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1. Strain partitioning-induced anisotropy in thermomechanically processed magnesium alloys comprised of earth-abundant elements

   https://doi.org/10.1016/j.scriptamat.2025.116659  

   Bhattacharyya, Jishnu J; Faberman, Seth; Sullivan, Aaron; Saha, Mainak; Sasaki, Taisuke; Agnew, Sean R (June 2025, Scripta Materialia)

   Dilute Mg alloys based upon earth-abundant elements, e.g., Al, Ca, and Zn have attractive combinations of strength, ductility, and workability. Even higher strength can be obtained in work-hardened material without the heat treatments required to induce Guinier-Preston zone strengthening of previously studied versions of these alloys. This stems from a slightly stronger crystallographic texture than is present after solutionizing, a high dislocation density, and to a lesser degree, a fine distribution of globular Zn-rich precipitates. The anisotropic plastic response of sheet material is described using an elasto-viscoplastic self-consistent (EVPSC) polycrystal model. Strain partitioning between grains during rolling-induced strain hardening is held responsible for the yield strength, ductility, and especially, strain hardening anisotropy. Texture-induced plastic anisotropy is well- known, but the effect of strong partitioning of strain between variously oriented grains is critical to explain what may be classified as a sort of strain path change (generalized Bauschinger) effect. 

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2. Compressive-tensile yield asymmetry and aging-induced embrittlement in a selective laser melted 17-4 PH stainless steel

   https://doi.org/10.1016/j.msea.2025.149537  

   Wang, William; Farkoosh, Amir R; Raturi, Abheepsit; Eliaz, Noam; Seidman, David N (January 2026, Materials Science and Engineering: A)

   We studied the compressive-tensile yield asymmetry (CTYA) and its sensitivity to standard post-processing treatments for a 17-4 PH stainless steel processed with selective laser melting (SLM). Quasistatic tensile and compression tests at ambient temperatures reveal a consistent CTYA for all tested conditions, with compressive yield strengths exceeding tensile values. In the as-printed state, yield asymmetry (Δσ) is ∼113 MPa. Stress-relieving at 300 °C results in only a marginal decrease in asymmetry (Δσ ∼109 MPa), suggesting that the residual stresses generated during SLM have a negligible effect on the observed CTYA. Our analyses indicate that “dynamic softening” due to a stress-assisted austenite-to-martensite transformation governs the yield behavior similar to that observed in transformation-induced plasticity (TRIP)-assisted steels containing mechanically unstable retained austenite. This interpretation is further supported by the increased asymmetry, Δσ ∼127 MPa, observed in a solution-treated and aged specimen, which has a slightly higher retained austenite volume fraction (24 % vs. 21 %). Direct aging at 482 °C of the as-printed steel with a ferritic microstructure causes severe embrittlement. Brittle fracture occurs under tensile stresses well below the yield strength. This pronounced loss of ductility most likely arises from a strong <001> fiber texture along the build direction developed during SLM, which is known to promote cleavage-type fracture on {001} planes. A solution treatment at 1000 °C for 1 h, austenitizes the microstructure completely, and subsequent quenching produces a predominantly martensitic structure with a much weaker crystallographic texture, which restores a favorable strength-ductility balance after aging. 

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3. Hardness anisotropy in Mg: The influence of extension twining and 〈c + a〉 dislocation activity under nanoindentations

   https://doi.org/10.1016/j.scriptamat.2025.116832  

   Motallebi, Reza; Lai, Yi-Cheng; Walker, Christopher C; Dong, Jiaqi; Pharr, George M; Xie, Kelvin Y (October 2025, Scripta Materialia)

   Nanoindentation was performed on individual grains of a polycrystalline Mg sample with c-axis declination angles ranging from parallel (0°) to perpendicular (90°) to the c-axis. Hardness was highest at ∼0°, decreased up to ∼55°, and then increased at ∼90° to an intermediate level. At ∼0°, high-density 〈c + a〉 dislocations extended deep into the crystal, contributing to high hardness. At ∼55°, 〈c + a〉 dislocations were confined near the indent, and occasional extension twinning reoriented the crystal to ∼45°, promoting 〈a〉 slip in both matrix and twin, leading to low hardness. At ∼90°, extension twinning reoriented the crystal to ∼0°, inducing texture hardening and intermediate hardness. Despite the complex stress state in nanoindentation, which fundamentally differs from the uniaxial stress in bulk tensile and compression tests, the combined contributions of dislocation and twinning still give rise to measurable hardness anisotropy, suggesting nanoindentation as a high-throughput technique for probing orientation-dependent mechanical behavior in Mg. 

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4. Predicting textural variability effects in the anisotropic plasticity and stability of hexagonal metals: Application to magnesium and its alloys

   https://doi.org/10.1016/j.ijplas.2020.102762  

   Indurkar, P.P; Baweja, S; Perez, R; Joshi, S.P. (April 2020, International journal of plasticity)

   This work systematically investigates the texture-property linkages in hexagonal close-packed (hexagonal) materials using a three-dimensional computational crystal plasticity approach. Magnesium and its alloys are considered as a model system. We perform full-field, large-strain, micromechanical simulations using a wide range of surrogate textures that also sample several experimental datasets for a range of Mg alloys. The role of textural variability and the associated sensitivity of deformation mechanisms on the evolution of the macroscopic plastic anisotropy and strength asymmetry is mapped under uniaxial tensile and compressive loading along the material principal and off-axes orientations. To assess the role of crystallographic plastic anisotropy, two distinct material datasets are simulated, which represent pure and alloyed magnesium. The results provide insights into experimental observations reported for magnesium alloys over a range of materials textures. We discuss potential implications on the damage tolerance from the aggregate plastic anisotropy arising from intrinsic crystallographic and textural effects. 

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5. The Effect of Extrusion Temperatures on Microstructure and Mechanical Properties of Mg-1.3Zn-0.5Ca (wt.%) Alloys

   https://doi.org/10.3390/cryst11101228  

   Zhang, Honglin; Xu, Zhigang; Kecskes, Laszlo J.; Yarmolenko, Sergey; Sankar, Jagannathan (October 2021, Crystals)

   The present work mainly investigated the effect of extrusion temperatures on the microstructure and mechanical properties of Mg-1.3Zn-0.5Ca (wt.%) alloys. The alloys were subjected to extrusion at 300 °C, 350 °C, and 400 °C with an extrusion ratio of 9.37. The results demonstrated that both the average size and volume fraction of dynamic recrystallized (DRXed) grains increased with increasing extrusion temperature (DRXed fractions of 0.43, 0.61, and 0.97 for 300 °C, 350 °C, and 400 °C, respectively). Moreover, the as-extruded alloys exhibited a typical basal fiber texture. The alloy extruded at 300 °C had a microstructure composed of fine DRXed grains of ~1.54 µm and strongly textured elongated unDRXed grains. It also had an ultimate tensile strength (UTS) of 355 MPa, tensile yield strength (TYS) of 284 MPa, and an elongation (EL) of 5.7%. In contrast, after extrusion at 400 °C, the microstructure was almost completely DRXed with a greatly weakened texture, resulting in an improved EL of 15.1% and UTS of 274 MPa, TYS of 220 MPa. At the intermediate temperature of 350 °C, the alloy had a UTS of 298 MPa, TYS of 234 MPa, and EL of 12.8%. 

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