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• An automated analysis framework of strain partitioning and both intra- and inter-granular deformation mechanisms is proposed. • HRDIC-EBSD data fusion and computer vision were used to segment strain field into various material-meaning clusters. • The pixel-based slip activity, considering SB morphology, was obtained statistically. • Inter-granular accommodating mechanisms, including GB strain, slip transfer, and GBS, were quantitatively analyzed. • The framework was validated by application to Mg-10Y, which can be applied to other materials. Simultaneously investigating strain partitioning and the underlying deformation mechanisms for both the grain interior and the grain boundary (GB) is essential for understanding the complex plastic deformation of hexagonal close-packed metals. To this end, an automated analysis framework based on high-resolution digital image correlation (HRDIC) and electron backscatter diffraction (EBSD) data fusion and computer vision, integrating nanoscale resolution and a large field of view, is proposed. This framework consists of: (1) HRDIC-EBSD data fusion; (2) Segmenting the strain field into individual grains each with a core and a mantle; (3) Data clustering of the Matrix and slip bands (SBs) for each grain; (4) Full slip system (SS) identification and SS assignment to the SBs. The capabilities of this framework were demonstrated on Mg-10Y during compression. The strain field data, which was segmented into different clusters, including grain mantle, grain core, Matrix, and SBs, was analyzed statistically and quantitatively. The pixel-based slip activity, which considers the SB morphology, was obtained from a statistical perspective. Inter-granular accommodating mechanisms, including GB strain, slip transfer, and GB sliding, were quantitatively analyzed. Overall, this analysis framework, which can be applied to other materials, can automatically and statistically evaluate both nanoscale strain fields and underlying intra- and inter-granular deformation mechanisms grain-by-grain. This work provides valuable experimental insights into plastic deformation and accommodation mechanisms for polycrystals. [Display omitted] [ABSTRACT FROM AUTHOR]

Absorbable metals have the potential to serve as the next generation of temporary medical implant devices by safely dissolving in the human body upon vascular tissue healing and bone regeneration. Their implementation in the market could greatly reduce the need of costly and risky additional surgeries for either implant replacement or removal, often required in current permanent implants. Despite the extensive research done over the last two decades on magnesium (Mg) and iron (Fe) based alloys, they have not generally shown a satisfactory combination of mechanical properties, biocompatibility and controlled degradation rate in the physiological environment. Consequently, zinc (Zn) based alloys were introduced in the last few years as alternative materials to overcome the limitations of Fe and Mg-based alloys. The blend of different alloying elements and processing conditions have led to a wide variety of Zn-based alloys having tunable mechanical properties and corrosion rates. This review provides the most recent progress in the development of absorbable Zn-based alloys for biomedical implant applications, primarily for cardiovascular and orthopedic devices. Their biocompatibility, processability and metallurgical aspects, as well as their mechanical behavior and corrosion properties are presented and discussed, including their opportunities, limitations and future research directions. Temporary orthopedic bioimplants have become increasingly popular as they offer an alternative to prevent complications, like infections or secondary surgeries, often related to the implantation of permanent devices. Iron and magnesium alloys were extensively studied as candidates for absorbable medical applications, but they generally failed to provide a desirable mechanical performance and corrosion characteristics in the physiological environment. Zinc was introduced in the last decade as a potential implant material after showing outstanding biocompatibility and biodegradability. This review summarizes the research advances to date and provides a thorough discussion of the future challenges of absorbable zinc alloys to satisfy the demanding clinical benchmarks for absorbable medical applications. Their biocompatibility, mechanical, and corrosion aspects, both in vitro and in vivo , are comprehensively reviewed and assessed accordingly. [ABSTRACT FROM AUTHOR]

Y, (Y + Nd), and (Y + Ca) multi-microalloying, which has potential to mediate the grain growth and texture evolution, played an important role in the mechanical properties of the studied extruded AZ80 sheet. Quasi-in-situ electron backscattered diffraction results revealed that grain boundary migration and grain rotation simultaneously occurred during the grain growth. All these three microalloying combinations effectively lowered the grain growth rate. In particular, the AZ80 + 0.2Y+0.15Ca maintained the lowest growth rate and the most uniform fine grain structure. The rare-earth (RE) texture components, which temporarily formed in AZ80 + 0.2Y and AZ80 + 0.1Y+0.1Nd, weakened their basal texture intensity. In contrast, continuously enhanced basal texture, accompanied by grain growth, dominated the texture evolution in AZ80 + 0.2Y+0.15Ca. As a result, all microalloyed combinations exhibited lower Vickers hardness than that of AZ80. The microalloying also reduced the hardness anisotropy of the sheets. • (Y + Ca) microalloying dramatically lowers the grain growth rate and homogenizes grain structure in AZ80. • Preferred crystal orientation for the grown grains was prevalent in Y or (Y + Nd) microalloyed AZ80 sheets. • Enhanced basal texture accompanied by grain growth and dominated the annealing texture evolution in AZ80 + 0.2Y+0.15Ca. • The multi-microalloying reduced the hardness anisotropy and degraded the hardness of AZ80 sheets. [ABSTRACT FROM AUTHOR]

Abstract: Slip transfer across the α/β interface was investigated in the near-α titanium alloy Ti–5Al–2.5Sn (wt.%). Globular β-phase grains, located primarily at α-phase grain boundaries, enabled the investigation of the orientation relationship between the α and β phases in the case of a general equiaxed microstructure. Active deformation systems were identified using electron backscattered diffraction (EBSD) supported by plane trace analysis. Information from the plane trace analysis was used to assess a number of metrics that could correlate with α/β slip transfer including: Schmid factors, the angle between slip plane normals (ψ), the angle between active Burgers’ vectors (κ), and the α(0001)/β{110} misorientation angle. From an analysis of 36 β grains, 15 α/β boundaries were found to exhibit the planar α(0001)/β{110} Burgers’ orientation relationship. The α phase, which dominated the microstructure, tended to exhibit slip traces for high global Schmid factor slip systems, including prism, basal, and pyramidal slip planes. When the neighboring β grain was oriented favorably for slip, i.e. exhibited a high Schmid factor, slip transfer was more likely across the α/β interface compared to when the neighboring β phase was not favorably oriented for slip. The alignment between the Burgers’ vectors in the α and β phases was not well correlated with slip across the α/β interface. Furthermore, the boundaries having the α(0001)/β{110} orientation relationship were not necessarily favorable for α/β slip transfer. [Copyright &y& Elsevier]

Processing of metal hybrid nanocomposites have emerged in the recent years by means of solid-state reactions through severe plastic deformation techniques, resulting in heterogenous microstructures and mechanical properties. Despite the increased scientific interest in these unusual materials, little is known regarding their comparative attributes with respect to a homogeneous material having equivalent nominal composition. This work provides a direct comparison of the microstructure and the hardness evolution between a Zn–3Mg (wt.%) alloy and its hybrid counterpart, after high-pressure torsion (HPT) and after HPT followed by a post-deformation annealing (PDA) treatment. Experimental results indicate that both the alloy and the hybrid reach a similar level of grain refinement after HPT processing, however, grain growth follows different trends after PDA. The HPT-processed alloy exhibits clusters of Mg 2 Zn 11 nanocrystalline domains that coalesce into coarser grains maintaining a unimodal GS distribution after PDA. On the other hand, the hybrid after PDA displays a multimodal GS distribution consisting of ultrafine Mg-rich grains containing MgZn 2 and Mg 2 Zn 11 nanoscale intermetallics, in a matrix of coarser dislocation-free Zn grains. These observations were supported by kernel average misorientation (KAM) maps and pole figures obtained through electron backscattered diffraction (EBSD) analysis. • Microstructural evolution is compared between a HPT-processed alloy and its hybrid counterpart. • Heterostructured Zn–Mg hybrid is synthesized via HPT followed by post-deformation annealing (PDA). • Nanocrystalline domains coalesced into coarser grains in the HPT alloy upon PDA. • In-situ precipitation of Mg 2 Zn 11 and MgZn 2 intermetallics ocurred in the hybrid during HPT. • Hardness values and hardness heterogeneity increased after PDA in both the alloy and the hybrid. [ABSTRACT FROM AUTHOR]