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Leafhoppers have been identified as a serious threat to different plants. To explore the characteristics of mitogenomes and reveal the phylogenetic positions of two species in the Typhlocybinae, complete mitogenomes of Singapora shinshana and Seriana bacilla were sequenced and annotated for the first time with lengths of 15,402 bp and 15,383 bp, respectively. The two mitogenomes contained 13 PCGs, 22 tRNA genes and 2 rRNA genes. The genome content, gene order, nucleotide composition, codon usage and amino acid composition are similar to those of other typical mitogenomes of Typhlocybinae. All 13 PCGs started with ATN codons, except for atp8 (TTA) and nad5 (TTG). All tRNAs were folded into a typical cloverleaf secondary structure, except for tRNA-Ser1 and tRNA-Val. Moreover, phylogenetic trees were constructed and analyzed based on all the PCGs from 42 mitogenomes using maximum likelihood (ML) and Bayesian inference (BI) methods. The results supported that eleven subfamilies are all monophyletic groups, S. shinshana and S. bacilla are members of Erythroneurini, but S. shinshana and the genus Empoascanara have a very close relationship with ((((Empoascanara sipra+ Empoascanara wengangensis) + Empoascanara dwalata) + Empoascanara gracilis) + S. shinshana), and S. bacilla is closely related to the genus Mitjaevia ((Mitjaevia dworakowskae + Mitjaevia shibingensis) + S. bacilla). These results provide valuable information for future study of evolutionary relationships in Typhlocybinae.

The high-temperature oxidation resistance of AISI 321 stainless steel for solar thermal power generation heat exchanger highly determines its service life. Therefore, in this work, aluminizing treatment and aluminizing with subsequent laser shock peening (LSP) were employed to improve the high-temperature oxidation resistance of AISI 321 stainless steel at 620°C. The results showed that these two treatments decreased the oxidation rate as compared to the base AISI 321 steel. Concretely, the optimal oxidation resistance was observed in the aluminized steel before an oxidation testing time of 144 h due to the increased the entropy of the LSP-treated specimen. After 144 h, however, the LSP-treated sample showed the best oxidation resistance because of the formation of protective α-Al2O3. For the LSP-treated samples, the large amount of sub-grain boundaries formed on aluminized layer could act as the fast short-circuit path for the outward diffusion of Al element, facilitating the rapid nucleation of α- Al2O3. Meanwhile, the aluminized layer is able to isolate the contact between oxidation environment and matrix, thereby decreasing the oxidation rate. Further, the oxidation parabolic constant D(t) of LSP-treated steel was calculated to be minimum (6.45787×10–14), which is respectively 69.18% and 36.36% of aluminized steel and 321 steel during the whole oxidation process. Consequently, the combination of aluminizing and LSP can better improve the high-temperature oxidation resistance of 321 stainless steel.

Background Identifying risk factors for occult lateral LNM in PTMC can assist in determining the necessity of LND and other measures to reduce the risk of recurrence. This study aimed to establish a nomogram for predicting the probability of lateral lymph node metastasis (LLNM) in patients with cN0 unifocal papillary thyroid microcarcinoma (PTMC).Methods We retrospectively analyzed a total of 4872 patients with cN0 unifocal PTMC who were treated at our center from January 2013 to June 2018. Logistic regression tests were used to determine the risk factors for LLNM. A nomogram was constructed based on these risk factors.Results The rate of LLNM was 3.2%. Tumors located in the upper lobe (OR = 2.56, 95% CI 1.80–3.62; p Conclusion Tumors located in the upper lobe, greater than 7 mm in size, ETE, and CLNMs, especially three or more, were independent risk factors for LLNM in cN0 unifocal PTMC. The nomogram based on these factors had favorable predictive value and consistency, but further prospective research is needed to validate these findings.

Alloys with combined outstanding strength and excellent ductility are highly desirable for many structural applications. However, alloys subjected to deformation at very high strain rates and/or cryogenic temperatures usually suffer from very limited ductility. Here, we demonstrate that a bulk CrCoNi medium-entropy alloy presents exceptional combination of high strength and excellent ductility during deformation at high strain rates over a wide temperature range. Full tensile stress-strain curves at a high strain rate of 2000 s−1 and temperatures down to 77 K were successfully obtained using an electromagnetic Hopkinson tension bar system attached with a cooling device, revealing high true ultimate tensile strength (σUTS,T) of 1.8 GPa and true strain of ∼54% at σUTS,T. These outstanding mechanical properties were mainly attributed to profuse deformation twinning. Both high strain rate and cryogenic temperature promoted deformation twinning. Grain refinement caused by deformation twinning, dislocation slip and dynamic recrystallisation added to work hardening and the excellent tensile strain.

It is unclear whether differences in clinical presentation and/or prognosis exist between prepubertal papillary thyroid cancer (PTC) and pubertal PTC. At present, there is a lack of definition for the appropriate cutoff age to define prepubertal PTC.This study retrospectively reviewed 227 pediatric PTC patients (aged ≤18 years) who underwent initial surgery from March 2000 to December 2018. The median duration of follow-up was 85 months (range, 8-258).The age range was basically linearly related to multiple risk factors, such as T3-T4 disease, distant metastasis. Age (p = 0.032) was an independent risk factor for recurrence and persistent disease. Patients aged14 years had obviously higher rates of extensive disease. The 10-year disease-free survival (DFS) rate of patients aged14 years was 59.5% and that of patients aged ≥14 years was 82.6% (p = 0.004).Fourteen years of age may be an appropriate cutoff to differentiate prepubertal PTC from pubertal PTC.

The effects of tensile temperatures ranging from 100 K to 900 K on the phase transition of hexagonal close-packed (HCP) zirconium were investigated by molecular dynamics simulations, which were combined with experimental observation under high resolution transmission electron microscopy. The results show that externally applied loading first induced the HCP to body-centered cubic (BCC) phase transition in the Pitsch-Schrader (PS) orientation relationship (OR). Then, the face-centered cubic (FCC) structure transformed from the BCC phase in the Bain path. However, the HCP-to-BCC transition was incomplete at 100 K and 300 K, resulting in a prismatic-type OR between the FCC and original HCP phase. Additionally, at the temperature ranging from 100 K to 600 K, the inverse BCC-to-HCP transition occurred locally following other variants of the PS OR, resulting in a basal-type relation between the newly generated HCP and FCC phases. A higher tensile temperature promoted the amount of FCC phase transforming into the BCC phase when the strain exceeded 45%. Besides, the crystal stretched at lower temperatures exhibits relatively higher strength but by the compromise of plasticity. This study reveals the deformation mechanisms in HCP-Zr at different temperatures, which may provide a better understanding of the deformation mechanism of zirconium alloys under different application environments.

The mechanical properties and microstructures of a near β-Ti alloy (Ti-3.9Al-5.47Mo-4.74V-1.0Cr-1.71Fe, wt%) subjected to solution treatment and then single aging or double aging treatments were investigated by transmission electron microscopy. Single aging treatment results in an increased strength, but a decreased ductility, due to the co-precipitation of the α and ω phases or the exclusive precipitation of the α phase. Double aging breaks the strength and ductility trade-off, resulting in the highest yield strength of 1119 MPa and the largest ductility of 11%. The superior mechanical properties are ascribed to the thick α phase, FCC structure, and FCC nanotwins in the double aging treated samples.

{11 2 - 2} compression twin plays an important role in accommodating deformation along the c axis of HCP metals. However, the studies on the interface structure of {11 2 - 2} twin boundary (TB), especially the twin tip, and the corresponding local stress release mechanism are still limited. This work studied the interface characters of {11 2 - 2} TB of a deformed pure titanium by transmission electron microscope. The {11 2 - 2} TB presented serrated character, consisting of coherent twin boundary (CTB) and (0002)T // (11 2 - 2 - )M or (11 2 - 2 - )T // (0002)M steps, and the twin tip was fully composed of the basal-pyramidal (BPy) and pyramidal-basal (PyB) steps. The twin tip presents asymmetric morphology and the step height at the twin tip is much larger than that away from the twin tip. Two types of local stress accommodation mechanisms were observed: zonal dislocation emission and hexagonal close packed structure to face-centered cubic structure transformation. The zonal dislocation was produced by the dissociation of the 1/3 2 - 3 - > dislocation that was nucleated at the twin tip and the phase transformation was introduced by emission of Shockley partial dislocations from the {11 2 - 2} twin boundary.

Background Madelung disease (MD) is a rare disorder of fat metabolism, resulting in diffuse, symmetrical and painless deposition of adipose tissue in subcutaneous superficial fascial space and/or deep fascia space of the head, neck and shoulders, etc. Case summary We report a case of MD accompanied by type 2 diabetes in a 61-year-old Chinese male. The patient presented with progressive fat deposition over the mandible, neck, abdomen and elbows. He had a history of smoking and alcohol abuse. Excessive fat deposition was seen in the mandible, elbows and the abdominal area of the patient by ultrasonic examination. Computed tomography showed diffuse and marked soft masses (fat density) in the subcutaneous superficial fascia space of the neck. The patient was diagnosed with MD. He was advised to abstain from alcohol and was followed up regularly. Conclusion This report discusses the pathogenesis, diagnosis and treatment of MD, and raises the clinician's awareness of this disease.

Jian Wang, Yiming Zhu, Song Ni, Shaoyan Liu Department of Head and Neck Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, People’s Republic of ChinaCorrespondence: Shaoyan LiuDepartment of Head and Neck Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, People’s Republic of ChinaTel +86-10-87787190Email lsaoyan_liu@163.comPurpose: Long noncoding RNAs growth arrest-specific 5 (GAS5) exerts important functions in modulating various tumor behaviors. However, the role of lncRNA GAS5 in laryngeal squamous cell carcinoma (LSCC) remains unknown.Materials and Methods: Cell viability and apoptosis were, respectively, detected by cell counting kit-8 and flow cytometry, DIANA-LncBase V, Starbase, TargetScan and a dual-luciferase reporter gene assay were employed to assess the relationship among GAS5, miR-26a-5p and uncoordinated 51-like kinase 1 (ULK2), and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot were performed to detect the expression of autophagy-relative factors.Results: The expression level of GAS5 was frequently decreased in LSCC cell lines, and up-regulated GAS5 inhibited AMC-HN-8 cells viability and induced apoptosis. More importantly, we found that GAS5 activated autophagy, with enhanced autophagy-related proteins after GAS5 overexpression. While down-regulated GAS5 had opposite results in Tu 177 cells, GAS5 was found to act as a microRNA sponge in a pathway to regulate miR-26a-5p and its target gene ULK2. MiR-26a-5p mimics inhibited apoptosis and autophagy, which were reversed by GAS5 and siGAS5 in AMC-HN-8 cells and Tu 177 cells, as well as ULK2 in AMC-HN-8 cells. Meanwhile, the concomitant downregulation of ULK2 and miRNA-26a-5p inhibitor decreased the miRNA-26a-5p inhibitor-induced apoptosis and autophagy.Conclusion: This is the first report of LncRNA GAS5 acting as a tumor suppressor in LSCC by regulating the miR-26a-5p/ULK2 axis, and it could be a new target for gene therapy in LSCC.Keywords: long noncoding RNAs growth arrest-specific 5, laryngeal squamous cell carcinoma, miR-26a-5p, apoptosis, autophagy

The effect of elemental segregation on local hardness and microstructural evolution introduced by high strain-rate deformation in a CrMnFeCoNi high entropy alloy was investigated. Mn and Ni elemental segregation to interdendritic boundaries occurs during the solidification process and is intensified by dynamic deformation. Local hardness is reduced in the Mn and Ni enriched areas, which may be due to the increase of local stacking fault energy that changes the deformation mechanisms. This leads to the alternation of soft and hard regions and the structure is effective in hindering the propagation of adiabatic shear bands that would toughen the material.

The plate-shaped θ′ (Al2Cu) precipitate acts as one of the primary strengthening phases in Al-Cu alloys. The interface, especially the semicoherent interface, between Al-Cu solid solution (αAl) and θ′ phase contains a lot of clues about phase transformations. Thus, these interfacial structures in an Al-Cu alloy after high-temperature and longtime aging have been analyzed in detail using atomic-scale high-angle annular dark-field scanning transmission electron microscopy and first-principles calculations in this work. It was found that the lateral growth of θ' precipitates is subjected to a combination of several major mechanisms under this aging condition. Except for some common intermediate phases, two novel and striking structures were observed on the interface, which implies two alternative atomic diffusion mechanisms for θ′ precipitate growth. For one condition, the atomic diffusion from αAl to θ′ phase transformation adopts an interstitialcy mechanism based on additional Al atoms. For the other condition, the diffusion is carried out through Al atoms. Both mechanisms are distinctly different from the previous theory based on direct diffusion of Cu atoms. The first-principle calculations also confirm that these newfound diffusion processes are energetically favored.

In this paper, we observe for the first time that a metastable beta-Zr in the body-centered cubic (BCC) structure can form via a new phase transformation route. The as-received alpha-Zr in the hexagonal closed-packed (HCP) structure transforms partially to the gamma-Zr in the face-centered cubic (FCC) structure via Shockley partial dislocations during deformation, while the gamma-Zr can continuously transform to the beta-Zr by a uniform shear along the $$\left\langle {112} \right\rangle_{{{\text{FCC}}}}$$ direction on the $$\left\{ {111} \right\}_{{{\text{FCC}}}}$$ plane during subsequent hot deformation. The beta phase is in a Pitsch–Schrader relationship $$((110)_{BCC}||(0001)_{HCP}, [1\overline{1}0]_{BCC}||[10\overline{1}0]_{HCP})$$ with the matrix alpha phase and in a Nishiyama–Wassermann relationship $$((110)_{{{\text{BCC}}}} ||(1\overline{1}\overline{1})_{{{\text{FCC}}}} , [1\overline{1}0]_{{{\text{BCC}}}} ||[12\overline{1}]_{{{\text{FCC}}}} )$$ , with the gamma phase, both of which have not been reported in Zr previously. Combined with corresponding molecular dynamics simulations, the phase transition mechanism and stability of the beta phase are studied. The results show that the beta-Zr phase can be retained in the gamma phase when the cooling is fast enough.

The CoCrNiMox (x = 0, 0.1, and 0.2 in molar ratio) medium entropy alloys (MEAs) were fabricated by vacuum arc melting, followed by cold rolling and annealing treatments. The X-ray diffraction (XRD), electron back-scattered diffraction (EBSD), and transmission electron microscopy (TEM) were employed to characterize the microstructures. It has been shown that the CoCrNi MEA has a single FCC phase and the Mo-containing MEAs contain (Cr, Mo)-rich σ precipitates. In addition, the Mo addition caused significant grain refinement, due to the fact that the presence of σ phase exerts a strong pinning effect on the grain boundary migration. The hardness testing results indicate an increment in Vickers hardness from 187.5 ± 4.5 Hv of CoCrNi alloy to 309.5 ± 10.3 Hv of CoCrNiMo0.2 alloy. The yield strength and ultimate tensile strength also increase from 339 ± 2 to 644 ± 5 MPa and from 810 ± 5 to 1071 ± 17 MPa, respectively, but the elongation drops from 88.4 ± 4.0% to 29.5 ± 7.6%. The grain refinement and the precipitation of σ phase make synergistic contribution to the reinforcement of Mo-containing CoCrNi-based MEAs. The details and explanations in this study may guide the future design and research of the CoCrNi-based quaternary alloys with enhanced properties.

The phase transformation, deformation mechanism and their correlation in a cold-rolled Ti-5at.%Al alloy were investigated. Two types of phase transformations from a hexagonal close-packed (HCP) structure to a face-centered cubic (FCC) structure were observed: the basal-type (B-type) with an orientation relationship of 2 - 10> HCP // 1 - 0> FCC and {0001}HCP//{111}FCC, and the prismatic-type (P-type) with an orientation relationship of 2 - 10> HCP // 1 - 0> FCC and {10 1 - 0} HCP //{110} FCC . The two types of transformations both accommodate the strain along the axis of the HCP matrix. With the proceeding of deformation, different deformation mechanisms were activated in the FCC and the HCP structures, respectively, which led to a faster grain refinement rate in the FCC structure than in the HCP matrix. Deformation twins with zero macroscopic strain were prevalent in the FCC domains produced by the B-type transformation, while deformation twins with macroscopic strain were normally observed in the FCC domains produced by the P-type transformation. This is in accordance with the lattice mismatches produced during phase transformation. The easy occurrence of deformation twinning in the FCC structure contributed significantly to the grain refinement process. In addition, the interaction between neighboring FCC domains produced by the two types of phase transformations also accelerated the grain refinement process.

Aluminum (Al) matrix composites gain tremendous attention as candidates for lightweight structural materials. Interfaces between the matrix and reinforcements, long-standing concerns, are critical in determining the mechanical properties of Al matrix composites. Unlike the conventional thoughts that focus on raising the interfacial wettability, a novel interfacial nano-decoration strategy is reported to enhance the interfacial adhesion by forming a diffusion interface between Al and carbon nanotubes (CNTs) through copper (Cu) coating on the surface of CNTs. The resulted Cu-rich nanolayers through this strategy compromise the large interfacial misfit strain between Al and CNTs. Such unique interfacial structure improves the strengthening efficiency of CNTs and benefits the plastic deformation of the Al matrix, and thus contributes to a simultaneous increase in strength and ductility and breaks the ubiquitous strength-ductility trade-off dilemma in the structural material design. Consequently, we achieve an exceptional combination of tensile strength (391 MPa) and tensile elongation (15.7%) for our composite that surpasses its counterparts. The present tactic thus paves a new way to process high-performance Al matrix composites.

The effects of temperature and Ti content on the deformation mechanisms of pure Zr and Zr-Ti alloys were investigated by transmission electron microscopy. The results indicate the existence of a relation between deformation-induced phase transformation from a hexagonal close-packed structure to a face-centered cubic structure and { 10 1 ¯ 1 } deformation twinning. That is, when one is suppressed, the other will be promoted. The phase transformation was suppressed while the { 10 1 ¯ 1 } compressive twinning was promoted with increasing the rolling temperature and/or Ti content. This can be attributed to the activation of basal dislocations at high temperature and the increased stacking fault energy with Ti content.

The absence of lymphatic vessels in tumors leads to the retention of interstitial fluid, and the formation of an inverse pressure difference between the tumor and blood vessels hinders drug delivery deep into the tumor, which leads to tumor recurrence and metastasis. Therefore, we designed a novel strategy to downregulate tumor interstitial fluid pressure (TIFP) by water splitting in the tumor interstitium based on piezoelectric catalysis nanomedicine. First, the chemotherapeutic drug doxorubicin (DOX) was loaded on the piezoelectric catalytic material MoS

BackgroundMedullary thyroid cancer (MTC) can only be cured by surgery, but the management of lateral lymph nodes is controversial, especially for patients with cN0+cN1a. To address this challenge, we developed a multivariate logistic regression model to predict lateral lymph node metastases (LNM).MethodsWe retrospectively collected clinical data from 124 consecutive MTC patients who underwent initial surgery at our institution. The data of 82 patients (from 2010 to 2018) and 42 patients (from January 2019 to November 2019) were used as the training set for building the model and as the test set for validating the model, respectively.ResultsIn the training group, the multivariate analyses indicated that male and MTC patients with higher preoperative basal calcitonin levels were more likely to have lateral LNM (P = 0.007 and 0.005, respectively). Multifocal lesions and suspected lateral LNM in preoperative ultrasound (US) were independent risk factors (P = 0.032 and 0.002, respectively). The identified risk factors were incorporated into a multivariate logistic regression model to generate the nomogram, which showed good discrimination (C-index = 0.963, 95% confidence interval [CI]: 0.9286–0.9972). Our model was validated with an excellent result in the test set and even superior to the training set (C-index = 0.964, 95% CI: 0.9121–1.000).ConclusionHigher preoperative basal calcitonin level, male sex, multifocal lesions, and lateral lymph node involvement suspicion on US are risk factors for lateral LNM. Our model and nomogram will objectively and accurately predict lateral LNM in patients with MTC.

Pneumatic lift train together is the concept of under the background of further accelerate the speed of high-speed train running speed, in order to under higher speed train the whole life cycle cost, the researchers put forward the concept of aerodynamic lift high-speed train together, break through the traditional high-speed train aerodynamic shape design concept, combined with high speed trains and aircraft their respective advantages, hope that through increasing train aerodynamic lift, It is hoped that by increasing the aerodynamic lift of the train, the overall energy saving and consumption reduction of the high-speed train can be achieved. In this paper, a high lift airfoil is optimized to improve the lift coefficient as much as possible while the drag coefficient is basically unchanged. The thickness and drag coefficient of the optimized airfoil are almost unchanged at the designed Angle of attack, and the lift coefficient is increased by 13%. A flat wing is designed based on the optimized airfoil, and the influence of wall effect and tandem wing layout on the lift drag coefficient of the wing is studied. A better aerodynamic lift cooperative train tandem wing layout is obtained, which can reduce the weight of a single train by 17%.

Interior tomography is a promising technique that can be used to image large objects with high acquisition efficiency. However, it suffers from truncation artifacts and attenuation value bias due to the contribution from the parts of the object outside the ROI, which compromises its ability of quantitative evaluation in material or biological studies. In this paper, we present a hybrid source translation scanning mode for interior tomography, called hySTCT—where the projections inside the ROI and outside the ROI are finely sampled and coarsely sampled respectively to mitigate truncation artifacts and value bias within the ROI. Inspired by our previous work—virtual projection-based filtered backprojection (V-FBP) algorithm, we develop two reconstruction methods—interpolation V-FBP (iV-FBP) and two-step V-FBP (tV-FBP)—based on the linearity property of the inverse Radon transform for hySTCT reconstruction. The experiments demonstrate that the proposed strategy can effectively suppress truncated artifacts and improve the reconstruction accuracy within the ROI.

Single tumor starvation therapy can activate other signaling pathways in tumor cells and easily induce tumor cell metastasis. This research proposes an intelligent nanoparticle, which is effectively combined with plasmonic and immunotherapy to realize a new strategy of "upstream consumption and downstream blocking" of nutrients in tumor sites. The intelligent nanoparticle (Ag-G/C@M) was composed of Ag NCs loaded with glucose oxidase (GOx), catalase (CAT) and coated with the tumor cytomembrane (M). Homologous targeting of tumor cytomembrane facilitated more delivery of Ag-G/C@M to tumor sites and then the plasmonic excited from Ag-G/C@M can increase the catalytic efficiency of the enzymatic reaction. Hydrogen peroxide (H2O2) produced by Ag-G/C@M through the consumption of glucose is further catalyzed by CAT to produce oxygen (O2). This self-reinforcing cascade reaction not only consumes the nutrients of tumor cells, but also the plasmonic-induced photothermal therapy can further stimulate the immune system to produce interferon-γ (IFN-γ), blocking angiogenesis and restricting the nutrient supply of tumor cells. This strategy takes the nutrition necessary for cell survival as the entry point, through endogenous continuous consumption of intracellular nutrients and containment of exogenous supplementation, combined with plasmonic thermal effect and immunotherapy to kill tumor cells, which provides a new way of treating cancer safely and effectively.

Designing high entropy alloys (HEAs) with high strength and excellent ductility has attracted extensive scientific interest. In the present work, the CALPHAD (calculation of phase diagrams) method was applied to guide the design of an (FeCoNi)92Al2.5Ti5.5 HEA strengthened by precipitation hardening. The grain size as well as the size and volume fraction of the precipitates was tailored via a thermo- mechanical process to optimize the mechanical properties. The uniformly dispersed nano-precipitates are Ni3(Al,Ti)-type precipitates with an L 12 ordered structure presenting a fully coherent interface with the face-centered cubic (FCC) matrix. The yield strength of the alloy increases from 338.3 to 1355.9 MPa and the ultimate tensile strength increases from 759.3 to 1488.1 MPa, while the elongation maintains a reasonable value of 8.1%. The striking enhancement of strength is mainly caused by the precipitate’s hardening mechanism, which is evaluated quantitatively by various analytical models. The deformation-induced microbands and the coherent precipitates sheared by dislocations are the deformation and strengthening mechanisms contributing to the superior combination of ductility and strength in the present HEA. This investigation demonstrates that the CALPHAD method is beneficial to the design and optimization of HEAs.

In this work, mechanical properties and phase transformation of a near-beta Ti-5Al-5Mo-5V-1Cr-1Fe alloy subjected to hot rolling deformation were investigated. Detailed transmission electron microscopy characterizations indicated that beta to alpha phase transformation occurred during hot rolling process, accompanied by the variant selection of the alpha precipitates. In addition, the hexagonal close-packed structure to face-centered cubic structure transformation was also observed inside the alpha phase near the alpha/beta interface. The relationship between the phase transformations and the mechanical properties of the alloy was systematically discussed. This work provides a new strategy to design strong and ductile Ti alloys.

Precipitation hardening is an effective way to strengthen Mg alloys as precipitates can reduce the mobility of dislocations. Previous investigations suggest that pyramidal ⟨c + a⟩ dislocations can only bypass precipitates. Here we provide solid atomic resolution evidence that ⟨c + a⟩ dislocations can shear through plate precipitates, leaving behind shear trace lines. The possible shearing process was analyzed based on the crystallographic orientation relationship between the precipitates and the Mg matrix.

An equiatomic FeCrCoMnNi high-entropy alloy was processed by cold rolling and then isochronous annealing treatments. The dependence of the tensile properties and microstructure of the alloy on the annealing temperature was investigated. Long-range ordered structure, Cr-rich precipitates, heterogeneous structure with different recrystallization degrees, and homogeneous structure with different grain sizes can be obtained via regulating the annealing temperature. It is operable to obtain optimal microstructure of the alloy and thus beneficial to the mechanical properties by varying the annealing temperature. This work provides a new concept to fabricating FeCrCoMnNi alloy with a combination of high strength and large ductility.

The microstructural evolution and mechanical properties of a Zr70Ti30 alloy subjected to cold rolling were investigated. The microstructural evolution against thickness reduction can be summarized as: equiaxed coarse grains → dislocation generation and multiplication → formation of microbands → formation of twins in microbands → dislocation–twin boundary interactions. At the early stage of rolling, dislocation slip dominated the plastic behavior until the thickness reduction of rolling reached 20%. Twinning gradually took place and became the major mechanism as the deformation proceeds. The occurrence of twinning would change the orientation of grains, which in turn facilitates subsequent dislocation slip. Three slip systems, including prism , basal and pyramidal , and two types of twinning { 10 1 ¯ 1 } and { 10 1 ¯ 2 } were observed during deformation. The hardness evolution indicates a strain hardening process during cold rolling.

Nitrogen doped Co-Cr-Mo-W based alloys with substantially enhanced strength and good ductility were successfully fabricated by selective laser melting (SLM). The results showed that nitrogen suppressed the formation of hexagonal close packed (hcp) e phase martensitic through hindering the Shockley partial dislocations slip. Combining with SLM, doping nitrogen into Co-Cr-Mo-W alloys provides an effective strategy to significantly improve the strength and maintain the ductility simultaneously. The yield strength, ultimate tensile strength and elongation of 0.086 (wt.%) N-doped Co-26Cr-5Mo-5W alloys are ∼1027 MPa, ∼1295 MPa and ∼18.2%, respectively.