Journal ArticleDOI
Morphology of y’ and y” precipitates and thermal stability of inconel 718 type alloys
R. Cozar,André Pineau +1 more
- Vol. 4, Iss: 1, pp 47-59
Reads0
Chats0
TLDR
In this article, the precipitation microstructure varies rapidly with aging temperature and composition, and the influence of composition and aging temperature on the conditions that bring about this compact morphology has been investigated.Abstract:
The precipitation of the γ’ (Ll2) and γ" (DO22) phases has been studied in four alloys Fe-Ni-Cr-Ti-Al-Nb containing a higher Ti + Al/Nb ratio than that of the INCONEL 718 alloy. For these alloys, the precipitation microstructure varies rapidly with aging temperature and composition. Bct γ"particles have always been found to precipitate on γ’ phase. Moreover, by aging three alloys above a critical temperature, a “compact ntorphology” has been observed: cube-shaped γ’ particles coated on their six faces with a shell of γ" precipitate. This microstructure has proved to be very stable on prolonged aging. A thermal stability better than that encountered in nominal INCONEL 718 alloy can thus be achieved. The influence of composition and aging temperature on the conditions that bring about this “compact morphology” has been investigated. A minimal Ti + Al/Nb ratio between 0.9 and 1 has been determined, allowing the “compact morphology” to be obtained.read more
Citations
More filters
Patent
Method for heat treating iron-nickel-chromium alloy
TL;DR: A method for heat treating an age-hardenable iron-nickel-chromium alloy to obtain a morphology of the gamma double prime phase enveloping the gamma-prime phase, the alloy consisting essentially of about 40 to 50% nickel, 7.5 to 14% chromium, 1.75% silicon, 1 to 3% titanium, 0.1 to 0.5% aluminum and 0.02 to 1% carbon as mentioned in this paper.
Journal ArticleDOI
Cutting Apart of γ″ Precipitates by Dislocations Emitted from Nanoscale Surface Notches in Ni-Base Alloy 725
TL;DR: In this article, a high-resolution transmission electron microscopy study is presented that gives evidence for cutting apart of DO22 Ni3Nb γ precipitates by dislocations emitted from nanoscale notches on free surfac...
Journal ArticleDOI
Using Variant Selection to Facilitate Accurate Fitting of γ ″ Peaks in Neutron Diffraction
Ruiyao Zhang,H. L. Qin,Z. N. Bi,Jun Li,Shiladitya Paul,T. L. Lee,Bogdan Nenchev,J. Zhang,Saurabh Kabra,Joe Kelleher,Hongbiao Dong +10 more
TL;DR: In this article, a variant selection method was proposed to increase the intensity of γ″ peaks and to facilitate accurate fitting, which resulted in greater peak intensities in neutron diffraction patterns, allowing both the Pawley refinement and single peak fitting to be performed.
Journal ArticleDOI
An investigation of the plastic work to heat conversion of wrought and laser powder bed fusion manufactured Inconel 718
John Varga,Owen T. Kingstedt +1 more
TL;DR: In this paper, the Taylor-Quinney coefficient (β) of Inconel 718 (IN718) was investigated for three material conditions, namely wrought IN718, laser powder bed fusion (LPBF), and one that has been recrystallized through a solutionizing heat treatment.
Proceedings ArticleDOI
Analysis of microstructural properties of IN 718 after high speed forging
TL;DR: In this paper, a modified TTT-diagram is suggested for IN 718 exposed to high strain rates, where the precipitates develop much earlier than predicted, which is not applicable to the material exposed to a high strain rate.
References
More filters
Journal ArticleDOI
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.
Journal ArticleDOI
Déformations de cohérence d'un précipité quadratique
TL;DR: In this paper, exact expressions for the elastic field due to a perfectly coherent precipitate having the form of a rectangular parallelepiped, the material being supposed elastically homogeneous and isotropic.
Journal ArticleDOI
The microstructure of 706, a new Fe−Ni-base superalloy
TL;DR: In this article, the phase relationships of Alloy 706 alloy were investigated and it was shown that on the basis of chemistry and micro-structural response, Alloy 606 alloy can be considered to be intermediate to the well-known alloys, 718 and 901.
Journal ArticleDOI
Heterogeneous precipitation of metastable γ′-ni3ti in a nickelbase alloy
TL;DR: In this article, the effect of prior deformation on the precipitation of L12 γ′-Ni3Ti in nickel-base Alloy 901 was investigated by thin foil microscopy.
Journal ArticleDOI
Fine Faults and Crystal Structures of Precipitates in Fe-Mo and Fe-W Alloys
Kōhei Yagisawa,Hiroshi Fujita +1 more
TL;DR: In this paper, the crystal structure and two-dimensional faults of the precipitates in Fe-Mo alloys were investigated using electron microscopic method, and the faults were found on {00.1}hex, {10.0}hex and {100}hex planes.