Influence of Joule Effect Heating on Recrystallization Phenomena in Inconel 718

An apparatus for the measurement of the total hemispherical emittance and specific heat of metals has been developed. The measurement principle is based on the calorimetric technique: the sample, heated by Joule effect and placed in a vacuum chamber, exchanges radiative heat transfer with the walls of the container, kept at a relatively low temperature. Emittance is deduced from the radiative heat transfer laws at the steady state. When the heating power is switched off, the specific heat of the sample can be recovered from the time history of the sample temperature during the cooling transient. Measurements have been performed on samples of aluminum Anticorodal alloy and Inconel 718 alloy under different surface conditions in the 350-635K range.

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The Nature of Delta Phase Precipitation in Inconel 718

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055916 ◽

1982 ◽

Vol 40 ◽

pp. 724-725

Author(s):

L. S. Lin ◽

C. C. Law

Keyword(s):

Inconel 718 ◽

Base Alloy ◽

High Strength ◽

Physical Metallurgy ◽

Nickel Base Alloy ◽

Phase Precipitation ◽

Weight Percentage ◽

Delta Phase ◽

The Subject ◽

Nickel Base

Inconel 718, a precipitation hardenable nickel-base alloy, is a versatile high strength, weldable wrought alloy that is used in the gas turbine industry for components operated at temperatures up to about 1300°F. The nominal chemical composition is 0.6A1-0.9Ti-19.OCr-18.0Fe-3Mo-5.2(Cb + Ta)- 0.1C with the balance Ni (in weight percentage). The physical metallurgy of IN 718 has been the subject of a number of investigations and it is now established that hardening is due, primarily, to the formation of metastable, disc-shaped γ" an ordered body-centered tetragonal structure (DO2 2 type superlattice).

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A Note on the Volume Change of Tires During Warm-Up

Tire Science and Technology ◽

10.2346/1.2167226 ◽

1976 ◽

Vol 4 (4) ◽

pp. 252-255

Author(s):

D. J. Schuring

Keyword(s):

Thermal Expansion ◽

Volume Change ◽

Joule Effect ◽

Warm Up ◽

Initial Decrease

Abstract Increasing the temperature produces a decrease in tire volume. After longer times the volume tends to increase again. The initial decrease is attributed to the predominance of the Gough-Joule effect over thermal expansion and the delayed increase, to creep.

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