| Autor: |
Jean-Luc Martin, B. Lo Piccolo, Joël Bonneville |
| Rok vydání: |
2000 |
| Předmět: |
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| Zdroj: |
Intermetallics. 8:1013-1018 |
| ISSN: |
0966-9795 |
| DOI: |
10.1016/s0966-9795(00)00047-9 |
| Popis: |
Using two transient mechanical tests which are described (repeated load relaxations and repeated creep tests) some microscopic parameters of the deformation processes in Ni 3 Al compounds such as the activation volume V of the dislocation velocity and the exhaustion rate of mobile dislocations are determined. V values in the range of 80 to 350 b 3 (Ni 75 Al 25 polycrystal at 300 K) that dislocation mobility is thermally activated, while large values of the exhaustion parameter correlate well with the work-hardening coefficient. This new information about quantitative aspects of dislocation exhaustion are supported by the observation of a yield point at reloading subsequent to the relaxation transient. The variation of the amplitude of this yield point as a function of temperature is similar to the variation of the exhaustion parameter. Both curves peak at 500 K which is also the peak temperature of the work-hardening coefficient. The variation with temperature of this latter parameter is discussed in the light of the present results. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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