Abstract
The article presents the results of the experimental test on the creep process of AlMgSi alloy wires (series 6xxx) under the conditions of variable stress. A theoretical analysis of equivalency rheological results of stress and temperature changes by means of Bayley-Norton function, which describes well the low-temperature aluminum alloys creep, was carried out. Therefore, the described issue became one-dimensional. On the basis of experimental tests, it has been proved that negative gradients of stress and temperature may generate three types of rheological behaviour, such as: Temporary decrease of creep speed (type 1), Temporary stop of creep deformation (‘dead’ time)—type 2 and reverse after creep (type 3).
The applicable nature of tests is placed in overhead power lines, which undergo cyclical stress- and time-dependent operation. Such a nature of conductor operation creates favourable conditions to decrease creep intensity, whereas its history and value and speed of stress and temperature lowering decide whether conductor rheological activity loss will take place. The actual material parameter controlling the conductor rheological behaviour is stress and temperature rheological equivalent. The article contains exemplary results of current-carrying capacity changes of AlMgSi alloy conductor on a given temperature range, and the calculations include actual creep characteristic and cumulated rheological inactivity caused by negative gradients of stress and temperature.
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Open Access This is an open access article distributed under the terms of the Creative Commons Attribution Noncommercial License (https://creativecommons.org/licenses/by-nc/2.0), which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
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Knych, T., Mamala, A. & Smyrak, B. Phenomenology of the creep process of a precipitation-hardenable AlMgSi alloy wires for overhead power lines. Experimental tests. Simulation. Mech Time-Depend Mater 13, 163–181 (2009). https://doi.org/10.1007/s11043-009-9079-8
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DOI: https://doi.org/10.1007/s11043-009-9079-8
Keywords
- Creep
- Rheology
- Dead time
- Rheological equivalent
- Rheological inactivity
- Rheological behavior
- Low temperature creep
- Creep in trend of leap stress decrease
- AlMgSi
- Alloy wires
- Aluminium alloys
- AlMgSi, overhead lines
- Power lines, aluminium conductor
- Heat treatability alloys
- ACSR
- AAAC
- Secondary creep
- Primary creep
- Regress state
- Alloys 6xxx
- Wire
- Aluminium wires
- Heat capacity
- New conductors
- Stress change
- Temperature change