Investigation of the reaction of discontinuous phase precipitation in Ni-Cr-Al alloy

Петров, В. А.; Sukhovarov, V. F.; Strokatov, R. D.

doi:10.1007/bf00901862

Cited by 2 publications

(4 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As the supersaturation of Cr in the g matrix increases, G E may increase, and thus s will decrease through Eq. (8). As can be seen in Fig.…”

Section: Kinetic Analysismentioning

confidence: 65%

“…The formation of the multiphase microstructure has been experimentally examined by various investigators. [7][8][9] For instance, Komatsu et al 7) observed the crystallographic orientation relationship between the a and g lamellae by transmission electron microscopy (TEM). In their experiment, a polycrystalline Ni-38Cr-3.8Al alloy was homogenized at 1 473 K for 2 h and then isothermally annealed at temperatures of 773-1 173 K for various times up to 5 h.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of Al on Kinetics of Discontinuous Precipitation in Ni–38Cr Alloy

Ueta

Kajihara

2010

ISIJ Int.

View full text Add to dashboard Cite

The influence of Al on the kinetics of discontinuous precipitation in the Ni-Cr system was experimentally examined using ternary Ni-38Cr-Al alloys with Al concentrations of 3.8 mass% and 4.2 mass%. The ternary alloys were homogenized at 1 473 K for 16 h, solution treated at 1 473-1 493 K for 30 min, and then isothermally annealed in the temperature range of 773-1 073 K for various times up to 50 h. Due to the solution heat treatment, both ternary alloys show the polycrystalline single-phase microstructure of the Ni-rich solidsolution (g) phase with the face-centered cubic structure. In the early stages of isothermal annealing, however, fine particles of the Ni 3 Al (gЈ) phase with the L1 2 structure are formed in the g matrix by continuous precipitation. On the other hand, the cell of the lamellar microstructure consisting of the g phase and the Cr-rich solid-solution (a) phase with the body-centered cubic structure is formed along the grain boundary of the g matrix and then grows into the g matrix. The fine particles of the gЈ phase are dispersed also in the g phase of the cell. The migration distance of the moving cell boundary is proportional to the annealing time. Thus, the growth rate of the cell is constant independent of the annealing time. The growth rate and the interlamellar spacing of the cell monotonically increase with increasing annealing temperature. A kinetic model was used to analyze quantitatively the relationship between the growth rate and the interlamellar spacing. Although the discontinuous precipitation in the ternary Ni-38Cr-Al alloys occurs in a complicated manner, the analysis indicates that the growth of the lamellar cell is controlled by the boundary diffusion of Cr along the moving cell boundary.

show abstract

“…As the supersaturation of Cr in the g matrix increases, G E may increase, and thus s will decrease through Eq. (8). As can be seen in Fig.…”

Section: Kinetic Analysismentioning

confidence: 65%

Section: Introductionmentioning

confidence: 99%

Influence of Al on Kinetics of Discontinuous Precipitation in Ni–38Cr Alloy

Ueta

Kajihara

2010

ISIJ Int.

View full text Add to dashboard Cite

show abstract

“…Using the relationships xm = , xp = and x0 = for and those xm = , xp = and x0 = for , r was calculated from Eq. (8). The result is listed at the last column in Table 3.…”

Section: )mentioning

confidence: 82%

“…The formation of the multiphase microstructure has been experimentally studied by various investigators. [7][8][9] For example, Kawase et al. 9) examined the crystallographic orientation relationships among the α, γ and γ ' phases in a Ni-39Cr-3.8Al alloy by transmission electron microscopy (TEM).…”

Section: Introductionmentioning

confidence: 99%

Influences of Co, Cu and V on Kinetics of Discontinuous Precipitation in the Ni^|^ndash;Cr System

2013

View full text Add to dashboard Cite

The effects of Co, Cu and V on the kinetics of discontinuous precipitation in the Ni-Cr system were experimentally examined using ternary Ni-39Cr-1.0Co, Ni-39Cr-1.2Cu and Ni-39Cr-0.89V alloys. The alloys were homogenized at 1 423 K for 3 h, solution treated at 1 423 K for 1 h, and then isothermally annealed in the temperature range of 873-1 023 K for various times up to 2 300 h. Due to the solution heat treatment, all the alloys show the polycrystalline single-phase microstructure of the Ni-rich solid-solution (γ ) phase with the face-centered cubic structure. During isothermal annealing, however, the cell of the lamellar microstructure composed of the γ phase and the Cr-rich solid-solution (α) phase with the bodycentered cubic structure is produced along the grain boundary of the γ matrix and then grows into the γ matrix. At each annealing temperature, the migration distance of the moving cell boundary increases in proportion to the annealing time. Thus, the growth rate of the cell is constant independent of the annealing time. The growth rate and the interlamellar spacing of the cell almost monotonically increase with increasing annealing temperature at 873-1 023 K. The cell growth is slightly accelerated by Cu but not by Co and V. However, the acceleration is less remarkable at 1 023 K. A kinetic model for the binary discontinuous precipitation controlled by boundary diffusion was used to analyze quantitatively the experimental result. In the moving cell boundary, the thermodynamic interaction is attractive between Cr and V but repulsive between Cr and Cu. Therefore, it is anticipated that the boundary diffusion of Cr along the moving cell boundary may be expedited by V but retarded by Cu. According to the analysis, however, the Cr boundary diffusion is hardly affected by Cu and V as well as Co. On the other hand, the boundary diffusion is lightly faster for Cu than for Co but slower for V than for Co. Consequently, for Cu and V, the thermodynamic and diffusional contributions to the Cr boundary diffusion are compensated each other.

show abstract

Investigation of the reaction of discontinuous phase precipitation in Ni-Cr-Al alloy

Cited by 2 publications

References 3 publications

Influence of Al on Kinetics of Discontinuous Precipitation in Ni–38Cr Alloy

Influence of Al on Kinetics of Discontinuous Precipitation in Ni–38Cr Alloy

Influences of Co, Cu and V on Kinetics of Discontinuous Precipitation in the Ni^|^ndash;Cr System

Contact Info

Product

Resources

About