Dynamic strain aging in Czochralski-grown silicon single crystals

The effects of aging on the upper yield stress τup and serrated flow have been studied in MnO single crystals at 900 °C for oxygen partial pressures ρO2 of 10−11 and 10−7 Pa. Aging initially increases τup as a consequence of segregation of aliovalent impurities to dislocations for both ρO2 values. For long aging times and ρO2 = 10-11 Pa, serrated flow accompanied by solute softening is observed. The data fit predictions of a Portevin-Le Chatelier model for serrations, but with impurity atmospheres causing softening instead of hardening. This is believed to result from changes in local defect equilibria caused by segregation of impurities with valences greater than two to dislocations.

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The plastic deformation of 18R long range ordered Cu-Zn-Al single crystals the temperature and strain rate dependence of the critical stress and the influence of dynamic strain aging

Materials Science and Engineering A ◽

10.1016/s0921-5093(97)00378-x ◽

1997 ◽

Vol 234-236 ◽

pp. 893-895 ◽

Cited By ~ 5

Author(s):

A. Cuniberti ◽

M. Ahlers ◽

R. Romero

Keyword(s):

Plastic Deformation ◽

Strain Rate ◽

Single Crystals ◽

Long Range ◽

Dynamic Strain Aging ◽

Critical Stress ◽

Strain Aging ◽

Rate Dependence ◽

Strain Rate Dependence ◽

Dynamic Strain

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Strain Aging behavior In NiAI Microalloyed with Interstitial and Substitutional Solutes

MRS Proceedings ◽

10.1557/proc-460-499 ◽

1996 ◽

Vol 460 ◽

Author(s):

M. L. Weaver ◽

R. D. Noebe ◽

M. J. Kaufman

Keyword(s):

Single Crystals ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Dynamic Strain ◽

Aging Behavior ◽

Co Doping ◽

Polycrystalline Alloys ◽

Substitutional Impurities

ABSTRACTDynamic strain aging has been investigated in polycrystalline NiAl alloys containing combined additions of interstitial and substitutional impurities. The results indicate that strain aging can be enhanced in polycrystalline alloys containing concentrations of silicon or iron in excess of 0.15 at.% in addition to conventional levels of carbon. This co-doping leads to very dramatic strain aging events, comparable to those typically observed in single crystals. This effect will be discussed with respect to conventional theories of strain aging.

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Dynamic strain aging in magnesium oxide single crystals

Materials Science and Engineering ◽

10.1016/0025-5416(73)90131-6 ◽

1973 ◽

Vol 12 (2) ◽

pp. 87-93 ◽

Cited By ~ 10

Author(s):

M. Srinivasan ◽

T.G. Stoebe

Keyword(s):

Single Crystals ◽

Magnesium Oxide ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Dynamic Strain

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Serrated Yield Behavior in Nial Single Crystal

MRS Proceedings ◽

10.1557/proc-364-419 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 1

Author(s):

J. M. Brzeski ◽

J.E. Hack ◽

R. Darolia

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Single Crystal ◽

Single Crystals ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Fracture Behavior ◽

Recent Model ◽

Dynamic Strain ◽

Yield Behavior

AbstractDynamic strain aging has been characterized in standard purity NiAl single crystals during compression testing. The activation energy for the process suggests carbon and oxygen as the most likely agents. Experimental data is compared with a recent model and implications for the fracture behavior of NiAl are considered.

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