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Highlights: [•] Samples perpendicular to ED exhibit lower yield stress than these parallel to ED. [•] Yield stress of sample perpendicular to ED increases if pre-compressed along ED. [•] The change of orientation leads to a different twin characteristic. [ABSTRACT FROM AUTHOR]

In the present investigation, microstructure, texture and mechanical properties of Mg-3Mn alloys fabricated by hot extrusion process with the extrusion temperatures of 250 °C and 300 °C were investigated. The results revealed that the samples exhibited the refined microstructure and weakened basal texture. Refined microstructure of the samples was attributed to the dynamic precipitates suppressing the recrystallization grain growth during extrusion process. Weakened basal texture of the samples was explained as a result of particle stimulated nucleation (PSN) promoted by coarsened Mn precipitates altering the texture of extruded profiles during recrystallization by orienting the c-axis of grains at an angle that favors basal slip activity. As a result, the samples exhibited the high tensile elongation and good yield strength at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: The current paper investigates the effect of extension twins identified by using electron backscattered diffraction on the interrupted properties of an extruded Mg–3Al–1Zn (AZ31) alloy. Compressive and recompressive tests are conducted along extrusion direction (ED). It is discovered that the yield strength of recompression is enhanced due to grain refinement by extension twins. The reinforcement effect of extension twins on the yield stress of recompression is mainly reflected at the stage of small deformation while the improvement of yield strength is mainly attributed to the pile-up and intersection of dislocations as large deformation occurs. Furthermore, the yield stress of recompression is identical to the interrupted stress of precompression. In situ observation reveals that some twins generated in precompression could also become thicker in the following recompression. [Copyright &y& Elsevier]

Abstract: The crystal structure of the compound Al2ErGe2 has been determined by X-ray powder diffraction technique and refined by using Rietveld method. The compound Al2ErGe2 crystallizes in a hexagonal Al2CaSi2-type structure (space group , a =0.41781(9)nm, c =0.66698(1)nm, z =1). Lattice thermal expansion studies on the compound were carried out in the temperature range from 298 to 913K. The variation of the unit cell parameters shows that the lattice parameters increase with the increase in temperature. The coefficients of average relative thermal expansion of the compound along various axes were presented. [Copyright &y& Elsevier]