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Zinc-rich coatings (ZRCs) are widely used as primers to protect steel. However, their corrosion resistance is limited. Although the addition of graphene oxide (GO) can enhance anticorrosion efficiency, GO tends to agglomerate in ZRCs and spreads in a disordered manner because of its high surface energy. This weakens the ability of GO to prevent the invasion of corrosive media into substrates. In this study, magnetized reduced GO (rGO) was synthesized using rGO with nanoscale iron powder. The magnetized rGO powder was then incorporated into waterborne inorganic ZRCs and placed in a uniform magnetic field. The magnetized rGO powder within the coatings aligned parallel to the substrate instead of exhibiting disordered distribution. This behavior clearly increased the barrier and cathodic protection abilities of the coatings. Results indicate that when 0.1 wt% magnetized rGO was added, the compactness of the coatings was substantially enhanced and the cathodic protection time at inscribed areas increased to 192 h. By contrast, the cathodic protection time of the magnetized rGO free ZRCs was only 96 h. The excellent corrosion assistance of the magnetized rGO incorporated waterborne inorganic ZRCs was attributed to the good barrier protection effect and electron transmission of the aligned magnetized rGO in the coatings.

The discharge behaviors of AZ31 alloys, modified by the addition of In and Sm elements in conjunction with equal channel angular pressing (ECAP) processing, were systematically explored. The incorporation of In suppressed the formation of cathodic second phases. In contrast, Sm promoted the precipitation process and therefore led to higher microstructure uniformity following ECAP processing. The solid-solution In contributed to the activated dissolution of Mg matrix and the inhibited hydrogen evolution during discharge, while Sm was beneficial for the uniform dissolution and the alleviation of chunk effect. The results indicated that the 12-pass ECAP processed AZ31-In-Sm anode revealed the most enhanced discharge performance with a discharge voltage of 0.889 V and a utilization of 66.94% at 100 mA cm−2. This improvement can be primarily attributed to the combined effects of the decreased precipitations of cathodic phases by In addition and the enhanced microstructure homogeneity by Sm addition, collaborated with significant microstructure refinement.

Micro-alloyed Zn–Mg alloys have attracted extensive attention in the field of medical implant due to their excellent biosafety and moderate degradation rate. The low Mg content could compromise the improvement of strength, therefore, the appropriate rolling process was investigated to enchance strength and inhibit strain softening behavior of Zn-0.06 Mg alloy. The observed changes in microstructures, mechanical properties, and strain softening behavior of the as-cast alloy after three different rolling processing were consistent with those exhibited by the solid-solution alloy. The cold rolled alloys showed excellent strength due to their small average grain size and high initial dislocation density, however, they also exhibited noticeable strain softening behavior. Hot rolling processing can result in coarsening of the grains, reduction in dislocation density and introducing a large number of twins, which inhibited strain softening behavior but also leaded to a decrease in the strength compared with cold rolling. The hot-cold rolling processing can induce the formation of heterostructure, wherein coarse grains encircled fine grains, while high density dislocation regions and low density dislocation regions were uniformly distributed, which effectively inhibited strain softening behavior on the basis of maintaining good mechanical properties.

Abstract Recent advances in surface-patterning techniques of liquid crystals have enabled the precise creation of topological defects, which promise a variety of emergent applications. However, the manipulation and application of these defects remain limited. Here, we harness the moiré effect to engineer topological defects in patterned nematic liquid crystal cells. Specifically, we combine simulation and experiment to examine a nematic cell confined between two substrates of periodic surface anchoring patterns; by rotating one surface against the other, we observe a rich variety of highly tunable, novel topological defects. These defects are shown to guide the three-dimensional self-assembly of colloids, which can conversely impact defects by preventing the self-annihilation of loop-defects through jamming. Finally, we demonstrate that certain nematic moiré cells can engender arbitrary shapes represented by defect regions. As such, the proposed simple twist method enables the design and tuning of mesoscopic structures in liquid crystals, facilitating applications including defect-directed self-assembly, material transport, micro-reactors, photonic devices, and anti-counterfeiting materials.

Fused Deposition Modeling (FDM), a widely-utilized additive manufacturing (AM) technology, has found significant favor among automotive manufacturers. Polypropylene (PP) compound is extensively employed in the production of automotive parts due to its superior mechanical properties and formability. However, aiming at the problem of poor dimensional accuracy of pure PP parts, the quality of products can be enhanced by optimizing the combination of processing parameters. In this paper, the dimensional accuracy of 3D-printed components made from pure PP material is investigated. Key influencing factors such as infill percentage, infill pattern, layer thickness, and extrusion temperature are considered. To gain a deeper understanding, fluid simulation is conducted, and mathematical models are established to correlate processing parameters with dimensional accuracy. Furthermore, the Taguchi's experiments are designed and the experimental data are subjected to rigorous Signal-to-Noise ratio and ANOVA analyses. Within the experimental range, the lower extrusion temperature, infill percentage and layer thickness yield the best dimensional accuracy. Considering the influence factors of X, Y and Z directions, the optimal processing parameters for PP prints using screw extrusion 3D printers are determined as follows: an extrusion temperature of 210 °C, an infill percentage of 40 %, a layer thickness of 0.3 mm, and a concentric circle infill pattern. This study provides reference value for the subsequent improvement of the dimensional accuracy of the printed parts.

The aging precipitated phases are of great significance for the strengthening and toughening of Al–Zn–Mg alloys. In this work, pre-precipitating was realized through equal channel angular pressing (ECAP) immediately followed by solid solution treatment at 475 °C for 6 h. Its corresponding strengthening and toughening effect on the room temperature (RT)-rolled Al–6Zn–1Mg alloy was systematically studied. The results indicate that pre-precipitating by ECAP can effectively improve the strength of the RT-rolled Al–6Zn–1Mg alloy and circumvent the strength-ductility trade-off. Microstructure characterization reveals that ECAP induces a large number of microshear bands, which can not only encourage recrystallization but also effectively promote the precipitation of the η′ phase. The synergistic effect of precipitation strengthening and dislocation strengthening contributes to the high strength of Al–6Zn–1Mg alloy, with UTS and YS increasing to ∼522 MPa and ∼400 MPa, respectively. Meanwhile, the ductility remains almost unchanged mainly due to the coordinated grain boundary sliding and the uniform and finely dispersed second phase particles. As a result, the strength-ductility trade-off is effectively avoided. The findings shed some light on optimizing the traditional aging treatment.

In this research, corrosion behavior and discharge capabilities of the AZ61-In alloy experiencing hot rolling process have been discussed in detail. The results reveal that the introduction of indium to magnesium facilitates the dissolution of magnesium by augmenting a quantity of secondary phases, generating less-protective products. The corrosion resistance of AZI plus 50 % rolling reduction is improved attributed to the preferred basal orientation and further recrystallization. Moreover, the average discharge potentials of AZI-50 % can respectively reach −1.551 V and −1.234 V at 10 mA cm−2 and 50 mA cm−2, showing potential for application in seawater activated batteries.

The 7046 aluminum alloy possesses a favorable fatigue property, corrosion resistance and weldability, but its moderate strength and plasticity limit its wider application and development. In the present study, severe plastic deformation (SPD) was applied prior to T6 treatment to significantly enhance the strength and toughness of the 7046 aluminum alloy. The results show that the alloy processed by four passes of equal channel angular pressing (ECAP) at 300 °C prior to T6 treatment exhibits an excellent mechanical performance, achieving an ultimate tensile strength (UTS) and elongation (EL) of 485 MPa and 19%, respectively, which are 18.6% and 375% higher than that of the T6 alloy. The mechanical properties of the alloy are further improved by an additional room temperature (RT) rolling process, resulting in a UTS of 508 MPa and EL of 23.4%, respectively. The increased presence of η′ and Al6Mn phases in the 300°C4P-R80%-T6 and 300°C4P-T6 alloys contributes to a strengthening and toughening enhancement in the SPD-processed T6 alloy. The findings from this work may shed new insights into enhancing the 7046 aluminum alloy.

The effect of adding a small amount of Ag on the microstructure evolution and superplastic properties of Mg-Y-Er-Zn (WEZ612) alloys was systematically studied. The basal texture of the refined WEZ612 alloy produced by equal channel angular pressing was altered to a non-basal structure upon the addition of Ag. Ag addition also refined the grain size and promoted the formation of a large number of nano-14H-long period stacking ordered phases. Using high-resolution transmission electron microscopy, many nano-precipitated phases were detected on the basal plane of the Mg-Y-Er-Zn-1Ag (WEZ612–1Ag) alloy, The nano-precipitated phases on the basal plane improved the thermal stability of the alloy, lowered the deformation activation energy (Q), and improved the stress sensitivity index (m). At 523 K with a strain rate of 10−2 s−1, the Q value of WEZ612 was higher than that of WEZ612–1Ag (299.14 and 128.5 kJ mol−1, respectively). In contrast, the m value of the WEZ612 alloy (0.16) was lower than that of the WEZ612–1Ag alloy (0.46). At 623 K with a tensile rate of 10−2 s−1, the WEZ612 and WEZ612–1Ag alloys were elongated by 182% and 495%, respectively, with the latter exhibiting high-strain-rate and low-temperature superplasticity. The improved superplasticity of the WEZ612-1Ag alloy is attributed to the nano-precipitated phases, which effectively limit the cavity extension during superplastic deformation.

Zn–Ag alloys are recently regarded as highly promising biodegradable materials for medical applications, but they suffer from inferior mechanical properties. In this work, a Zn-0.5Ag-0.08Mg (wt.%) alloy with high strength and ductility was obtained by equal channel angular pressing (ECAP). Zn-0.5Ag-0.08Mg samples were ECAP processed for six different passes (1P, 2P, 3P, 4P, 8P, and 12P) to investigate the effect of ECAP on the microstructure and mechanical properties. Samples processed for 3P, 4P, 8P, and 12P exhibit mechanical properties satisfying the application requirements. The sample processed for 4P possesses the largest ultimate tensile strength (UTS) of 388.1 MPa, accompanied by an excellent elongation (EL) of 45.3%. The sample processed for 12P shows the best EL of 58.3%, along with a high UTS of 332.5 MPa. The high strength is attributed to grain boundary strengthening and dislocation strengthening. The high ductility is closely related to relatively weak texture, grain refinement, and twin boundary suppression.

Zinc alloys have great potential to become a new generation of biodegradable implant materials for biomedical applications due to their moderate corrosion rates. However, the poor mechanical properties restrict the application of pure zinc as biomedical materials. In this study, Zn–0.1Mg–0.02Mn alloy was rolled to different reductions at room temperature. The 80% reduction rolled alloy showed the best mechanical performance with ultimate tensile strength and elongation of 397.7 MPa and 15.9%, respectively, which satisfy the requirement of biomedical implant materials. Grain refinement mainly promoted the strength enhancement with increased rolling reductions. The microstructure evolution reveals that the basal-oriented grains and non-basal-oriented grains had different deformation mechanisms to induce DRX process during rolling. DRX could be directly accelerated in basal-oriented grains by basal slip, while twinning and de-twinning process operate to refine the non-basal-oriented grains.

The pivotal role of lithium (Li) in improving the comprehensive mechanical properties of third-generation Al–Li alloys remains significant even at a low content. However, the strengthening contribution of a low dosage lithium and its combination with different processing methods remain largely unknown. This study aimed to investigate the strengthening effects of room-temperature (RT) equal channel angular pressing (ECAP) and rolling on Al–0.6Li alloy. Microstructural evolution during processing was monitored by optical microscope (OM), scanning electron microscope (SEM), electron backscattered diffraction (EBSD), transmission electron microscope (TEM) and X-ray diffraction (XRD). The results revealed that simultaneous high ultimate tensile strength (UTS, 243 MPa) and yield strength (YS, 210 MPa) of the developed Al–0.6Li alloy were specifically achieved with a combination of RT ECAP and rolling, alongside an elongation (EL) of 9.5%. The gained strength improvement was primarily credited to the excellent fine-grain strengthening, as evidenced by a significant reduction in grain size from 101 μm to 1.47 μm, and dislocation strengthening, which, respectively, contributed to an increase of 91 MPa and 100 MPa in YS. Findings from this study demonstrate that with proper processing technology, the mechanical properties of Al–Li alloys with low Li content can be effectively improved, opening new avenues to develop high-performance Al–Li alloys.

A super-high strength Mg–9Li–1Al (LA91) alloy with ultimate tensile strength (UTS) of 312 MPa and specific strength of ∼215 kNmkg−1 was successfully achieved via a combined processing of multi-pass equal-channel angular pressing (ECAP) with repeated annealing and room temperature (RT) rolling. Significant grain refinement after ECAP led to the formation of ultrafine-grain (UFG) α-Mg phase with grain size of ∼350 nm. Further refinement of the α-Mg grains reaching ∼200 nm was achieved by further repeated annealing and RT-rolling with high dislocation density. The formation of strong basal texture of the α-Mg phase of the combined-processed alloy also contributed to the achieved excellent strength-ductility synergy. The 1 wt% Al (aluminum) in the Mg–Li dual-phase matrix acted as a high-efficient strengthening element, and was the major contributory factor to the 48% improved specific strength of the alloy compared to the UFG Mg–9Li binary alloy in our former study. The Al element distributing throughout the alloy phases without segregation contributed to the enhanced refinement of the α-Mg grains during the combined processing and improved strain-hardening rate during the tension plastic deformation, allowing for the achievement of a high strength of the LA91 alloy.

Alloying rare earth (RE) elements is an effective method to improve corrosion resistance of Mg-Al alloy but excessive RE concentration may aggravate galvanic corrosion. In this study, density functional theory calculations are performed to unravel effects of RE (RE = Sc, Y, Nd) concentration on the galvanic corrosion of Mg-Al alloy from the perspectives of work function and surface energy. The results showed that, when the RE concentration was low, the galvanic corrosion between Mg matrix and Mg17Al12 phase could be alleviated with the increasing of RE concentration. When the RE concentration was high, the precipitated RE phases became cathodes and strongly aggravated galvanic corrosion of Mg matrix. Furthermore, regardless of the change of RE concentration, the effectiveness of alleviating galvanic corrosion in Mg-Al alloy was in the order: Sc > Y > Nd. Possible explanations to experiments were provided and potential strategy to improve corrosion resistance of Mg-Al alloy was also proposed.

Zn–Ag alloys are particularly promising for application as biodegradable implant materials due to their harmless degradation products, suitable degradation rate, and remarkable biocompatibility. Nonetheless, their mechanical properties are generally below the requirements for medical implants. In this work, a bimodal grain structured Zn–0.5Ag–0.2Mg alloy with excellent strength and ductility was achieved through combined equal channel angular pressing (ECAP) and cold rolling (CR), significantly superior to their counterparts obtained through ECAP or CR. Specifically, the ultimate tensile strength (UTS) and elongation (EL) of the alloy are as high as 332 MPa and 63%, respectively, far exceeding the application requirements. In achieving the excellent mechanical properties, a key role is played by hetero-deformation induced (HDI) strengthening. This work may provide practical guidance for developing high-performance Zn alloys.

Material design and preparation based on constructing heterogeneous microstructures can break the conventional performance limitations of fine-grained magnesium alloys. In this study, AZ61 alloys processed via multi-pass equal channel angular pressing (ECAP) were subjected to single-pass rolling (SPR) with increased rolling reductions. The effect of rolling reduction on the formation of heterogeneous microstructure and the mechanical properties of the alloy was investigated. Microstructural examinations revealed that a heterogeneous microstructure was formed in the alloy at varied rolling reductions, but the desired heterostructure with higher fine grain contents could only be achieved at increased rolling reduction. This was mainly due to the fact that the alloy underwent partial dynamic recrystallization (PDRX) under SPR, and PDRX more easily occurred with higher rolling reduction. The tensile test results showed that with increased rolling reduction, the strength of the alloy first increased and then decreased slightly, with the ductility steadily increasing. Improved mechanical properties were achieved in the alloy rolled at increased rolling reductions owing to the heterogeneous microstructure with a greater content of fine grains.

Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys. However, it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity. Herein, a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium, which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating. The multiscale microstructures with nanoscale stacks and microscale spheres on the surface, as well as the through-thickness stearates, lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating.

The Mg17Al12-phase, which is common and important in Mg-Al alloy, has long been regarded as a brittle phase in experiments but theoretical calculations report controversial results. To unravel why theoretical calculations report controversial results and determine whether Mg17Al12 is brittle or ductile, density functional theory calculations on atomic level are performed to investigate mechanic properties of Mg17Al12 without containing alloying elements and without taking the size effect. The results showed that the parameter k-point played critical role in the DFT-based elastic calculations. The convergent G/B ratio of Mg17Al12 was about 0.52, suggesting that the Mg17Al12-phase was theoretically ductile although its ductility was poor. The chemical bonding in Mg17Al12 was the mixture of metallic Mg-Mg bond and covalent Al-Al bond. The advantage of metallic bonding over covalent bonding provided a possible explanation for the ductility of Mg17Al12. Possible reasons for the brittleness of Mg17Al12 in experiments are also discussed.

A warm equal-channel angular pressing (ECAP) procedure was applied to a new Mg–6.5Y–1.2Er–1.6Zn (WEZ612)–0.5Ag alloy with a long-period stacking ordered (LPSO) phase. The microstructure, superplasticity, and deformation mechanism of the WEZ612–0.5Ag alloy were then systematically investigated. Three different precipitation phases formed in the alloy with trace Ag addition, namely LPSO, γ, and nanoprecipitate phases. A remarkable elongation of 726% was attained at 623 K and a strain rate of 0.01 s−1. The strain rate sensitivity index (m) and activation energy (Q) under these deformation conditions were 0.461 and 133.08 kJ mol−1, respectively. These m and Q values confirm that the primary deformation mechanism of the WEZ612–0.5Ag alloy at 623 K was grain boundary sliding assisted by lattice diffusion. The highly stable LPSO phases, γ precipitates, and nanoprecipitates synergistically improved the superplasticity of the alloy by retarding crack propagation and grain growth and by promoting the basal plane slip.

For the purpose of designing high strength and high ductility Zn–Cu–Mg biodegradable alloys, this study systematically investigated the evolutions of CuZn5 and Mg2Zn11 s phases during equal channel angular pressing (ECAP) with gradually increased deformation strains, as well as their impact on the mechanical properties of Zn–1Cu-0.5 Mg and Zn–3Cu-0.5 Mg alloys. The obtained results showed that the as-cast Zn–1Cu-0.5 Mg alloy contained η-Zn matrix and η-Zn + Mg2Zn11 eutectic structure, while the as-cast Zn–3Cu-0.5 Mg alloy is composed of η-Zn matrix, Zn–Mg eutectic structure, and coarse primary CuZn5 phase. Although the primary CuZn5 phase was refined to some extent after ECAP, some large ones remained. The eutectic structure was quickly crushed into ultra-fine Mg2Zn11 particles, and sub-micron CuZn5 precipitates were dynamically precipitated within the matrix of both alloys during ECAP. Moreover, the refined Mg2Zn11 particles and CuZn5 precipitates were not mixed, but formed the η-Zn + Mg2Zn11/η-Zn + CuZn5 bandlike distribution. ECAP simultaneously improved the strength and ductility of two alloys, and the softening behaviors with more ECAP strains were alleviated to some extent with Mg addition. The high strength of ECAP alloys was mainly resulted from the fine grain strengthening, Mg2Zn11 particles strengthening, and hetero deformation-induced (HDI) strengthening by the bimodal grain size distribution and bandlike distribution. Improvement in softening resistance should be ascribed to the formation of ultra-fine Mg2Zn11 particles which are effective to promote the aggregation and proliferation of dislocations.

Abstract Background Transarterial chemoembolization (TACE) has been shown to prolong survival in patients with unresectable hepatocellular carcinoma (HCC); however, the long-term survival remains dismal. Targeting macrophage and neutrophil infiltration is a promising strategy. The CCL2/CCR2 and CXCLs/CXCR2 axes are required for recruitment of macrophages and neutrophils, respectively, in HCC. We investigated the feasibility of CCL2/CCR2 and CXCLs/CXCR2 as therapeutic targets in combination with TACE for treating HCC. Methods Expression of CCL2/CCR2 and CXCLs/CXCR2 was analyzed in the primary rat HCC model and one HCC cohort. The relationship between expression levels, neutrophil and macrophage infiltration, hepatocarcinogenesis progression in the rat model, and survival of HCC patients was assessed. The anti-tumor effects of blocking the CCL2/CCR2 and CXCLs/CXCR2 axes by CCR2 and CXCR2 antagonists in combination with TACE were evaluated in HCC rats. The numbers of macrophages, neutrophils, and hepatic progenitor cells were further determined to explore the underlying mechanisms. Results High macrophage and neutrophil infiltration and CXCL8 expression were associated with poor prognosis in the TCGA liver cancer dataset. High expression of CCL2/CCR2 and CXCL8/CXCR2 in clinical HCC specimens was associated with reduced survival. Expression of CCL2/CCR2 and CXCL1/CXCR2 was correlated with hepatocarcinogenesis progression in the primary rat HCC model. Blockade of CCL2/CCR2 and CXCLs/CXCR2 enhanced the anti-tumor effect of TACE treatment in this model. Blocking the CCL2/CCR2 and CXCLs/CXCR2 axes with CCR2 and CXCR2 antagonists in TACE-treated rats reduced macrophage and neutrophil infiltration and hepatic progenitor cell activation and thus overcame TACE resistance in HCC. Conclusions The results demonstrate the translational potential of immunotherapy targeting the CCL2/CCR2 and CXCLs/CXCR2 axes in combination with TACE therapy for the treatment of HCC.

As the lightest metallic structural materials with excellent damping capacity, good castability, and high specific strength, Mg alloys have huge potential for application in many industries including aircraft, automobile, and rail traffic. However, the strength of Mg alloys generally falls below the application benchmark and the development of high-strength Mg alloys relies on the addition of rare earth (RE) elements, which raises their cost and limits their application. Mg–Sn based alloys are promising age-hardenable RE-free Mg alloys which exhibit the potential of replacing those containing RE elements and becoming heat-resistant high-strength Mg alloys. Microstructure and mechanical properties of Mg–Sn based alloys have attracted enormous research interest over the past two decades. A comprehensive review of recent advances in this field is beneficial for their development, but such a review is still unavailable. This paper reviews recent progress of Mg–Sn based alloys from the perspective of the relationship between aging response and mechanical performance, striving to provide guidance for the development of high-performance Mg–Sn based alloys. Several key aspects are discussed including aging response, room temperature strength and ductility, and tension-compression yield asymmetry.

Abstract The malignant transformation of hepatic progenitor cells (HPCs) in the inflammatory microenvironment is the root cause of hepatocarcinogenesis. However, the potential molecular mechanisms are still elusive. The HPCs subgroup is identified by single‐cell RNA (scRNA) sequencing and the phenotype of HPCs is investigated in the primary HCC model. Bulk RNA sequencing (RNA‐seq) and proteomic analyses are also performed on HPC‐derived organoids. It is found that tumors are formed from HPCs in peritumor tissue at the 16th week in a HCC model. Furthermore, it is confirmed that the macrophage‐derived TWEAK/Fn14 promoted the expression of inhibitor of differentiation‐1 (ID1) in HPCs via NF‐κB signaling and a high level of ID1 induced aberrant differentiation of HPCs. Mechanistically, ID1 suppressed differentiation and promoted proliferation in HPCs through the inhibition of HNF4α and Rap1GAP transcriptions. Finally, scRNA sequencing of HCC patients and investigation of clinical specimens also verified that the expression of ID1 is correlated with aberrant differentiation of HPCs into cancer stem cells, patients with high levels of ID1 in HPCs showed a poorer prognosis. This study provides important intervention targets and a theoretical basis for the clinical diagnosis and treatment of HCC.

Unique Mg-RE (rare earth) alloys with long-period stacking ordered (LPSO) structures have attracted extensive attention for their excellent mechanical properties and bright prospects. Thus it is urgent to improve their corrosion resistance simultaneously. The present work focused on the improvement of microstructure and corrosion behaviours in new Mg-2.2Y-1.1Zn-0.4Mn (wt. %) alloys with mixed LPSO phases through warm equal-channel angular pressing (ECAP) integrated with prior solution treatment (ST). The results show that the multi-pass ECAP process optimizes the grain size and distribution of mixed LPSO phases, which improves the corrosion resistance of the alloy. During the integrated ECAP processing, the massive 18 R phase was broken from 100 μm (as-cast) to 5–8 μm (12 passes), and the precipitated 14H phase was more uniformly distributed in the fined α-Mg matrix. Accordingly, the corrosion resistance of the LPSO-containing samples from 0 to 8 ECAP passes increased for a more uniform and more refined structure. In contrast, the corrosion resistance improvement of the 12-pass ECAP one was reduced slightly for weakened 18 R barriers.

Corrosion behavior of ultrafine-grained (UFG) pure titanium was studied in simulated seawater at high temperature to increase the probability for marine devices. The UFG Ti was prepared by equal channel angular pressing. The grain size was around 450 nm. The results showed that the corrosion current density of UFG Ti was lower than coarse-grained (CG) Ti in 3.5%NaCl solution at 80 °C, and the UFG Ti could resist pitting corrosion preferably. The basal texture of UFG Ti was stronger and the content fraction of TiO2 in the passive film was higher than CG Ti. The enhanced corrosion performance of UFG Ti at high temperature was attributed to the comprehensive impact of grain size, texture and passive film.

Abstract Background Hamartoma refers to the excessive focal growth of cells and tissues in organs, which is between malformation and benign tumor. Hamartomas are commonly seen in the lung, but rare in the retroperitoneum. Main text Angiomyolipoma was also called hamartoma in the early years. Hamartoma was not separated from the concept of angiomyolipoma until perivascular epithelioid cells were found in angiomyolipoma. We reported a case of retroperitoneal hamartoma, which was suspected to be angiomyolipoma in the initial imaging findings and pathological frozen section, but the paraffin section was finally diagnosed as hamartoma. Due to the fusion of the tumor with the right psoas major muscle, it may need to be cut off for complete resection of tumor, which may damage the sacrococcygeal nerve and affect the postoperative activity function, so the tumor was just partially removed. After 6 and 22 months of follow-up, the patient was in good condition. CT re-examinations showed that the epibiotic right retroperitoneal mass size was 40 × 42 × 72 mm3 (6 months, length × width × height) and 40 × 45 × 81 mm3 (22 months, length × width × height). We describe this case and review the literature. Conclusions In conclusion, retroperitoneal hamartoma is rare and difficult to differentiate from angiomyolipoma, in which perivascular epithelial cells could be found on pathological paraffin sections.

Abstract Liver cancer arises from the evolutionary selection of the dynamic tumor microenvironment (TME), in which the tumor cell generally becomes more heterogeneous; however, the mechanisms of TME-mediated transcriptional diversity of liver cancer remain unclear. Here, we assess transcriptional diversity in 15 liver cancer patients by single-cell transcriptome analysis and observe transcriptional diversity of tumor cells is associated with stemness in liver cancer patients. Tumor-associated fibroblast (TAF), as a potential driving force behind the heterogeneity in tumor cells within and between tumors, was predicted to interact with high heterogeneous tumor cells via COL1A1-ITGA2. Moreover, COL1A1-mediated YAP-signaling activation might be the mechanistic link between TAF and tumor cells with increased transcriptional diversity. Strikingly, the levels of COL1A1, ITGA2, and YAP are associated with morphological heterogeneity and poor overall survival of liver cancer patients. Beyond providing a potential mechanistic link between the TME and heterogeneous tumor cells, this study establishes that collagen-stimulated YAP activation is associates with transcriptional diversity in tumor cells by upregulating stemness, providing a theoretical basis for individualized treatment targets.

With a suitable degradation rate, fully bioresorbable degradation products, and excellent biocompatibility, Zn and its alloys are regarded as the most promising biodegradable metallic materials for clinical applications. However, their strength and ductility are generally below the mechanical benchmark for biodegradable implants, such as bone fixtures and stents, which restrict wider applications. Over the past decade, enormous efforts have been dedicated to improving the mechanical performance of Zn alloys, which greatly advance our understanding of Zn alloy development. This review highlights recent progress of biodegradable Zn alloys from the perspective of strengthening and toughening, with an emphasis on the relationship between the microstructure and the mechanical properties of the four major Zn alloy systems: Zn–Mg, Zn–Li, Zn–Mn, and Zn–Cu based alloys. The dominant mechanisms for high strength and high ductility of these alloys are elaborated. Finally, the future challenges and research directions of the field are outlined. This review strives for provide guidance for the future development of high-performance bioresorbable Zn alloys.

A homogeneously ultrafine-grained (UFG) Cu-38 Zn alloy with an average grain size of 0.64 μm is successfully fabricated by equal channel angular processing (ECAP), which exhibits a significantly enhanced strength-ductility synergy. The strength enhancement can be attributed to grain refinement and dislocation strengthening. After annealing the ECAP processed alloy at 300 °C for 30 min, a further enhanced strength with almost unchanged ductility was achieved. This unusual annealing strengthens is associated with the solute/impurity segregation and precipitations inside the grains.

Membranes of guided bone regeneration (GBR) are widely used in oral implant surgeries. This study successfully developed a new GBR membrane, hydroxyapatite (HA) coating, on Mg–2Zn–Mn–Ca–Ce alloy substrates via a hydrothermal technique. The features of the HA coatings were investigated by complementary characterization methods (SEM, XRD, EDS, and static contact angle). The in-vitro degradation behavior and biocompatibility of HA-coated and bare Mg–2Zn–Mn–Ca–Ce alloys were analyzed in detail. The HA coatings exhibited porous outer surface and compact inner layer, outstanding hydrophilicity, and thus significantly improved the anticorrosion/biodegradability of the Mg alloy substrate in Hank's solution. Moreover, the results of CCK-8 assays and cell adhesion tests suggested that HA-coated samples could further promote cell adhesion and proliferation. HA-coated Mg–2Zn–Mn–Ca–Ce alloys have good biodegradation behavior and biocompatibility, indicating great potential as a GBR membrane material.

Long-period stacked ordered (LPSO) Mg–Y–Zn alloys have shown great medical prospects. To explore the impact of LPSO phase evolution on mechanical properties, a new biomedical Mg-2.2Y-1.1Zn-0.4Mn (wt.%) alloy prepared by solution treatment plus equal-channel angular pressing (ECAP) was systematically investigated. The results indicate that massive 18R LPSO networks along α-Mg grain boundaries are disintegrated during solution treatment of the as-cast alloy, whereas 14H lamellas are precipitated in α-Mg grains. Following a similar dispersion of 14H precipitated phases, the remnant 18R network phase was gradually extended, broken, and refined throughout the subsequent multi-pass ECAP process. The refined LPSO phases promote dynamic recrystallization (DRX) during the severe deformation process and improve mechanical properties of the obtained fine-grained alloy. After 773K solution treatment for 10h plus 693K ECAP for 12 passes, the biomedical alloy with co-existing 18R and 14H LSPO phases shows excellent mechanical properties with an ultimate tensile strength of 326.6 MPa and elongation of 14.5 percent.

In this work, the effects of Mg content on the microstructure evolution, mechanical properties, and corrosion behavior of as-cast Zn-xMg (x = 0.1, 0.3, 0.5, 1.0, 1.5, and 3.0, wt.%) binary alloys were investigated. The microstructure of as-cast alloys is composed of α-Zn matrix and a ternary eutectic phase (α-Zn + Mg2Zn11+MgZn2). With the increase of Mg content, the average grain size of the alloys decreases from 104 μm to 11 μm while the volume fraction of eutectic structure increases from 3% to 84%, resulting in the improvement of tensile strength. In vitro immersion tests demonstrate that the corrosion rate decreases to a minimum value of 0.086 mm y−1 as Mg content increases from 0.1 to 0.3, followed by an increasing trend with the further increase of Mg content. The variation of corrosion rate with Mg content originates from the competition between the positive effect of grain refinement and the negative effective of eutectic volume fraction increment. Zn-0.3 Mg alloy has the optimal corrosion resistance because of the dominant role of grain refinement induced corrosion resistance enhancement. In addition, the corrosion mechanism varies from localized pitting to a more uniform corrosion as Mg content rises.

The potential of rotary-die equal channel angular pressing (RD-ECAP) for improving the corrosion performance of commercially pure titanium (CP-Ti) in a 3.5% NaCl solution was studied. The microstructure and texture of CP-Ti were evaluated and linked to the corrosion performance. The results showed that as the number of RD-ECAP passes increased, the grains became more refined. A linear correlation of the corrosion current density and grain size was revealed. In addition, strong basal texture was formed after one pass of RD-ECAP, and the texture coefficient remained basically constant with increase in the number of passes. The 4-pass RD-ECAP processed samples with the smallest grain size and strong basal texture exhibited the best corrosion behavior.

In this paper, high-strength ultrafine-grained (UFG) pure aluminum (Al) was successfully achieved via a two-step processing route including room-temperature ECAP process for continuously 16 passes and post liquid nitrogen cryo-rolling for 50% reduction. The two-step processing route was observed to produce ultrafine grains with an average grain size of 0.98 μm and has obvious advantages for the preparation of high-strength pure Al in terms of the strength-ductility synergistic effect, which endows the pure Al excellent UTS value of 180 MPa, good Ef of 17.7% and a very high increase ratio (about 84%) of strength. The high strength was mainly attributed to the outstanding fine-grain strengthening provided by the combination of large-pass ECAP and cryo-rolling. In addition, the better uniform elongation of ECAP-rolled pure Al than ECAPed one was primarily dictated by the enhanced strain hardening capacity and the elongated grain shape.

In this study, SiCp/AZ91 composites with enhanced mechanical properties was successfully obtained by a combined process route of equal channel angular pressing (ECAP) and rolling. The effect of ECAP and rolling on the microstructure and mechanical properties of SiCp/AZ91 composites were investigated by comparative analysis. Results showed that the high-pass ECAP process effectively refined the matrix grains and dispersed the SiCp, which gave rise to the final formation of homogenous microstructure in the rolled plate. A non-basal texture with high Schmidt factors was formed by ECAP process, while after rolling it turned into basal texture with relatively lower Schmidt factors. The SiCp/AZ91 composite obtained by the combined process method exhibited superior mechanical properties (yield strength of ∼348 MPa, ultimate strength of ∼411 MPa) and improved ductility (elongation of ∼6.3%) than the composite singly processed by rolling. The enhanced mechanical properties should be contributed to the homogenized microstructure with refined grains, uniformly distributed SiCp, accumulated dislocations and transferred texture.

Flow behavior of three near eutectic Al–Si alloys with the same chemical composition but different average eutectic Si sizes (A1, 1.7 μm; A2, 4.4 μm; A3, 8.2 μm) was investigated by isothermal compression tests conducted on a Gleeble-3500 thermal simulator under four different temperatures (350 °C, 400 °C, 450 °C, and 500 °C) and four different strain rates (0.01 s−1, 0.1 s−1, 1 s−1, and 5 s−1), with a focus on the effect of eutectic Si size. Not only the flow behavior but also the processing map of near eutectic Al–Si alloys are affected by eutectic Si size. The overall trends of the flow stress–strain curves of the three alloys are similar, but their steady flow stresses σs are different: A1 alloy has the largest σs, followed by that of A3. Strain-compensated constitutive equations in the hyperbolic sine form were constructed to describe the flow stress behavior of the three alloys. Materials constants of the constitutive equations depend on eutectic Si size. The processing maps of the three alloys exhibit different characteristics. The instability domain of A2 alloy is restricted to strain rates larger than about 0.4 s−1, in contrast to the case of A1 and A3 alloys in which the instability domain occurs at both low and high strain rates. The results presented in this study indicate that eutectic Si size is an indispensable factor to be considered when dealing with the hot working of Al–Si alloys.

Laparoscopic cholecystectomy (LC) has been widely used by surgeons. However, the missed diagnosis of intraperitoneal malignant tumor may occur. If the malignancy exists, the changes of the abdominal environment or the laparoscopic operation might brought the cancer cells to abdominal cavity or wall, to more extreme condition, will be located in the navel, which is known as Sister Mary Joseph's nodule(SMJN).A 63-year-old female who had undergone cholecystectomy and choledocholithotomy ten months ago was hospitalized for upper abdominal pain. Laboratory examination indicated that most of tumor markers were increased. CT revealed a progressively enhanced mass around the left lobe bile duct, multiple enlarged lymph nodes in the abdominal cavity and nodular lesions were found under the costal margin of the right side of abdominal wall and the umbilicus. Biopsy of the nodules under the original surgical scar showed middle differentiated adenocarcinoma.In laparoscopic cholecystectomy, surgeons should not only focus on the local lesions, but also look around other the tissues and organs to avoid missing the abdominal malignant tumor. When atypical symptoms or abnormalities have been found pre-operation, all abdominal organs should be evaluated in detail to avoid missed diagnosis of potential malignant tumors. On the other hand, when there is a nodule in the umbilicus, all organs in abdomen should be examined to find the potential malignant tumor. Finally, multiple cholelithiasis in the left lobe of the liver should be regarded as a high risk factor for cholangiocarcinoma.

A novel method was developed via the continuous refinement of grains to prepare an Mg–6.5Y–1.2Er–1.6Zn (wt.%) alloy with a ductility of 35% and an ultimate tensile strength of 377 MPa. It involved the use of a 32-pass equal-channel angular pressing process. The strength and ductility of the obtained magnesium alloy after the rapid processing were improved by 188.5% and 700%, respectively, compared with an as-cast alloy. These improvements are attributed to the refined 14H-LPSO, uniform distribution of the spheroidized second phase, and a large number of dynamic recrystallized grains.

Abstract Background The liver possesses a powerful regeneration ability, which is correlated with the stemness of hepatocytes in the portal vein (PV). However, the mechanism underlying the maintenance of hepatocyte stemness has not been elucidated. Here, we hypothesized that high levels of lipopolysaccharide from the portal vein might maintain the stemness of hepatocytes in the PV area. Methods First, we examined the location of hepatic stem cells and the concentration of lipopolysaccharide (LPS) in the portal vein and inferior vena cava. Then, we assessed the effect of LPS on stemness maintenance in mice by using antibiotics to eliminate LPS and knocking out the LPS receptor, TLR4. In vitro, the effect of LPS on the stemness of hepatocytes was investigated by colony and sphere formation assays and assessment of pluripotent and stem cell marker expression. Furthermore, we studied the mechanism by which LPS regulates the stemness of hepatocytes. Finally, we ligated the portal vein branch to further verify the effect of LPS. Results We found that a high level of LPS from the portal vein was correlated with the location of hepatic stem cells in the PV area, and elimination of LPS by antibiotics inhibited the expression of the stemness marker. LPS promoted colony and sphere formation and induced the upregulation of pluripotent and stem cell markers in AML12 cells. Furthermore, in the reprogramming medium, LPS facilitated the dedifferentiation of mature hepatocytes into hepatic progenitor-like cells, which exhibited a bipotent differentiation capacity in vivo and in vitro. Mechanistically, LPS bound TLR4 to regulate stemness of hepatocytes via the activation of YAP1 signaling, and blockade of YAP1 abolished the LPS-induced cell stemness and upregulation of pluripotent markers. Conclusions Our study implies a correlation between LPS/TLR4/YAP1 signaling and cell stemness, and LPS was shown to be involved in stemness maintenance of hepatocytes in the PV area. LPS might be used to induce the dedifferentiation of mature hepatocytes into progenitor-like cells for repair of liver injury.

The effects of Ca addition and equal channel angular pressing (ECAP) on the microstructure evolution and discharge properties of AZ31-1.0Ca alloy were investigated to develop high-performance anodes for seawater-activated battery. Microscopic observations show that the net-like (Mg, Al)2Ca phase replaces the Mg17Al12 phase and distributes along grain boundaries in AZ31-1.0Ca alloy. 12-pass ECAP effectively refines the grains and crushes the (Mg, Al)2Ca phase into fine particles. The discharge measurements reveal that the 12-pass ECAP processed AZ31-1.0Ca anode exhibits desirable discharge properties with the largest power density of 88.1 mW cm−2 and the highest anodic efficiency of 63.3% at 100 mA cm−2, which are 25.0% and 13.6% higher than that of AZ31 anode, respectively. The enhanced discharge performances can be attributed to the modified microstructure with refined grains, fragmented and dynamically precipitated (Mg, Al)2Ca particles.

Programmable soft materials have shown applications in artificial muscles, soft robotics, flexible electronics, and biomedicines due to their adaptive structural transformations. As an ordered soft material, directional shape changes of liquid crystal elastomer (LCE) can be easily achieved via external stimuli thanks to its anisotropic elasticity. However, harnessing the interplay between molecular ordering, geometry, and shape morphing in this anisotropic material to create programmable and complex shape changes remains a challenge. Here, by integrating the concepts of kirigami or Chinese paper cutting “JianZhi” in the light‐actuated LCE encoded with controlled molecular orientations, various complex 3D shape morphing behaviors are demonstrated. Versatile combinations of fundamental shape changes such as bending, folding, twisting, and rolling are enabled by fine‐tuning the molecular orientations and geometries in the monolithic LCE kirigami. Furthermore, various functions such as fluttering of the Chinese crane bird “QianZhiHe,” arbitrary directional locomotion in the annulus and linear locomotion in the complex Chinese character are also realized. These complex, fast‐response, untethered, remote, reversible, and programmable shape morphologies actuated in a monolith of LCE kirigami will open opportunities in soft robotics and smart materials.

Mg–Y–Zn alloys with long period stacking ordered (LPSO) structure have received much attention recently and exhibit great potential in applications such as automotive, aerospace and in bio-medical fields. This paper aimed to investigate the effect of different phase constitution of LPSO structures on corrosion rate of bio-medical Mg–Y–Zn alloys. The results showed that as-cast Mg98.5Y1Zn0.5 alloys containing only 18R structure exhibited the highest corrosion resistance with the corrosion rate of 2.78 mm/year. The precipitation of 14H lamellas within α-Mg grains during solid solution treatment introduced the crystallographic orientation corrosion by accelerating micro-galvanic corrosion. The increase of 18R/14H interfaces deteriorated the corrosion resistance, and the grain boundaries also suffered from severe electrochemical dissolution. This work suggested that Mg–Y–Zn alloys with single LPSO structure (either 18R or 14H) exhibited better corrosion resistance than alloys with co-existence 18R and 14H LPSO structures.

This study reports a detailed investigation of the deformation behavior and microstructural evolution of a novel ultra-low carbon Cr-Mo alloyed dual-phase steel rebar aimed for marine applications. The rebar matrix consists of the lamellar ferrite/bainite dual phases with the lamellar interfaces along the rolling direction. The soft ferrite phase is composed of larger grains with a low dislocation density, while the hard bainite phase is composed of finer grains with a much higher dislocation density. By comparing the strain hardening behavior from different sites at the rebar with varying ferrite and bainite volume fractions, it shows that the hetero-deformation induced (HDI) hardening is strong and dominates the overall work hardening behavior in the early stage of plastic deformation by prevailing over the conventional sum-up of contribution of each phase alone. In this stage, the plastic deformation of ferrite was constrained by the disproportionally-strained, neighboring bainite, creating the accumulation of geometrically necessary dislocations (GNDs) at the phase interface and the long-range HDI stress. The results also reinforce the understanding of deformation behavior of dual-phase steels, especially around the role of HDI stress and hardening.

A high strength and toughness Zn-Mg-Mn alloy with ultimate tensile strength of 358 MPa and fracture elongation of 23.5% was successfully prepared by 12-pass equal channel angular pressing. The multi-interactions between dislocations and refined microstructure including grain boundaries, eutectic structure, MnZn13 particles and dislocation arrays contributed to strengthening of the alloy.

It is challenging to develop Mg alloys with high strength-ductility synergy and isotropic mechanical properties. An industrial-scale ultrafine-grained (UFG) Mg-10.6Gd-2Ag wt. % alloy with excellent strength-ductility synergy and near-isotropic mechanical behavior was made by an industrial-scale rotary die equal channel angular pressing (RD-ECAP). The microstructure of the UFG alloy involves the primarily submicron α-Mg grains with an average grain size of 760.5 nm and the high-density submicron β phase (Mg5Gd) precipitates (267.8 nm). Room temperature tensile tests results reveal that the UFG alloy exhibits an over three times tensile yield strength, near two times ultimate tensile strength, and more than one and a half times elongation along three orthogonal test directions than the as-cast Mg alloy. The improvement of strength is linked to the effect of the grain boundary strengthening as well as the precipitation strengthening. The enhanced ductility is ascribed to the ultrafine grains with low dislocation density, which provide a degree of dislocation storage capacity and facilitates multiple potential deformation modes. The near-isotropic mechanical behavior stems from the weak texture and multiple deformation modes.

In this study, the fragmentation process of 18R long period stacking ordered (LPSO) phase was investigated by comparing the microstructure of as-cast Mg97Y2Zn1 (at%) alloy and 32-pass equal channel angular pressing (ECAP) processed alloy. Results show that two fragmentation modes occurred either singly or in combination during ECAP, i.e., delamination of 18R phase parallel to its basal plane and rupture of 18R perpendicular to its basal plane. Due to these two modes of fragmentation, fine LPSO laths and particles, as well as tiny dynamic recrystallization (DRX) grains were generated in the ECAP alloy, which contributed to its moderate strength and good ductility. In addition, both as-cast and ECAP alloys were subjected to hot rolling to explore the differences of LPSO morphology on rollability of the alloys. The rollability of as-cast alloy was very poor because the coarse microstructure was easy to entangle dislocations and generate microcracks during rolling. However, the rollability of ECAP alloy was significantly improved owing to the additional fragmentation action of band-shaped and kinked LPSO phases, as well as dislocations pinned by LPSO particles or coordinated by more boundaries from fine LPSO particles and DRX grains. Compared with ECAP alloy, the ECAP-rolled alloy exhibited increased strength and moderate ductility with ultimate tensile strength of 384 MPa and fracture elongation of 8.1%.

In the present work, AZ91 alloy was successfully processed by equal channel angular pressing (ECAP) for up to 16 passes and rolling (R) for multiple passes with a total reduction of 75% in addition to a combination method with ECAP plus rolling (ECAP+R). The effects of various processes (ECAP, R and ECAP+R) on microstructure evolution were analyzed and the influence of ECAP process on the rolling performance was examined. The result shows that ECAP contributed to a homogenous grain structure and formed a texture with higher Schmidt factors that was easy for rolling. A plate with smoother surface and reduced edge cracks was observed in the ECAP+R process than in the single R process. Although the microstructure of the alloy was similar after ECAP+R and R process, the sample of ECAP+R was more refined and had stronger second phase precipitation than the sample of R, which resulted in better rolling characteristics, along with the external surfaces. Keywords: AZ91 alloy, ECAP and rolling, “ECAP-modified” structure, Second phase precipitation, Texture

To reduce carbon emission and achieve carbon neutrality, deep geothermal energy has been widely extracted for building heating purpose. In recent years, deep borehole heat exchanger (DBHE) heating system has gained more attention, especially in densely populated urban areas in Weihe Basin, northern China. The long-term performance and the economic feasibility are essential for the system application. In this work, the DBHE model implemented in OpenGeoSys software is verified against an analytical solution and a comprehensive economic analysis approach is further proposed. Then the short-term thermal performance tests are conducted to obtain the tentative heat extraction capacity for long-term simulation. The long-term simulations are further performed with the heat pump unit under the adjusted tentative heat extraction rate imposed on the DBHE. Finally, a comprehensive economic analysis is applied to the DBHE heating system over 15 heating seasons. Results show that the minimum coefficient of performance value of the heat pump is 4.74 over the operation of 15 heating seasons. With the increase of depth for the DBHE, the total electricity consumption of heat pumps and circulation pumps has a prominent promotion. With the comprehensive approach of economic analysis, the depth of 2,600 m has the lowest levelized cost of total heating amount, which is the best system design for the application in Weihe Basin. The present results are specific to the conditions in Weihe Basin, but the proposed economic analysis approach is generic.

To date, immune checkpoint inhibitors have been successively approved and widely used in clinical cancer treatments, however, the overall response rates are very low and almost all cancer patients eventually progressed to drug resistance, this is mainly due to the intricate tumor microenvironment and immune escape mechanisms of cancer cells. One of the main key mechanisms leading to the evasion of immune attack is the presence of the immunosuppressive microenvironment within tumors. Recently, several studies illustrated that triggering receptor expressed on myeloid cells-2 (TREM2), a transmembrane receptor of the immunoglobulin superfamily, was a crucial pathology-induced immune signaling hub, and it played a vital negative role in antitumor immunity, such as inhibiting the proliferation of T cells. Here, we reviewed the recent advances in the study of TREM2, especially focused on its regulation of tumor-related immune signaling pathways and its role as a novel target in cancer immunotherapy.

In this study, the multi-pass equal channel angular pressing (ECAP) was employed on a high-calcium-content Mg-Al-Ca-Mn alloy to tailor its microstructure and mechanical properties. The obtained results showed that the network-shaped Mg2Ca and (Mg, Al)2Ca eutectic compounds in as-cast alloy were gradually crushed into ultra-fine particles after ECAP, which exhibited a bimodal particle size distribution and most aggregated at original grain boundaries. Dynamic recrystallization (DRX) of α-Mg occurred during hot deformation via a particle stimulated mechanism, and the almost complete DRX with an average grain size around 1.5 µm was obtained after 12p-ECAP. Moreover, abundant nano-sized acicular and spherical precipitates were dynamically precipitated within α-Mg grains during ECAP. Tensile test results indicated that the maximum strength and ductility were acquired for 12p-ECAP alloy with ultimate tensile strength of 372 MPa and fracture elongation of 8%. The enhanced strength of the alloy could be ascribed to fine DRX grains, ultra-fine Ca-containing particles and dynamically precipitated nano-precipitates, while the improved ductility was mainly due to the refined and homogeneous microstructure, and weak texture with high average Schmid factors. Keywords: Mg-Al-Ca-Mn alloy, Equal channel angular pressing, Dynamic recrystallization, Precipitates, Mechanical property