Low Reduction Ratio Research Articles

Highly efficient oil-in-water emulsion separation based on innovative stannic oxide/polyvinylchloride (SnO2/PVC) microfiltration membranes

Global awareness has been raised to tackle the impact of produced water effluents from the oil and gas industries on the environment. In this work, innovative stannic oxide/polyvinylchloride (SnO2/PVC) microfiltration membranes were fabricated via the phase inversion method and their properties and performance were studied. Six membranes consisting of a fixed PVC concentration of 15 wt%, and varying loading of SnO2 nanoparticles (SnO2NPs) of 0.1, 0.25, 0.5, 1, and 1.5 wt% were cast. The results showed that embedding SnO2NPs outstandingly increased the pure water flux from 40.03 L/m2.h for the pristine PVC membrane to 104.06 L/m2.h for the 1 wt% SnO2NPs/PVC membrane when the oil in water feed concentration was 100 mg/L. This was attributed to enhancing the comprehensive porosity and hydrophilicity of the membranes as well as improving their grifted negative charge. Additionally, the maximum rejection of oil as COD and NTU removal percent achieved by the 1 wt% SnO2NPs/PVC membrane were around 99.6 % and 99.3 % respectively, compared to 83.29 % and 86.11 % using the pristine PVC membrane. Finally, the surface roughness decreased from 18.45 to 8.59 nm with adding SnO2NPs which positively improved the fouling resistance of the membranes as confirmed by obtaining low relative flux reduction and high flux recovery ratio.

Effect of cross-sectional reduction ratio on microstructure evolution of semi-solid 7075 aluminum alloy prepared by RFSIMA process

Semi-solid billets of 7075 aluminum alloy were fabricated by radial forging strain induced melting activation (RFSIMA) process. Effect of the cross-sectional reduction ratio on microstructure of fabricated 7075 aluminum alloys was analyzed. The results indicate that the average grain size of α-Al decreased from 109μm to 70μm as the cross-sectional reduction ratio increased from 0% to 73% during the 20-minute isothermal treatment at 620°C.The spheroidization trend of the grains became more pronounced; During the semi-solid isothermal treatment, the segregation of Cu at grain boundaries increased slowly with the increase in the cross-sectional reduction ratio. Zn and Mg exhibited uniform distribution without significant segregation at low cross-sectional reduction ratios (43% and below). When the cross-sectional reduction ratio reached 62%, slight segregation of Zn and Mg was observed at the grain boundaries. At a cross-sectional reduction ratio of 73%, the segregation of Zn and Mg at the grain boundaries reached a level similar to that of Cu. The optimal cross-sectional reduction ratio for the RFSIMA process was found to be 62%; the microstructural evolution mechanism of the semi-solid 7075 aluminum alloy prepared by the RFSIMA process was investigated.

Development of Manufacturing Process for High-Chromium Steel Large Welding Roll

Due to the operating conditions of weld and calibrating rolls used in the production processes of large electric-welded pipes, their material is subject to stringent wear and abrasion resistance requirements at high temperatures. The limited capabilities of conventional Cr-Mn-Ni tool steels and open die forging technologies with heat treatment processes do not provide the required performance properties for large welded rolls. Therefore, the material of the product was replaced with Cr12MoV high-chromium steel. This required identifying the formation patterns of the fine grain structure of high-chromium steel in order to adjust the production technology with adaptation to the unique conditions and equipment (12.5 MN hydraulic forging press, heating and thermal furnaces) of the forging shop. The technology was offered, which included the development of modes from heating to heat treatment with intermediate two-stage forging from Cr12MoV steel ingots in two sets of combined dies. At the first stage, deformation with a low reduction ratio ε = 5% and a relative feed rate of 0.4 per pass was provided to break and refine the carbide mesh, and at the second stage, intense deformation with a reduction ratio ε = 15% was performed. Further practical application has shown that the durability of weld rolls made from the new material increases by 20–30%.

A backdrivable 6-dof parallel robot for sensorless dynamically interactive tasks

In order to combine low mechanical impedance and sufficient interaction forces, a six-degree-of-freedom robot featuring a mechanically backdrivable transmission with a low reduction ratio is proposed in this paper. Also, a parallel architecture is used in order to allow the use of relatively large and high-torque actuators. The architecture of the robot is first presented. Then, the geometry of the robot and the ratio of the transmissions are analysed in order to ensure that the selected design parameters yield the desired properties. Shock absorbers are also included in the legs of the robot so that impacts can be applied, e.g., for the assembly of some components. Then, algorithms are presented for Cartesian stiffness control and gravity compensation of the robot. Finally, a prototype is presented and validated experimentally for position control, impedance control and impact generation. The parallel robot presented in this paper is of particular interest for industrial assembly tasks.

The Effect of Cellulose Crystalline Structure Modification on Glucose Production from Chemical-Composition-Controlled Biomass

The crystalline structure is a biomass recalcitrance factor that hinders chemical or biological access to degrade the plant cell-wall structure. However, controversy persists over whether a ratio of the crystalline region, the crystallinity index, is a critical biomass recalcitrance factor. In this study, an alkaline treatment modified from mercerization was adopted to alleviate the crystalline structure in the xylem of eucalyptus, along with hemicellulose and lignin removal via autohydrolysis and acid–chlorite treatment, respectively. Then, the glucose yield of the treated solid residues was used as a parameter of biomass recalcitrance. The alkaline treatment successfully reduced the crystallinity index, and the maximal reduction ratio was 84.9% when using an 8% sodium hydroxide solution. However, the reduction ratio of the crystallinity index was dependent on the remaining lignin content in the treated solid residues. Additionally, the lignin removal ratio showed critical influence to improve the glucose yield that was even observed in the treated solid residue having a low reduction ratio of the crystallinity index. Consequently, the cellulose crystalline structure is minimally involved with biomass recalcitrance, especially cellulase activity, at least in eucalyptus.

Laser surface melting and consecutive point-mode forging of DH36 marine steel: Dynamic recrystallization and anisotropism

DH36 marine steel was surface modified by laser surface melting process and further consecutive point-mode forging (LSM-CPF) process. The tensile properties of the coating after LSM-CPF process were significantly improved showing highest yield strength (σ0.2) and tensile strength (σb) for the sample treated with 4000 W laser power and 10% reduction ratio of 721.3 and 884.2 MPa, higher by 49.55% and 41.54% than that of the DH36 matrix, respectively. At the same time, the LSM-CPF process also results in slight anisotropism according to the tensile tests. The electron backscatter diffraction (EBSD) technique was used to investigate the dynamic recrystallization (DRX) mechanism during the CPF process. The appearance of mixed discontinuous-DRX (dDRX) and continuous-DRX (cDRX) behavior is observed under a low reduction ratio. As the deformation proceeds, the DRX mechanism is mainly of the cDRX. The anisotropism of different samples was partially as the result of the DRX behavior resulting in local non-uniformity strain gradient distribution. Additionally, the transmission electron microscope (TEM) method was employed, in order to verify the DRX mechanism. Moreover, the lamellar pearlite structures shown in the CPF zone caused the difference of deformation resistance along with the RD and TD for the 4000 W treatment samples.

Evaluation of reduction efficiencies of pepper mild mottle virus and human enteric viruses in full-scale drinking water treatment plants employing coagulation-sedimentation–rapid sand filtration or coagulation–microfiltration

Here, we evaluated the reduction efficiencies of indigenous pepper mild mottle virus (PMMoV, a potential surrogate for human enteric viruses to assess virus removal by coagulation-sedimentation–rapid sand filtration [CS–RSF] and coagulation–microfiltration [C–MF]) and representative human enteric viruses in four full-scale drinking water treatment plants that use CS–RSF (Plants A and B) or C–MF (Plants C and D). First, we developed a virus concentration method by using an electropositive filter and a tangential-flow ultrafiltration membrane to effectively concentrate and recover PMMoV from large volumes of water: the recovery rates of PMMoV were 100% when 100-L samples of PMMoV-spiked dechlorinated tap water were concentrated to 20 mL; even when spiked water volume was 2000 L, recovery rates of >30% were maintained. The concentrations of indigenous PMMoV in raw and treated water samples determined by using this method were always above the quantification limit of the real-time polymerase chain reaction assay. We therefore were able to determine its reduction ratios: 0.9–2.7-log10 in full-scale CS–RSF and 0.7–2.9-log10 in full-scale C–MF. The PMMoV reduction ratios in C–MF at Plant C (1.0 ± 0.3-log10) were lower than those in CS–RSF at Plants A (1.7 ± 0.5-log10) and B (1.4 ± 0.7-log10), despite the higher ability of MF for particle separation in comparison with RSF owing to the small pore size in MF. Lab-scale virus-spiking C–MF experiments that mimicked full-scale C–MF revealed that a low dosage of coagulant (polyaluminum chloride [PACl]) applied in C–MF, which is determined mainly from the viewpoint of preventing membrane fouling, probably led to the low reduction ratios of PMMoV in C–MF. This implies that high virus reduction ratios (>4-log10) achieved in previous lab-scale virus-spiking C–MF studies are not necessarily achieved in full-scale C–MF. The PMMoV reduction ratios in C–MF at Plant D (2.2 ± 0.6-log10) were higher than those at Plant C, despite similar coagulant dosages. In lab-scale C–MF, the PMMoV reduction ratios increased from 1-log10 (with PACl [basicity 1.5], as at Plant C) to 2–4-log10 (with high-basicity PACl [basicity 2.1], as at Plant D), suggesting that the use of high-basicity PACl probably resulted in higher reduction ratios of PMMoV at Plant D than at Plant C. Finally, we compared the reduction ratios of indigenous PMMoV and representative human enteric viruses in full-scale CS–RSF and C–MF. At Plant D, the concentrations of human norovirus genogroup II (HuNoV GII) in raw water were sometimes above the quantification limit; however, whether its reduction ratios in C–MF were higher than those of PMMoV could not be judged since reduction ratios were >1.4-log10 for HuNoV GII and 2.3–2.9-log10 for PMMoV. At Plant B, the concentrations of enteroviruses (EVs) and HuNoV GII in raw water were above the quantification limit on one occasion, and the reduction ratios of EVs (>1.2-log10) and HuNoV GII (>1.5-log10) in CS–RSF were higher than that of PMMoV (0.9-log10). This finding supports the usefulness of PMMoV as a potential surrogate for human enteric viruses to assess virus removal by CS–RSF.

Macular density alterations in myopic choroidal neovascularization and the effect of anti-VEGF on it.

To analyse macular microvascular alterations in myopic choroidal neovascularization (mCNV) and the efficiency of anti-vascular endothelial growth factor (anti-VEGF) therapy for mCNV by optical coherence tomography angiography (OCTA). A total of 123 patients were included in this retrospective study, divided into mCNV group, high myopia (HM) group, and normal group at the Affiliated Eye Hospital of Wenzhou Medical University from January 2017 to January 2019. Superficial vessel density, deep capillary density, foveal avascular zone (FAZ) area, A-circularity index (AI) and vessel density around the 300 µm width of the FAZ region density (FD) and the area of choroidal neovascularization (CNV) lesion (only for mCNV group) were measured on 3×3 mm2 OCTA images. FAZ area was corrected for axial length. Central macular thickness (CMT) was measured on OCT in mCNV group. Compared the parameters on OCTA of 3 groups and pre-anti-VEGF and post-anti-VEGF at 1, 2, 3, and 6mo follow-up in mCNV group. There were significant differences among 3 groups in superficial vessel density, deep capillary density and FD (P<0.05). FAZ area in HM group was smaller than normal group (P<0.05), but there was no significant difference between mCNV group and the other two group. AI increased in mCNV group (P<0.05). The mean CMT, area and flow area of CNV lesion decreased after treatment (P<0.05), while vessel density and FAZ didn't change. The mean CMT, area and flow area of CNV lesion statistically decreased after anti-VEGF treatment in mCNV group (P<0.05), while superficial vessel density, deep capillary density and FAZ area, AI and FD didn't change. The mean reduction ratio of lesions was 50.32% (7.07% to 100%). Lesion regression 100% was observed in 2 cases (4.88%). There was a negative correlation between the CNV lesion area and reduction ratio (r=-0.380, P=0.042) and the flow lesion area and reduction ratio (r=-0.402, P=0.030). Macular vessel density decreases, FAZ turns smaller and more irregular in mCNV eyes. Anti-VEGF therapy is efficient for mCNV without affecting vessel density and FAZ, but it is unable to completely eliminate CNV lesions in most cases. The bigger mCNV lesions have lower reduction ratio.

Analysis of Precipitation of NbC in Low Reduction Ratio Conditions

Analysis of Precipitation of NbC in Low Reduction Ratio Conditions

Construction data mining methods in the prediction of death in hemodialysis patients using support vector machine, neural network, logistic regression and decision tree.

SummaryObjectivesChronic kidney disease (CKD) is one of the main causes of morbidity and mortality worldwide. Detecting survival modifiable factors could help in prioritizing the clinical care and offers a treatment decision-making for hemodialysis patients. The aim of this study was to develop the best predictive model to explain the predictors of death in Hemodialysis patients by data mining techniques.MethodsIn this study, we used a dataset included records of 857 dialysis patients. Thirty-one potential risk factors, that might be associated with death in dialysis patients, were selected. The performances of four classifiers of support vector machine, neural network, logistic regression and decision tree were compared in terms of sensitivity, specificity, total accuracy, positive likelihood ratio and negative likelihood ratio.ResultsThe average total accuracy of all methods was over 61%; the greatest total accuracy belonged to logistic regression (0.71). Also, logistic regression produced the greatest specificity (0.72), sensitivity (0.69), positive likelihood ratio (2.48) and the lowest negative likelihood ratio (0.43).ConclusionsLogistic regression had the best performance in comparison to other methods for predicting death among hemodialysis patients. According to this model female gender, increasing age at diagnosis, addiction, low Iron level, C-reactive protein positive and low urea reduction ratio (URR) were the main predictors of death in these patients.

GenExp: Multi-objective pruning for deep neural network based on genetic algorithm

Unstructured deep neural network (DNN) pruning have been widely studied. However, previous schemes only focused upon compressing the model’s memory footprint, which had led to relatively low reduction ratio in computational workload. This study demonstrates that the main reason behind is the inconsistent distribution of memory footprint and workload of the DNN model among different layers. Based on this observation, we propose to map the network pruning flow as a multi-objective optimization problem and design an improved genetic algorithm, which can efficiently explore the whole pruning structure space with both pruning goals equally constrained, to find the suitable solution that strikes a judicious balance between the DNN’s model size and workload. Experiments show that the proposed scheme can achieve up to 34% further reduction on the model’s computational workload compared to the state-of-the-art pruning scheme [11,33] for ResNet50 on the ILSVRC-2012 dataset. We have also deployed the pruned ResNet50 models on a dedicated DNN accelerator, and the measured data have shown a considerable 6× reduction in inference time compared to FPGA accelerator implementing dense CNN model quantized in INT8 format, and a 2.27× improvement in power efficiency over 2080Ti GPU-based implementations, respectively.

Co-firing raw and torrefied rice husk with a high-Na/Ca/Cl coal: Impacts on fine particulates emission and elemental partitioning

While co-firing Si-rich biomass showed the potential for mitigating ash-related issues in low-rank coal combustion, the underlying mechanisms need further investigation. This work aims to examine the impacts of co-firing rice husk and its torrefied product with a high-Na/Ca/Cl low-rank coal on PM10 (particle size below 10 μm) emission and elemental partitioning. Combustion tests were performed on a drop tube furnace (DTF) at 1300 °C. The bulk ashes and PM10 were collected by fiberglass filters and Dekati low pressure impactor respectively. The ash samples were carefully characterized by X-ray diffraction (XRD), scanning electron microscope equipped with energy dispersive spectrometer (SEM-EDS), ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS). It is found that co-firing raw or torrefied rice husk reduces emissions of PM1 (particle size below 1 μm) together with the Na and Cl in it, mainly due to the capture of Na by coarse Si-rich particles from rice husk. The emissions of PM1-10 (particle size between 1 and 10 μm) are elevated after co-firing. This is because the formation of Ca-silicates is facilitated instead of K-silicates, thus weaken the agglomeration between the coarse particulates with melting surface from rice husk. Compared to raw rice husk, its torrefied product leads to a lower reduction ratio regarding PM1 from co-firing. Combined the results in this and previous investigations, for raw/torrefied rice husk and Xinjiang low-rank coals, the PM1 yields from both of the individual fuels and the blends almost linearly correlated with the mole ratio of (Na + K + Cl + 2S)/(Si + Al) in the ash.

EBSD research on the interfacial microstructure of the corrugated Mg/Al laminated material

In the research, corrugated Mg/Al laminated materials were fabricated at 400 °C using the AZ31B Mg plate and the 5052 Al plate through the corrugated rolling approach, the interfacial microstructure based on EBSD technique and the mechanical properties were investigated. EBSD results showed that the interfaces were well-bonded without defects at a relatively low reduction ratio of 35%. After rolling, Mg grains and Al grains were remarkably refined, the former was due to the dynamic recrystallization process and the latter was characterized by the transition from low angle grain boundaries to high angle grain boundaries with the increase of strain. During rolling process, the corrugated roll can induce the alternate texture that varied with the interfacial peak and trough positions at Mg-side. Tensile test results displayed a high tensile strength as 278 MPa and bending test exhibited excellent bending ability. The prominent mechanical properties were mainly owing to the grain refinement of the substrates, texture alternating change of the Mg alloy and low texture strength of the Al alloy.

Effects of hot-core heavy reduction rolling during continuous casting on microstructures and mechanical properties of hot-rolled plates

Abstract A slab’s internal defects that are associated with porosities significantly influence the qualities of hot-rolled plates, especially which are rolled with low reduction ratio. Hot-core heavy reduction rolling (HHR2) is an innovative technology to eliminate the porosity defects in casting steel through a single pass rolling, after the final solidification point. In this study, a Nb–Ti-microalloyed steel grade was investigated as the research object. The effects of the HHR2 process on the microstructures and mechanical properties of the final hot-rolled pates were systematically studied to evaluate the effectiveness of the process. Accordingly, the work pieces fabricated with and without the HHR2 process were reheated to 1250 °C, following which they were subjected to hot rolling, then plates with both similar thickness of 40 mm were obtained. Subsequently, the microstructures and mechanical properties of the plates manufactured using two different processes were compared. The experimental results showed that both the microstructure homogeneity and the uniformity of mechanical properties along the thickness of the plate manufactured using the HHR2 process were obviously improved. In addition, the microstructure-inheritance mechanisms of the HHR2 process at three different process stages: continuous casting, reheating, and multi-pass hot rolling, are discussed.

Impact of TRREMS on symptoms of obstructed defecation due to rectocele: predictive factors and outcomes.

The aim of this study was to evaluate the impact of the transanal repair of rectocele and rectal mucosectomy with a single circular stapler (TRREMS) on the treatment of obstructed defecation due to rectocele and to identify the predictive factors for unsuccessful results. Consecutive patients with obstructed defecation symptoms (ODS) associated with rectocele who had the TRREMS procedure were included. Each patient was assessed by echodefecography, manometry, and colonic transit time as well as the Cleveland Clinic constipation score (CCS) before therapy and at follow-up after 6months. Reduction in the CCS score was calculated as a ratio. Factors correlated with a decrease in the CCS were analyzed in a univariate analysis. A total of 81 patients were included. Nineteen patients had postoperative complications that were not severe: 7 (8.6%) had tenesmus, 6 (7.4%) stenosis (4 treated with digital dilatation and 2 with endoscopic stricturectomy), 4 (4.9%) residual mucosal prolapse treated with rubber band ligation, 1 (1.2%) early bleeding, and 1(1.2%) thrombosis. Seventy-nine (97.5%) patients had a significant clinical response with significant reduction of the CCS constipation score from median 13 (range 17-10) to 4 (range, 8-2) (p = 0.0001); only 2 patients (2.5%) had an unsatisfactory response, complaining of straining and vaginal digitation during the evacuatory effort. Patients with anismus previously treated with biofeedback had a lower reduction ratio of the CCS score compared with patients without anismus (61.2 ± 2.8% versus 70.9% ± 1.5, p = 0.0006). There were no significant differences in the reduction of the CCS according to age, parity, type of delivery, previous hysterectomy, post-menopausal status, rectal mucosal prolapse and/or associated rectal intussusception, grade of rectocele and presence of complications. The TRREMS procedure significantly improved evacuation disorders in this study. Appropriate selection of patients is key for the success of this approach. Anismus even if previously treated with biofeedback, was the main predictive factor of unsuccessful treatment.

Analysis of mortality risk from Korean hemodialysis registry data 2017.

The End-stage Renal Disease Registry Committee of the Korean Society of Nephrology collects data on the dialysis therapy in Korea through an internet-based registry program and reports it annually. In this article, the method and clinical implications of the mortality hazard ratio analyses of various clinical parameters in the 2017 registry report have been described, with the inclusion of data on four additional parameters. The mortality risk based on clinical parameters was analyzed only for hemodialysis patients. The number of registered patients with laboratory data was 13,943 (8,446 male and 5,497 female patients), and death was reported in 3,139 patients. Analysis of the effects of various clinical parameters on mortality was performed using non-linear Cox proportional hazard model with the R statistics program. For all clinical parameters, univariate and adjusted multivariate hazard ratio analyses were performed. Analysis of the mortality hazard ratio showed that low body mass index, low hemoglobin, low serum albumin, low serum phosphorus, and low urea reduction ratio were associated with a significantly increased mortality risk, whereas paradoxically high serum creatinine levels were associated with low mortality risk.

Microstructure and Damping Capacity of ZK60 Alloy Sheets Fabricated by Twin Roll Casting and Hot Rolling Process

ZK60 magnesium alloy sheets with 0.65 mm thickness were successfully fabricated by twin roll casting (TRC) and subsequent hot rolling process. Fine equiaxed grains were obtained after T6 treatment by the short-term TRC and hot rolling process, and the grain size for different reduction ratio per pass was similar. The studied sheets exhibited high strength and elongation, and the tensile strength, yield strengths, and elongation for the 10% and 30% reduction per pass were above 400 MPa, 300 MPa, and 17.0 %, respectively. The damping capacity values at low strain decreased with increasing the reduction ration per pass and the values at high strain were similar for the different reduction ration per pass. The lower reduction ratio per pass and the heat treatment between rolling passes can improve the mobility of dislocations, which indicated that this process was beneficial for improving damping capacity. Compared with higher reduction ratio per pass, the high tensile properties and damping capacity were obtained by 10% reduction per pass hot rolling process.

Vertical Phase Separation for Highly Efficient Organic Solar Cells Incorporating Conjugated‐Polyelectrolytes

AbstractHybrid organic solar cells are made through a simple one‐pot coating process with conjugated polyelectrolytes (CPEs), poly[9,9‐bis(4′‐sulfonatobutyl)fluorenealt‐thiophene‐doped (PFT‐D). The hybrid active layer incorporated with PFT‐D shows vertical phase separation by self‐assembled properties of PFT‐D, which result from a molecular dipole between the conjugated backbone and the side chain. The hybrid active layer with PFT‐D shows that homogeneous morphology, surface potential properties, and hydrophobic surface properties favor for enhancing photovoltaic performance. These results are identified by contact angle characteristics, X‐ray photoelectron spectroscopy (XPS) profiling, and X‐ray diffraction (XRD), atomic force measurement (AFM), and electrostatic force measurement (EFM) analyses. With fullerene based hybrid active layer, the power conversion efficiency (PCE) reaches to 8.7% with the enhanced short‐circuit current density (J SC), open‐circuit voltage (V OC), and fill factor (FF). The hybrid device with PFT‐D has a higher stability with a lower reduction ratio of 5.74% compared with only bulk‐heterojunction device (with reduction rate of 30.15%) and incorporating poly(3,4‐ethylene dioxythiophene)‐poly(styrene sulfonate) (PEDOT:PSS) device (with reduction rate of 10.84%). These results are also found in nonfullerene based system (PCE of 10.8%) and other conjugated polyelectrolytes system (PCE of 8.4%). These results have the potential of significantly contributing to the upsizing and commercialization of organic solar cells.

Interface strengthening and fracture behavior of multilayer TWIP/TRIP steel

Abstract Series of multilayer TWIP/TRIP steels were hot rolled at 1000 °C with different rolling reduction ratios of 25%, 50%, 60%, 70%, 80%, 90% and 94%, and some in-situ reacted Al2O3 whiskers were identified at the clad interface based on selection oxidation. The continuous oxidized films or walls were broken and separated into fine dispersed reinforcements with increasing rolling reduction ratio, which are beneficial to strengthen the interface and toughen the multilayer steels. At low rolling reduction ratio, the thick oxidation walls inhibit the grain growth and alloy element diffusion, leading to the weakness of interface bonding and interface delamination. However, at high rolling reduction ratio, the fine dispersed Al2O3 whiskers bridge the clad interface and induce grain crossing, resulting into strong interfaces and high uniform plastic deformation capacity. Moreover, the grain crossing phenomenon and inner TWIP/TRIP coordination deformation mechanism provide a novel approach for improving fracture elongation of multilayer steels.

A novel approach for preparing Cu/Al laminated composite based on corrugated roll

In this paper, Cu/Al laminated composite was prepared by a novel approach, corrugated + flat rolling (CFR) method, with low reduction ratio of 20% per pass, and the microstructure and mechanical properties were investigated. The results indicate that the preliminary combination of the composite can be realized by the first CFR pass and the composite with complete combination was obtained after the flattening rolling process. The corrugated bonding interface was formed without intermetallic phase, and the grain refinement (especially at the interface) occurred after the CFR process. Furthermore, the Cu/Al laminated composite with corrugated bonding interface exhibits outstanding tension-shear and tensile properties.