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interdiffusion

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Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003741
EISBN: 978-1-62708-177-1
... Abstract Interdiffusion microstructures appear as a region on either side of the original interface of contact between two materials. This article outlines the principles used in analyzing various interdiffusion microstructures: binary systems, copper-base systems, nickel-base systems...
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Published: 01 January 1986
Fig. 88 Experimental results for the binary γ interdiffusion coefficient, D ˜ γ , as a function of temperature. The error bar on D ˜ γ at 610 °C (1130 °F) indicates the possible range of D ˜ γ values at that temperature. Source: Ref 72 More
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Published: 01 December 2004
Fig. 1 An interdiffusion microstructure in a Ni-Cr-Al diffusion couple made by bonding a γ + β alloy (left) to a γ + γ′ alloy (right) ( Ref 2 ). The microstructure can be expressed in shorthand as γ + β | γ + β > γ + γ′. More
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Published: 01 December 2004
Fig. 2 Example of an interdiffusion microstructure map prepared for Ni-Cr-Al, gamma-plus-beta coatings on a superalloy annealed at 1200 °C (2190 °F). The initial γ + γ′ composition is noted by a star. Source: Ref 6 More
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Published: 01 December 2004
Fig. 4 A secondary-electron image of the interdiffusion zone in a Mo/MoSi 2 diffusion couple annealed at 1500 °C (2730 °F) for 6 h ( Ref 8 ). Here multiphase layers can be seen, which are unexpected for binary systems. More
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Published: 01 December 2009
Fig. 15 Illustration of the amount of interdiffusion as defined by the solute, S, that has entered the right side of the couple from the left side. In both cases shown in the figure, the value of S is negative because solute has left the right side. Source: Adapted from Ref 5 More
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Published: 01 December 2009
Fig. 4 Example of Boltzmann-Matano calculation for a single-phase interdiffusion t with end-member composition of c i − and c i + . The Matano plane is located at z 0 and is chosen such that the two shaded areas, E and F, are equal. The diffusion coefficient More
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Published: 01 December 2009
Fig. 5 Example of the Sauer-Freise method to calculate the interdiffusion coefficient for face-centered cubic cobalt-nickel at 1150 °C. (a) Measured composition profile after 1000 h at 1150 °C. (b) Calculated interdiffusion coefficient at 1150 °C. Source: Ref 10 More
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Published: 01 December 2009
Fig. 7 Example of the calculation of the intrinsic diffusion and interdiffusion coefficients for the iron-nickel system at 1200 °C. Thermodynamic factors (a) and mobilities (b) for iron and nickel as functions of composition are multiplied to calculate the intrinsic diffusion coefficients More
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Published: 01 December 2009
Fig. 10 Comparison of calculated and measured interdiffusion coefficients for the nickel-tungsten system as a function of composition for temperatures ranging from 900 to 1300 °C. (a) Calculated diffusivities before optimization; observed composition dependence is entirely from the composition More
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Published: 01 January 2006
Fig. 11 Duplex coating consisting of an overlay coating (O) with an aluminide layer (A) on top. The interdiffusion zone with the base metal (B) is indicated by the letter I. There is another interdiffusion zone between A and O. Lactic acid etch More
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Published: 01 January 2006
Fig. 29 Duplex coating consisting of an overlay coating (O) with an aluminide layer (A) on top. There is an interdiffusion zone with the base metal (B) and another interdiffusion zone between A and O. Lactic acid etch. See the article “Corrosion of Industrial Gas Turbines” in this Volume. More
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006787
EISBN: 978-1-62708-295-2
... failures, molten salts for energy storage, and degradation and failures in gas turbines. The article describes the effects of environment on aero gas turbine engines and provides an overview of aging, diffusion, and interdiffusion phenomena. It also discusses the processes involved in high-temperature...
Series: ASM Handbook
Volume: 22A
Publisher: ASM International
Published: 01 December 2009
DOI: 10.31399/asm.hb.v22a.a0005430
EISBN: 978-1-62708-196-2
... k j = diffusion coefficient for the diffusing component, j , with respect to the composition gradient of component k , in the volume-fixed frame of reference (m 2 /s) D ~ k j n = interdiffusion coefficient, where n is the dependent component (m 2 /s) f...
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Published: 15 December 2019
including interdiffusion; RZ, reaction zone where compound formation was observed. Source: Ref 59 More
Series: ASM Handbook
Volume: 22A
Publisher: ASM International
Published: 01 December 2009
DOI: 10.31399/asm.hb.v22a.a0005439
EISBN: 978-1-62708-196-2
.... For example, high-temperature coatings interdiffuse with parts they are meant to protect. By this process, critical elements in the coating diffuse into the underlying part, thereby reducing their oxidation resistance and often reducing their mechanical properties. Also, oxidation of high-temperature...
Series: ASM Handbook
Volume: 22B
Publisher: ASM International
Published: 01 November 2010
DOI: 10.31399/asm.hb.v22b.a0005536
EISBN: 978-1-62708-197-9
... variable, z is distance, and [ D ] is a matrix that contains the interdiffusion coefficients. Assuming that [ D ] is concentration dependent gives a system of coupled parabolic partial differential equations, and these equations must be solved numerically so that the evolution of the concentration...
Series: ASM Handbook
Volume: 13A
Publisher: ASM International
Published: 01 January 2003
DOI: 10.31399/asm.hb.v13a.a0003590
EISBN: 978-1-62708-182-5
... result in tensile stress; wustite is an important example, varying from Fe 0.95 O in equilibrium with the metal to as little as Fe 0.84 O in equilibrium with Fe 3 O 4 at 1370 °C (2500 °F). Interdiffusion in a reacting alloy can generate stresses (i.e., Kirkendall effect) when alloy components have...
Series: ASM Handbook
Volume: 4A
Publisher: ASM International
Published: 01 August 2013
DOI: 10.31399/asm.hb.v04a.a0005775
EISBN: 978-1-62708-165-8
... at temperatures in excess of 1000 °C (1830 °F), interdiffusion of the coating will cause further degradation, and therefore, practical coating life is limited to operating temperatures of 870 to 980 °C (1600 to 1800 °F). Pack compositions, process temperatures, and process times depend on the type of base...
Series: ASM Handbook
Volume: 13C
Publisher: ASM International
Published: 01 January 2006
DOI: 10.31399/asm.hb.v13c.a0004158
EISBN: 978-1-62708-184-9
... portion and an interdiffusion zone. The interdiffusion zone contains various intermetallic compounds, including sigma phase, due to the loss of elements from the base metal to form the coating. (This sigma phase is not detrimental.) Fig. 10 Micrograph of a nickel-aluminide coating. As-polished...