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In situ Transmission Electron Microscopy Tensile Tests of a Peak- to Overaged γ′-strengthened Nickel Base Alloy

Published online by Cambridge University Press:  01 July 2005

Dietmar Baither ,
Volker Mohles  and
Eckhard Nembach
Dietmar Baither*
Affiliation:
Institut für Materialphysik, Universität Münster, D-48149 Münster, Germany
Volker Mohles
Affiliation:
Institut für Metallkunde und Metallphysik, Rheinisch-Westfälische Technische Hochschule, D-52056 Aachen, Germany
Eckhard Nembach
Affiliation:
Institut für Materialphysik, Universität Münster, D-48149 Münster, Germany
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

The commercial nickel base alloy NIMONIC PE16 is strengthened by nano-scale spherical coherent precipitates of the intermetallic γ′-phase Ni3(Al,Ti). A bulk polycrystalline specimen of NIMONIC PE16 was aged such that it was in the transition range from the peak- to the overaged state. This transition limits the duration of technically useful aging treatments of structural particle strengthened materials. Thin foils prepared from this specimen were stretched inside a transmission electron microscope, and the dislocation processes were observed under full load. Two dislocations with identical Burgers vectors of the type 1/2〈110〉 form a pair and glide together. The leading 1/2〈110〉 dislocation bypasses the γ′-precipitates and the trailing one shears them. These dislocation processes are also discussed with reference to the results of computer simulations.

Keywords

Computer simulationMechanical propertiesTransmission electron microscopy (TEM)
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 7 , July 2005 , pp. 1722 - 1727
Copyright
Copyright © Materials Research Society 2005

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References

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