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In this study, the extruded Mg-Zn-Mn-Ce-Ca alloy tube with a low compression anisotropy along the ED, 45ED and TD was prepared. The effect of the second phases, initial texture and deformation behavior on this low mechanical anisotropy was investigated. The results revealed that the alloy tube contains the high content (Mg1-xZnx)11Ce phase and the low content of Mg12Ce phase. These second phases are respectively incoherent and coherent with the Mg matrix, and their influence can be ignored. Additionally, the alloy tube exhibited a weak basal fiber texture, where the c-axis was aligned along the 0° ∼ 30° tilt from TD to ED. Such a texture made the initial deformation (at 1.0% ∼ 1.6% strain) of the three samples controlled by comparable basal slip. As deformation progressed (1.6∼9.0% strain), larger amounts of ETWs nucleated and gradually approached saturation in the three samples, re-orienting the c-axis to a 0°∼±30° deviation with respect to the loading directions. Meanwhile, the prismatic 〈a〉 and pyramidal slips replaced the dominant deformation progressively until fracture. Eventually, the similar deformation mechanisms determined by the weak initial texture in the three samples contribute to the comparable strain hardening rates, resulting in the low compressive anisotropy of the alloy tube.

Traditional hot-dip galvanized coatings, typically single-silver in color, present increasing aesthetic challenges in diverse applications, while prevailing organic coating methods involve complex processes with high energy consumption and pollution emissions. In this study, a novel hot-dip process for in-situ synthesis of color coating on steel was proposed, capable of producing various uniform color coating. The microstructure of color coatings on steel was systematically examined, and an assessment of their corrosion and weather resistance was conducted. The results demonstrate the sequence of typical color variation is gold, purple, blue, cyan, red, green, and grey. By controlling the immersion temperature range, and regulating the final stable color of the oxide film. The coloration mechanism mainly is attributed to the light interference on the Mn oxide film. The cyan and brown coatings mainly consist of the dense rod-like ζ-FeZn13 phases which provide a structural foundation for corrosion resistance. Furthermore, the brown coating exhibited excellent weather resistance.

In this paper, a mathematical model validated by in-situ temperature measurement data of the direct chill (DC) casting process has been established in order to study the domination and effect of multi-parameters including secondary cooling water flow rate (Q), casting speed (V), condition of primary cooling, and spraying water temperature (Tw) on DC casting index of sump depth (dsump), maximum and minimum temperature gradient (Tg,max and Tg,min) at mushy zone and shape of solidus line. Further, the height of impingement zone (Hip) is systematic quantitative analysis by a novel designed test (Hip=1.08865Q`+0.06272V−4.75597). The calculated temperature using the numerical simulation exhibits a good match with the actual temperature measurement data. The results of multi-factors on index by the designed orthogonal test indicate that V dominates the dsump (dsump=0.033+27.74V) and Tg,min (Tg,min=2569.15−766342.20V) at mushy zone, Q dominates the Tg,max (Tg,max=9195.12+2344770Q−27.83Tw) by analysing the range (R), variance (S) and significance (F). Likewise, by discussing the combination of R, S, F and microstructure observation, the priority influencing the shape of solidus line at center part was V. The Q dominates the shape of solidus line at the position between the center and edge part.

The corrosion behaviour of Nd alloyed magnesium alloy AZ80 in three simulated concrete pore solutions (SCPs) was studied using corrosion immersion tests and electrochemical tests. The study investigated the effects of the composition and pH of the SCPs on the corrosion properties of AZ80 and AZ80-1.0Nd using aluminum alloy AA6061 as a reference. The SCP1, SCP2, and SCP3 solutions were the simulated concrete pore solutions with different carbonation stages at pH 13.5, 12.5, and 9.7 respectively. The corrosion mainly in the form of localized corrosion, developed significantly along the transverse direction, and less in the vertical direction. AZ80 and AZ80-1.0Nd exhibited the best corrosion resistance in the SCP2 solution, which was attributed to the formation of a dense protective film on the surface. The corrosion in the high alkalinity SCP1 solution was first enhanced within 12 h and then somewhat decreased within 72 h attributed to the destruction and re-formation of the surface film. AA6061 corroded severely in the SCP1 solution and suffered significantly less corrosion in the SCP2 and SCP3 solutions. Nd alloying contributed to the reduced corrosion rates of AZ80 in the simulated concrete pore solutions, attributed to changes in the microstructure and electrochemical properties.

The current magnesium (Mg) alloy wheel formed by backward extrusion (BE) often has upper rim cracking and coarse microstructure at the spokes to reduce the yield, and a reasonable die structure design is an important factor to improve the yield of the wheel, therefore, this poses new challenges on the die structure of Mg alloy wheels. The paper selected four parameters for the three positions of the wheel for optimizing the die structure by analyzing the forming characteristics and defects of Mg alloy wheels. Based on the actual extrusion conditions of the Mg alloy wheel, a numerical model of Mg alloy wheels formed by BE was established, and the effect of a single parameter on the physical field of the forming process was analyzed by numerical simulation in turn, and then the four parameters of the die structure were progressively combined and optimized to determine the better three positions of the Mg alloy wheel die, while an experimental trial was conducted to verify the accuracy of the results of this study. The results show that increasing the spoke thickness, decreasing the spoke inclination angle, increasing the punch fillet radius and increasing the inner fillet radius of the upper rim can effectively improve the metal flow and make the billet filling more smoothly. The optimized die structure can make the temperature at the wheel bottom lower and evenly distributed, the stress concentration at the window is relieved, the filling at the upper rim is complete, and the macroscopic tearing phenomenon disappears.

In this study, the extruded Mg–Zn–Mn–Ce–Ca alloy tube with a weak basal fiber texture, i.e. the {0001} plane is distributed along the TD with 0°∼30° deflection towards ED, was fabricated. The alloy tube exhibits a low mechanical anisotropy in the tensile process at room temperature. To clarify the relationship between the weak texture and the low mechanical anisotropy, the microstructure and deformation mechanism of the alloy tube in the tensile process along the ED, 45ED and TD were studied. The results revealed that during yielding, the deformation in ED sample was governed by predominant prismatic slip, and a portion of additional basal slip and lowest pyramidal slip, while predominant basal slip and accompanied by a high fraction of prismatic slip and lowest pyramidal slip for both 45ED and TD samples. These relatively high additional slips result from the weak texture, which attenuates the deformation differences among the three samples. After yielding, the three samples underwent similar prismatic slip transition and twin nucleation quantity. Additionally, the {0001} plane displayed to converge towards the RD after tensile fracture, which may be related to the twins and intragranular slip. Especially for 45ED and TD samples, relatively high basal slip may cause their {0001} plane to tend to be parallel to the loading direction. In summary, the similar deformation mechanisms governed by weak texture along the three directions resulted in the low mechanical anisotropic of the alloy tube.

This work investigated the acoustic pressure distribution and relevant cavitation area of the dual-frequency ultrasonic field (DUF) in magnesium melt using numerical simulation. Associated experiments were also implemented to understand the grain refinement of DUF. DUF weakens the acoustic attenuation and then enlarges the potential cavitation area than the single-frequency ultrasonic field (SUF). Such improvement promotes its grain refinement efficiency, which is 17.7% and 24% higher than 15 kHz and 20 kHz SUF, respectively. Both yield strength and ultimate tensile strength are improved by DUF melt treatment. The improvement of mechanical properties for ultrasonic melt treated alloy is attributed to the grain refinement and the texture evolution. To optimize the grain refinement of DUF melt treatment, choosing the appropriate input acoustic pressure ratio is important. Under the premise of relevant symmetrical distribution of the cavitation area, increasing the acoustic pressure input for 15 kHz ultrasonic is beneficial to improve the grain refinement efficiency.

Reducing the yield asymmetry is very important concern for wrought Mg-Li alloys. In this study, Mg-5Li-3Al-2 Zn (LAZ532) alloy was successfully produced by hot-extrusion followed by multi-pass rolling at 573 K. Microstructure evolution, mechanical properties and yield asymmetry reducing of LAZ532 alloys at different rolling passes were studied. By observing microstructure using transmission electron microscopy showed that a small amount of ultra-fine AlMg4Zn11 and nano Li3Al2 phases existed in the alloy. With the increasing of rolling passes, the grains of the alloys were obviously refined, and comprehensive mechanical properties were dramatically improved. Meanwhile, it also showed an excellent tension and compression yield symmetry (TYS/CYS was about 1). The results showed that the combined action of the weak {0001} basal lamellar texture, grain refinement and addition of Li element could effectively improve the yield symmetry. Furthermore, based on theoretical analysis, the yield strength in the alloys mainly depended on the strengthening contributions of LAGBs and HAGBs, and strengthening effect of HAGBs most (∼50%) to the yield strength improvement.

Explaining the wetting mechanism of Cu–P brazing materials and Cu remains challenging. This fundamental research aims to reveal the wettability mechanism of Si, Sn, and Zr doping on the interfacial bond strength of the Cu3P/Cu system through the first principles study. We carried out several sets of calculations to test the validity of the result; included in the work are those used to establish the interfacial structure and to analyze the effect of doping on the wettability. Specific analysis was carried out in terms of three aspects: the work of adhesion (Wad), the charge density difference, and the density of states (DOS). The calculated results show that doping with Si, Sn, and Zr elements can effectively improve the wettability within the CuP/Cu interface with very high accuracy, and is particularly effective when doped with Zr. These results provide an insightful theoretical guide for enhancing the CuP/Cu system’s wettability by adding active elements.

BackgroundMatrix metalloproteinases (MMPs), a kind of proteases, have a critical function in cancer occurrence, invasion, and migration. MMP gene variants (e.g., MMP-2, MMP-7, and MMP-9) can affect the biological functions of these enzymes and lead to the occurrence and progression of cancer, which has become a hot topic in recent years, but the corresponding results are still controversial. In this context, here, the meta-analysis was conducted for assessing the relations of variants in MMP-2, MMP-7, and MMP-9 with the risk of various cancers.MethodsPubMed, Web of Science, and Medline were systemically searched, and data were extracted from all eligible studies so as to investigate the susceptibility of MMP-2, MMP-7, and MMP-9 to different types of cancers. The association between a variant in MMP and cancer susceptibility was analyzed through odds ratios (ORs) as well as 95% CIs. The Venice criteria and false-positive report probability (FPRP) were adopted to evaluate epidemiological evidence of significant associations discovered.ResultsThe associations between the variants of MMPs and cancer risk in 36,530 cases and 41,258 controls were found, with 12 associations (MMP-2 rs243865 with esophageal cancer and lung cancer, MMP-7 rs11568818 with bladder and cervical cancer, and MMP-9 rs3918242 with breast cancer) rated as strong associations for cancer risk and 7 and 15 as moderate and weak associations, respectively. These significant associations were mostly found in Asians.ConclusionsThese findings support the relations between variants of MMP-2, MMP-7, and MMP-9 and various cancers risk, demonstrating the credibility of these relations.

Immunotherapy alone or chemo-immunotherapy has recently been recommended for treating advanced lung carcinoma in patients without driver mutations. However, the efficacy of immunotherapy and molecular mechanism in large-cell lung cancer (LCLC) remains unclear. Here, we reported a rare case of multiple fulminant postoperative body and mouth metastases in LCLC treating with combination immunotherapy. Initially, the patient was diagnosed as early stage LCLC and underwent a radical resection of the right lower lobe. Just one month later, multiple fulminant body and mouth lesions appeared in the right upper arm, right elbow, right waist, and tongue root. Meanwhile, serum neuron specific enolase (NSE) concentration dramatically increased from 12.12 to 30.14 ng/ml. Immumohistochemistry findings demonstrated moderate PD-L1 expressions with tumor proportion score (TPS), while next-generation sequencing indicated moderate tumor mutational burden (TMB) levels and gene mutations in PBRM1 L1230P and TP53 L194R of both foci. Besides, loss of heterozygosity (LOH) at human leukocyte antigen (HLA) class I (HLA-A*02:03, HLA-B*55:02 and HLA-C*12:03) were detected in the right upper arm metastasis, which may facilitate malignant postoperative metastases in this case. Notably, this patient received combination therapy with anti-PD-1 antibody sintilimab plus anlotinib, and achieved a partial response for at least 12 months. Using an integrated computational method, the mutant peptide TEIPENDIPL derived from PBRM1 L1230P was predicted to be a specific neoantigen and could still be presented by HLA-B*40:01. This case suggests that immunotherapy plus antiangiogenic drug may provide an alternative therapeutic option for advanced LCLC patients without common gene mutations.