Study of the texture and deformation mechanisms of MA2-1pch magnesium alloy upon rotary swaging

The use of quantitative X-ray texture analysis (QXRTA) (construction of the orientation distribution function (ODF) proceeding from the measurement of direct pole figures) and simulation of the texture formation in the framework of thermoactivation model (TA) are considered to study the features of texture formation in MA2-1pch magnesium alloy subjected to rotary swaging (RS) at 400 – 350°C. A diffuse texture consisting of basic and inclined to the pressing direction basic poles is formed in the alloy when temperature decreases and the total true deformations increase up to ε = 2.77. Model textures match experimental textures rather well when RS is provided by the action of basic ({0001} á1120), prismatic ({1010} á1120ñ) slip and twinning by the systems {1012} á1011ñ, {1011} á1012ñ, {1121} á1126ñ. Mathematical modeling of the textures also shows that the activity of the twinning systems under consideration increases in the sequence {1012} á1011ñ, {1011} á1012ñ, {1121} á1126ñ as the total deformations grow and RS temperature decreases. Those results are consistent with the previously obtained microstructural data. However, the differences in the orientation factors calculated for the initial state of the alloy and state after RS indicated to the activation of the basal slip and twinning systems under consideration, as well as to the difficulty of prismatic sliding. The obtained data are also consistent with the results of mathematical modeling of textures. At a temperature of 350°C at a total true deformation of 2.77 the basic deformation mechanisms (the basic slip and twinning by the systems {1012} á1011ñ, {1011} á1012ñ, {1121} á1126ñ) which ensure texture changes upon RS stimulate an enhance in the mechanical properties of magnesium alloy MA2-1pch bars.

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