99%

See 1 more Smart Citation

Reproducible Orientation Relationships Developed from Phase Transformations—Role of Interfaces

Zhang

2020

Crystals

View full text Add to dashboard Cite

The orientation relationship (OR) between phases related by a phase transformation is often reproducible. This study interprets and predicts the reproducible ORs with a two-stage approach. The initial OR formed at the nucleation stage tends to allow a periodic structure of a preferred state to form in the interface. A matching correspondence of either a one-to-one or n-to-m nature can be specified in the periodic structure. An initial OR will become the final reproducible OR if there is no misfit. Otherwise, a reproducible OR developed at the growth stage tends to permit a singular dislocation structure to form in an interface where the preferred state must be sustained locally. The actual change in the OR is subject to the given material system and the phase-transformation condition. Various singular dislocation structures and their constraints on the ORs are analyzed, with thermodynamics and kinetics applied conceptually. The resulting ORs can be specified by following one or more Δg parallelism rules. A set of workable steps is provided to facilitate the interpretation of observed reproducible ORs. Some unsolved problems are identified, which call for further studies that can quantitatively combine the thermodynamics, kinetics and crystallography of phase transformations.

show abstract

Section: Irrational Orsupporting

confidence: 75%

Section: Irrational Ormentioning

confidence: 99%

Reproducible Orientation Relationships Developed from Phase Transformations—Role of Interfaces

Zhang

2020

Crystals

View full text Add to dashboard Cite

show abstract

“…As a consequence, from the perspective of microstructural design and optimization, the prismatic precipitate plates with a large aspect ratio are invariably built purposefully in the microstructure. Here, it is necessary to point out that the nucleation, growth, and final shapes of precipitates are substantially influenced by many factors. − In the continuous precipitation process, for example, the nucleation of the precipitate is controlled by its precursor phase and involves the similarity of crystallographic planes between new and parent phases. , In comparison, the growth directions and final shapes of precipitates are dependent more on their crystallographic orientations and interfacial matching relationships with the α-Mg matrix. − Thus, it is of great significance to understand comprehensively the crystallographic orientations of precipitates for the reasonable construction of effective precipitation strengthening phases.…”

Section: Introductionmentioning

confidence: 99%

On Shapes and Orientations of Precipitation Strengthening Phases in an Aged Mg–La Alloy

Sun

Ren

Wang

et al. 2023

Crystal Growth & Design

View full text Add to dashboard Cite

The shapes and orientations of precipitates have important influences on the mechanical properties of precipitation-strengthened magnesium alloys. In this work, the microstructure and precipitation behaviors of an aged Mg-3.0 wt % La alloy are investigated by atomic resolution scanning transmission electron microscopy. The main precipitate product at the peak-aged stage is a category of La-enriched solid solution with a face-centered cubic (FCC) lattice, which will subsequently evolve into another precipitation strengthening phase with a tetragonal (T) lattice at the over-aged stage. The crystallographic orientations and shapes of FCC and T precipitates are elaborated on. Distinctively, La-rich FCC structures can maintain three types of orientation relationships (ORs) with the α-Mg matrix, which are defined as type-A OR (⟨001⟩FCC //[0001]α), type-B OR (⟨110⟩FCC //[0001]α), and type-C OR (⟨111⟩FCC //[0001]α). It is concluded that the T phase always nucleates at the {100}FCC crystallographic planes of La-rich FCC structures and gradually grows up by consuming La-rich solid solution. Based on the conversion from FCC to T lattices, the occurred T precipitates can be divided into four classifications whose fourfold rotational axes are parallel to the c-axis, basal plane, ⟨202̅3⟩α, and ⟨101̅2⟩α zone axes of the α-Mg matrix, respectively. At the same time, there exist six sets of crystallographic ORs (type-A1, type-A2, type-A3, type-B1, type-B2, and type-C1) between the T phase and α-Mg matrix. In view of the interfacial matching, the shapes of the existing T phase involve the sphere, prismatic, and basal plates, whose effects on the mechanical properties are also predicted theoretically.

show abstract

“…Determining or identifying the indices of line and planar features is a classic technique (Hirsch et al, 1965) that remains widely used (Du et al, 2017;Liu et al, 2018;Caillard et al, 2018;Joseph et al, 2018;Du et al, 2018). In most cases, such as determining slip traces or variants, the family of the indices is known, but the specific [uvw] or (hkl) need to be confirmed.…”

Section: Introductionmentioning

confidence: 99%

τompas: a free and integrated tool for online crystallographic analysis in transmission electron microscopy

Xie

Zhang

2020

J Appl Crystallogr

Self Cite

View full text Add to dashboard Cite

τompas (TEM online multi‐purpose analyzing system) is a free and integrated software tool designed to perform online crystallographic analysis in transmission electron microscopy (TEM) experiments. By using sample holder tilt angles as input, τompas can simultaneously simulate pole figures, Kikuchi patterns and feature projections, providing graphical views of the sample crystallography. These simulations are further employed to navigate sample tilting and to quickly interpret experimental Kikuchi patterns and images by image matching, giving self‐consistent indices of features and crystal orientations. These functions are integrated with mouse operations to improve work efficiency. τompas is distributed as a small cross‐platform program that can be installed on a microscope computer to cooperate with other tools.

show abstract

A TEM study of the crystallography of lath-shaped austenite precipitates in a duplex stainless steel

Cited by 13 publications

References 34 publications

Reproducible Orientation Relationships Developed from Phase Transformations—Role of Interfaces

Reproducible Orientation Relationships Developed from Phase Transformations—Role of Interfaces

On Shapes and Orientations of Precipitation Strengthening Phases in an Aged Mg–La Alloy

τompas: a free and integrated tool for online crystallographic analysis in transmission electron microscopy

Contact Info

Product

Resources

About