Journal ArticleDOI
A general mechanism of martensitic nucleation: Part I. General concepts and the FCC → HCP transformation
Gregory B. Olson,Morris Cohen +1 more
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In this paper, the stacking fault energy is shown to consist of both volume energy and surface energy contributions, and when the volume energy contribution is negative, the fault energy decreases with increasing fault thickness such that fault energy associated with the simultaneous dissociation of an appropriate group of dislocations can be zero or negative.Abstract:
Consideration of the martensitic nucleation process as a sequence of steps which take the particle from maximum to minimum coherency leads to the hypothesis that the first step in martensitic nucleation is faulting on planes of closest packing. It is further postulated that the faulting displacements are derived from an existing defect, while matrix constraints cause all subsequent processes to occur in such a way as to leave the fault plane unrotated, thus accounting for the observed general orientation relations. Using basic concepts of classical nucleation theory, the stacking fault energy is shown to consist of both volume energy and surface energy contributions. When the volume energy contribution is negative, the fault energy decreases with increasing fault thickness such that the fault energy associated with the simultaneous dissociation of an appropriate group of dislocations (e.g. a finite tilt boundary segment) can be zero or negative. This condition leads to the spontaneous formation of a martensitic embryo. For the specific case of the fcc → hcp martensitic transformation in Fe-Cr-Ni alloys, the defect necessary to account for spontaneous embryo formation at the observedM
s temperatures may consist of four or five properly spaced lattice dislocations. Such defects are considered to be consistent with the known sparseness of initial martensitic nucleation sites.read more
Citations
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Mechanical Properties, Microstructure and Phase Composition of Thin Magnetron Sputtered TWIP Steel Foils
TL;DR: In this paper, physical vapor deposition (PVD) by DC magnetron sputtering was used as an alternative way to produce thin metal foils with thicknesses from 20 μm to 50 μm.
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The Effect of Rapid Solidification on Microstructure and Corrosion of Advanced Biomaterial Co-Cr-Mo-C Alloy
TL;DR: In this article, the microstructure and corrosion properties of rapidly solidified Co-Cr-Mo-C alloy were studied using OM, SEM, EDS, XRD, and dynamic potentiostate.
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Investigation of microstructure evolution and martensite transformation developed in austenitic stainless steel subjected to a plastic strain gradient: A combination study of Mirco-XRD, EBSD, and ECCI techniques.
TL;DR: In this article, the evolution of the microstructure and deformation mechanism at different levels of plastic strain are investigated for 304 L austenitic steel with a combination of micro X-ray diffraction, electron backscattered diffraction (EBSD) and electron channeling contrast imaging (ECCI).
Thermal Cooling Effects in the Microstructure and Properties of Cast Cobalt-Base Biomedical Alloys
TL;DR: In this paper, the authors propose a method to solve the problem of the problem: this paper... ]..,.. )].. [1].
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The Effects of Micro-Segregation on Isothermal Transformed Nano Bainitic Microstructure and Mechanical Properties in Laser Cladded Coatings.
TL;DR: The stability of the blocky retained austenite distributed at the interdendritic area was lower than that of film and island-like morphology, which contributed to the ductile and tough nano bainitic coatings with tunable mechanical properties.
References
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The Determination of the Elastic Field of an Ellipsoidal Inclusion, and Related Problems
TL;DR: In this paper, it is shown that to answer several questions of physical or engineering interest, it is necessary to know only the relatively simple elastic field inside the ellipsoid.
Book
Theory of Dislocations
John Price Hirth,Jens Lothe +1 more
TL;DR: Dislocations in Isotropic Continua: Effects of Crystal Structure on Dislocations and Dislocation-Point-Defect Interactions at Finite temperatures.
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The scientific papers
TL;DR: Physical and psychosocial factors associated with psychostimulant use in a nationally representative sample of French adolescents: Specificities of cocaine, amphetamine, and ecstasy use are studied.
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The crystallography of martensite transformations II
J.S Bowles,J.K Mackenzie +1 more
TL;DR: In this paper, the total strain in a martensite transformation was derived from the orientation relationship and the component strains, together with the correspondence, and the dimensions of the initial and final structures.
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