English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Magnesium alloy AZ31 prepared by hot extrusion and 4 passes of equal-channel angular pressing (EX-ECAP) has ultrane grained microstructure with an average grain size of 900 nm. Grain growth is analysed using a general equation for the grain growth and an Arrhenius equation. The calculated value of the activation energy for grain growth di ers with the annealing temperature. The tted value of activation energy for grain growth in the intermediate temperature range (210 400 ◦C) is in accordance with the results of other authors, but it is shown in this study that such value is abnormally low and physically meaningless. More real values of apparent activation energy in this temperature range were calculated from the model assuming a linear increase of activation energy with increasing annealing temperature. Result of this linear model of evolution of activation energy in the temperature range between 210 400 ◦C is expressed by the interval estimation of apparent activation energy values. It is concluded that the evolution of apparent activation energy can be explained by a change in the mechanism underlying the grain boundary migration. In the low temperature range, the grain boundary di usion is dominant since the material is ultrane grained, whereas at higher temperatures, the lattice self-di usion is more important.

acta physica polonica. a

Activation Energy for Grain Growth of the Isochronally Annealed Ultrafine Grained Magnesium Alloy after Hot Extrusion and Equal-Channel Angular Pressing (EX-ECAP)