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Recent losses in the abundance and diversity of arthropods have been documented in many regions and ecosystems. In grasslands, such insect declines are largely attributed to land use, including modern machinery and mowing regimes. However, the effects of different mowing techniques on arthropods remain poorly understood. Using 11 years of data from 111 agricultural grassland plots across Germany, we analyzed the influence of various grassland management variables on the abundance and abundance‐accounted species richness of four arthropod orders: Araneae, Coleoptera, Hemiptera, and Orthoptera. The analysis focused on detailed mowing information, for example, days after mowing and mower type, and compared their effect with other aspects of grassland management, that is, rolling, leveling, fertilization, and grazing. We found strong negative effects of mowing on all four arthropod orders, with arthropod abundance being lowest directly after mowing and steadily increasing to three to seven times the abundance after 100 days post‐mowing. Likewise, Hemiptera and Coleoptera species richness was 30% higher 100 days after mowing. Mower width showed a positive effect on Orthoptera abundance, but not on the other arthropods. Arthropod abundance and Coleoptera species richness were lowest when a mulcher was used compared to rotary or bar mowers. In addition to mowing, intensive grazing negatively affected Orthoptera abundance but not the other orders. Mowing represents a highly disturbing and iterative stressor with negative effects on arthropod abundance and diversity, likely contributed by mowing‐induced mortality and habitat alteration. While modifications of mowing techniques such as mower type or mowing height and width may help to reduce the negative impact of mowing on arthropods, our results show that mowing itself has the most substantial negative effect. Based on our results, we suggest that reduced mowing frequency, omission of mowing in parts of the grassland (refuges), or extensive grazing instead of mowing have the greatest potential to promote arthropod populations. [ABSTRACT FROM AUTHOR]

Introduction: The availability of high-quality gilthead seabream (Sparus aurata) larvae in larviculture represents a major bottleneck to the aquaculture. This challenge can be compounded by losses resulting from the emergence of a clinical disorder's symptomatology. In this study, the observed syndrome included a rotated positioning of the larval sagittal plane and in most cases leading eventually to death. Methods: Herein, we examined using amplicon sequencing of the 16S rDNA the bacterial communities associated with S. aurata larvae at different conditions (including both fish with no evidence of the syndrome and fish with syndrome) during the early developmental stages along with the contribution of rearing water, organic matter and provided feed in the microbiota during an experiment of 18 days. Results: Over the development of larvae, differences were observed in the bacterial composition between healthy and symptomatic larvae as well as between components of the system. A remarkable presence of members of the Psychrobacter genus was observed in symptomatic larvaewith a significant increase at 18dph. The healthy larvae harbor different bacterial profile with a dominance of Vibrio and Bacillus genera during 3-8dph, various members of Alphaproteobacteria during 11-14dph and Marinifilum at 18dph. The rearing water showed a different bacterial profile compared to the other components, with a slight effect of healthy larvae at 3-8dph. The bacteriome of feeds provided during the rearing of larvae was found to be diverse. Chlorella was mainly dominated by members of Firmicutes, while Rotifer and Artemia were mainly dominated bymembers of Proteobacteria including different species of Psychrobacter. At 18dph, Artemia feed seems to affect the symptomatic larvae bacteriome, where it enhanced the presence of Psychrobacter spp. Discussion: Interestingly, the comparative network analysis at 18dph indicated that the bacterial associations in symptomatic larvae were primarily driven by members of the Psychrobacter genus. While various phyla contributed to bacterial associations in healthy larvae with different frequencies including mainly members of Proteobacteria, Bacteroidota and Firmicutes phyla. Finally, the Gammaproteobacteria/Alphaproteobacteria ratio was found to be related to the health condition of larvae. This study provides valuable informationwhich can be used as indicators for monitoring the health status of S. aurata larvae. [ABSTRACT FROM AUTHOR]

This work introduces two innovative rolling pair concepts to minimize slippage and reduce mass in cam-roller systems of large-scale hydraulic drivetrains: The variable contact length and the Shifting Contact Geometry concepts. Both aim to improve traction in the low contact force phase in cyclically loaded rolling contacts. The shifting contact geometry concept was validated using three custom rolling contacts: a line contact, a double elliptical contact, and a combination of both (i.e., shifting contact geometry). The tests were conducted under synchronized cyclic loading to mimic the conditions in a hydraulic drivetrain. Furthermore, a model from previous work was implemented to make predictions and compare them against the experimental results. During preliminary tests, the double elliptical contact displayed superior tractive behavior than the line contact under the same load thanks to higher contact pressures. Under synchronized cyclic loading, the line contact displayed high sensitivity to applied resisting torques at low contact forces, leading to high slide-to-roll ratios and traction force peaks. In contrast, the rolling pair with shifting contact geometry exhibited minimum slippage even under high resisting torques, resulting in substantially lower (and in most cases negligible) slide-to-roll ratio and traction force peaks. The simulations also captured this behavior, proving the validity of the model for predicting and comparing the rolling-sliding dynamics of these two different rolling pairs. This study demonstrates that rolling pairs with shifting contact geometry can not only improve the tribological performance of cam-roller contacts in large-scale hydraulic drivetrains but also yield a more favorable dynamic behavior. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.), a vital crop for global vegetable oil production, encounters sustainability challenges in its cultivation. This study assesses the effects of incorporating a winter cover crop (CC), Avena sativa (L.), on the subsequent growth of sunflower crops and the vitality of their rhizosphere microbial communities over a two-year period. It examines the impact of two methods for suppressing winter CC--chemical suppression using glyphosate and mechanical suppression via rolling--both with and without the addition of phosphorus (P) starter fertilizer. These approaches are evaluated in comparison to the regional best management practices for sunflower cultivation, which involve a preparatory chemical fallow period and the subsequent application of starter P fertilizer. The methodology utilized Illumina sequencing for the analysis of rhizosphere bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) amplicons. Findings indicate a significant improvement (9-37%) in sunflower growth parameters (plant height, stem diameter, head diameter, and head dry weight) when cultivated after glyphosate-suppressed winter CC compared to the chemical fallows. Conversely, rolling of winter CC generally negatively affected sunflower growth. Rhizosphere bacterial communities following chemical suppression of winter CC showed greater Pielou's evenness, indicating a uniform distribution of species. In general, this treatment had more detrimental effects on beneficial sunflower rhizosphere bacteria such as Hymenobacter and Pseudarthrobacter than rolling of the winter CC, suggesting that the overall effect on sunflower growth may be mitigated by the redundancy within the bacterial community. As for fungal diversity, measured by the Chao-1 index, it increased in sunflowers planted after winter CC and receiving P fertilization, underscoring nutrient management's role in microbial community structure. Significant positive correlations between fungal diversity and sunflower growth parameters at the reproductive stage were observed (r = 0.41-0.72; p < 0.05), highlighting the role of fungal communities in plant fitness. The study underscores the positive effects of winter CC inclusion and management for enhancing sunflower cultivation while promoting beneficial microbes in the crop's rhizosphere. We advocate for strategic winter CC species selection, optimization of mechanical suppression techniques, and tailored phosphorus fertilization of sunflower to foster sustainable agriculture. [ABSTRACT FROM AUTHOR]

In this study, using an example of cold-rolled sheets, the separate effect of magnesium and zinc in an amount up to 2% upon the structure and mechanical properties of a thermally non-hardening heat-resistant alloy Al–2%Cu–1.5%Mn, the composition of which is optimized to obtain the maximum fraction of Al20Cu2Mn3 phase, is studied. It is found that in a cast state, zinc is completely contained within aluminum solid solution, and magnesium is partially included within eutectic particles of the Al2CuMg phase. These elements hardly affect the amount of Al20Cu2Mn3 phase, which is formed during deformation and heat treatment in the form of nanoscale dispersoids. It is found that addition of 1% magnesium increases the strength of cold-rolled sheets of the base alloy by 15% after 3‑hour annealing at 400 °C, without reducing the ductility. In turn, alloying with zinc does not have a significant effect on strength. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop a physical and mathematical model of the process under complex asymmetric loading in conditions of single-area and two-area deformation zone during plastic processing of medium-thickness strips. The stress state in case of loss of stability during rolling of strips of medium thickness was investigated. The patterns of changes in the stress state of the strip under conditions of reach of the limiting deformation zone, as well as the effects of plastic shaping determined by a decrease in contact stresses under conditions of increasing deformation loading, are revealed. The described method is a visual approach to assessing the stress state of a plastic medium under conditions of complex interaction and asymmetric loading. [ABSTRACT FROM AUTHOR]

In this study, intermediate rolling processes, such as warm rolling (WR) before aging, hot rolling (HR) before quenching, and a combination of these processes, were used to process 7055 and 7075 alloys with solution and aging treatment. Intermediate rolling did not change the grain structure of 7055 alloy, but it refined the grain of 7075 alloy. Moreover, it led to the formation of dislocations in the alloys, thereby promoting the precipitation of η′ phases during subsequent aging. The low cooling rate resulted in the formation of η phases with large size and high-volume fraction in HR 7055 alloy. However, intermediate rolling did not seriously coarsen the precipitates of 7075 alloy due to its low Zn + Mg content, low Zn/Mg ratio, and high density of Cr-rich phases. WR before aging enhanced the strength of 7055 alloy, but other intermediate rolling processes seriously deteriorated its mechanical properties. The strength of 7075 alloy could be enhanced by all intermediate rolling processes, and the dislocation strengthening effect in 7075 alloy was more significant than its precipitation strengthening. [ABSTRACT FROM AUTHOR]

Although low mechanical properties, Zinc (Zn) alloy systems with Copper (Cu) and Silver (Ag) as alloying elements have strong biocompatibility and biodegradability characteristics. This study examined the effects of rolling parameters and Ag alloying on the mechanical, biodegradable, and final structure of an alloy based on Zn. Comparing treated and untreated specimens, the addition of Ag led to a considerable improvement in both hardness and compressive strength. The produced alloys with varying amounts of Ag (between 1 and 4 wt%) were cold rolled at 400–800 r/min and friction coefficients between 0.3 and 0.5. The alloys' ultimate strength rose with an increase in rolling speed for Zn1Cu4Ag, and hardness and compressive strengths rose to 80HV and 470 MPa, respectively. It was demonstrated that rolling force rose somewhat with Ag concentration but significantly increased with rolling speed and friction. E. Coli and S. aureus were used to assess the biodegradable alloys' antibacterial properties. For the Zn-1Cu-2Ag alloy, the inclusion of Ag resulted in a considerable (50%) rise in antibacterial activity that exceeded the effects seen in other alloy systems. [ABSTRACT FROM AUTHOR]

Tibiofemoral slip velocity is a key contributor to total knee arthroplasty (TKA) component wear, yet few studies have evaluated this quantity in vivo. The aim of the present study was to measure and compare tibiofemoral slip velocities in 3 TKA designs for a range of daily activities. Mobile biplane X-ray imaging was used to measure 6-degree-of-freedom tibiofemoral kinematics and the locations of articular contact in 75 patients implanted with a posterior-stabilized, cruciate-retaining, or medial-stabilized design while each patient performed level walking, step up, step down, sit-to-stand, and stand-to-sit. Using these data, tibiofemoral slip velocity was calculated for the duration of each activity for each TKA design. The pattern of tibiofemoral slip velocity was similar for all 3 TKA designs within each activity but markedly different across the 5 activities tested, with the magnitude of peak slip velocity being significantly higher in level walking (range: 158–211 mm/s) than in all other activities (range: 43–75 mm/s). The pattern of tibiofemoral slip velocity in both the medial and lateral compartments closely resembled the pattern of tibiofemoral (knee) flexion angular velocity, with a strong linear relationship observed between slip velocity and flexion angular velocity (r = 0.81–0.97). Tibiofemoral slip velocity was invariant to TKA design but was significantly affected by activity type. Our measurements of slip velocity and articular contact locations for a wide range of daily activities may be used as inputs in joint simulator testing protocols and computational models developed to estimate TKA component wear. [ABSTRACT FROM AUTHOR]

For bulk material it is very well known, that the material properties differ between the material near the surface and the inner material (i.e. segregations). However, for sheet material a gradient of material properties in depth direction and its influence on forming processes was not yet investigated. Within experiments on sheet steel 1.0338 (DC04) a gradient in material properties was proven by hardness measurements for both unprocessed material as well as after conducting forming and milling processes. The characterisation shows a gradient in material hardness over the entire sheet thickness. The experimental results regarding forming processes, such as rolling and bending, additionally show an increase of the materials hardness due to work hardening. The problem from the inhomogeneous material properties leads to an inaccurate prediction of the forming behaviour of the workpiece in further processing. Machining experiments were conducted for transferring the knowledge of modified surface and subsurface layers onto forming processes and their simulation. The bending experiments and the corresponding process simulation of the spring back behaviour show, that the implementation of an inhomogeneous material property increases the prediction accuracy. Notably the prediction of the spring back behaviour of thinner sheet metals is highly improved. Therefore, an analysis of sheet metal properties in thickness direction and their consideration in forming process simulations is inevitable for the implementation of accurate material models. [ABSTRACT FROM AUTHOR]

In classical experiments, it has been found that a rigid cylinder can roll both on and under an inclined rubber plane with a friction force that depends on a power law of velocity, independent of the sign of the normal force. Further, contact area increases significantly with velocity with a related power law. We try to model qualitatively these experiments with a numerical boundary element solution with a standard linear solid and we find for sufficiently large Maugis–Tabor parameter λ qualitative agreement with experiments. However, friction force increases linearly with velocity at low velocities (like in the case with no adhesive hysteresis) and then decays at large speeds. Quantitative agreement with the Persson–Brener theory of crack propagation is found for the two power law regimes, but when Maugis–Tabor parameter λ is small, the cut-off stress in Persson–Brener theory depends on all the other dimensionless parameters of the problem. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the sea launch of a launch vehicle in low sea state, a rolling phenomenon of the launch vehicle has been observed. In rough sea conditions, launch may failure. This study utilizes dimensionality reduction-driven spatial system projection methods and virtual prototype modeling technology to reveal that the launch vehicle's rolling is caused by differences in the motion paths of the center of mass. Additionally, during the prelaunch stage, the variation in the trajectory of the launch vehicle's center of mass caused by the rolling and pitching motions of the transportation vessel has a significant impact on the roll motion of the launch vehicle. The motion in other degrees of freedom has minimal influence on the launch vehicle's rolling. The minimum rocket rolling occurs when the dynamic coefficient of friction of the launchpad–launch vehicle contact is 0.05, and the dynamic coefficient of friction of the adapters and guideways is 0.4. The conclusions provide a theoretical foundation for optimizing the sea launch system and enhancing the reliability of sea launch in rough sea conditions. [ABSTRACT FROM AUTHOR]

Every year, almost 4 million patients received medical care for knee osteoarthritis. Osteoarthritis involves progressive deterioration or degenerative changes in the cartilage, leading to inflammation and pain as the bones and ligaments are affected. To enhance treatment and surgical outcomes, various studies analyzing the biomechanics of the human skeletal system by fabricating simulated bones, particularly those reflecting the characteristics of patients with knee osteoarthritis, are underway. In this study, we fabricated replicated bones that mirror the bone characteristics of patients with knee osteoarthritis and developed a skeletal model that mimics the actual movement of the knee. To create patient-specific replicated bones, models were extracted from computerized tomography (CT) scans of knee osteoarthritis patients. Utilizing 3D printing technology, we replicated the femur and tibia, which bear the weight of the body and support movement, and manufactured cartilage capable of absorbing and dispersing the impact of knee joint loads using flexible polymers. Furthermore, to implement knee movement in the skeletal model, we developed artificial muscles based on shape memory alloys (SMAs) and used them to mimic the rolling, sliding, and spinning motions of knee flexion. The knee movement was investigated by changing the SMA spring's position, the number of coils, and the applied voltage. Additionally, we developed a knee-joint-mimicking system to analyze the movement of the femur. The proposed artificial-skeletal-model-based knee-joint-mimicking system appears to be applicable for analyzing skeletal models of knee patients and developing surgical simulation equipment for artificial joint replacement surgery. [ABSTRACT FROM AUTHOR]

Magnesium and magnesium alloy foils have great potential for application in battery anodes, electromagnetic shielding, optics and acoustics, and biology because of their excellent specific damping, internal dissipation coefficients, magnetic and electrical conductivities, as well as high theoretical specific capacity. However, magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal structure. Preparing magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to cracks. Numerous methods have been applied to prepare magnesium alloy foils. They include warm rolling, cold rolling, accumulative roll bonding, electric plastic rolling, and on-line heating rolling. Defects of magnesium and magnesium alloy foils during preparation, such as edge cracks and breakage, are important factors for consideration. Herein, the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation, defect control, performance characterization, and application prospects. The advantages and disadvantages of different preparation methods and defect (edge cracks and breakage) mechanisms in the preparation of foils are identified. [ABSTRACT FROM AUTHOR]

The article contains experimental evaluation of technological possibilities of the wave-shaped profiles and confirmation of classical metal flow on profiles of wheel rims with toroidal flanges. The following parameters are recorded during the experiments: temperature in the finishing gauge, rolling force in the 2nd, 4th, 6th and 7th passes, current, voltages and motor speeds. The analysis of experimental data of rolling profiles 7.0-20-03, 8.5-20-03 and 228G-020-01 shows that technological capabilities of special rolled products for the truck wheel rims with wavy central part are much higher than serial profiles, where the central zone is of rectangular shape. It is possible to reduce the mass of profiles without changing the process parameters, i.e., rolling force and torque. This indicates the influence of additional and kinematic effects on the deformation zone in real production conditions. [ABSTRACT FROM AUTHOR]

The production of homogeneous Ti–10Nb–(1–3)Mo (at %) alloys in the form of semifinished products (plates) was studied through multiple remeltings and homogenization annealing. Metallographic studies of the resulting materials in cast, rolled, and annealed states were carried out. The effect of annealing and composition on the structure, phase composition, and mechanical properties of the Ti–10Nb–(1–3)Mo alloy was revealed. Homogeneity after smelting was achieved by annealing at a temperature of 950°C for 12 h. An increase in the Mo content in the Ti–10Nb–(1–3)Mo alloy led to an increase in the strength of the alloys, while the ductility decreased. The achievement of high strength characteristics in selected alloys was associated with the development of annealing parameters after plastic deformation, namely, controlling the size of recrystallized grains and separating the α and β phases. In addition to α-Ti and β-Ti, the samples contained small amounts of ω-Ti, which led to a sharp increase in the hardness of the samples. [ABSTRACT FROM AUTHOR]

In the present work, 6063 Al alloy was subjected to cross cryo-rolling (XCR) at liquid nitrogen and room temperature for producing the ultrafine grained Al alloy. The XCR and cross room temperature rolling (XRTR) were performed by doing a reduction of 90%. The mechanical properties were investigated by measuring the hardness and tensile properties of investigated alloys. The increases in the average ultimate tensile strength (332 MPa), yield strength (300 MPa), and ductility (11.66%) of the XCR sample were observed as compared to the XRTR sample. The increase in the strength of the XCR sample was due to the extensive dislocation strengthening as compared to the XRTR sample. The increase in the ductility of the XCR sample was due to the softening mechanism dominated during the rolling. The microstructural properties were reported with the help of transmission electron microscopy (TEM), scanning electron microscopy and X-ray diffraction analysis and correlated with the mechanical properties. The TEM investigation revealed that XCR promotes the formation of heavily deformed sub-grains, dislocation tangles, and fragmented initial grains. The presence of dislocations inside the XRTR sample was low as compared to the XCR sample. It was observed that cross rolling at liquid nitrogen temperature further helped in the accumulation of a large number of dislocations and further improved the strength of 6063 Al alloy by suppressing the dislocations annihilations. [ABSTRACT FROM AUTHOR]

Ultrafine grained (UFG) material has received significant research interest due to its combination of strength and toughness when compared with its coarse-grained counterpart. In the present investigation, a distinct UFG microstructure of Al 5083 alloy fabricated through cryorolling (CR), CR followed by warm rolling (WR), and CR followed by short annealing (SA) have been subjected to salt immersion, polarization, and intergranular corrosion tests in 3.5% NaCl solution. A salt immersion test revealed that UFG structures have resistance to pitting corrosion for all conditions when compared to their coarse-grained counterpart. The presence of coarse intermetallic second phase particles leads to the formation of micro galvanic cells with matrix resulting in highly localized pitting corrosion in the solution treated (ST) material, whereas crystallographic pits along the lateral direction have been observed in deformed material. The lower values of corrosion current density (i corr = 3.640 and 3.910 μA/cm2) were observed for CR and WR conditions, respectively, than ST samples (i corr = 8.140 μA/cm2) were attributed to the presence of a higher volume fraction of low angle grain boundaries along with a high density of dislocations. SA after CR has slightly increased the corrosion current (i corr = 3.8 μA/cm2) values thereby shifting the corrosion potentials to a noble direction. [ABSTRACT FROM AUTHOR]

This work reports the evolution of "Structure, Processing, Property Correlation of Metastable β Titanium Ti-5Al-5Mo-5V-3Cr alloy" as a function of different aging temperatures (625,725 and 775 °C) for 4 h subsequent to solution heat treatment. The hot-rolled sheet was heat treated in β phase field and then water quenched. The solution heat treated in β phase field and then water quenched samples were aged at 625, 725 and 775 °C for 4 h. The hot-rolled sample shows the presence of α and β phases. The β-solution heat treated in β phase field and then water quenched sample of the alloy exhibits single β phase. The intensities of X-ray peaks are varying and β (211) peak shows the maximum intensity. The maximum intensity can be ascribed to β (211) texture. The solution heat treated in β phase field and then water quenched sample aged at 625 °C for 4 h shows the very fine hexagonal α phase precipitates as compared to the samples aged at 725 and 775 °C for 4 h. The samples aged at 725 and 775 °C for 4 h has resulted in precipitate-free zones as a result of the rejection of Mo, V, and Cr (β stabilizing elements) during nucleation and growth of α precipitates along the β grain boundaries. The Vickers hardness values of the alloy increase from solution heat treated in β phase field and then water quenched to all aging temperatures. The sample aged at 625 °C for 4 h shows the maximum hardness which is due to the presence of fine α phase precipitates. This can be ascribed to typical precipitation hardening. [ABSTRACT FROM AUTHOR]

The physical and mechanical properties and structural condition of flexible graphite foils produced by processing natural graphite with nitric acid, hydrolysis, thermal expansion of graphite and subsequent rolling were studied. The processes of obtaining materials and changing their characteristics has been thoroughly described and demonstrated. The structural transformations of graphite in the manufacture of foils were studied by X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). A decrease in the average size of the coherent scattering regions (CSR) of nanocrystallites was revealed during the transition from natural graphite to thermally expanded graphite from 57.3 nm to 20.5 nm at a temperature of 900 °C. The rolling pressure ranged from 0.05 MPa to 72.5 MPa. The thickness of the flexible graphite foils varied from 0.11 mm to 0.75 mm, the density—from 0.70 to 1.75 g/cm3. It was shown that with an increase in density within these limits, the compressibility of the graphite foil decreased from 65% to 9%, the recoverability increased from 5% to 60%, and the resiliency decreased from 10% to 6%, which is explained by the structural features of nanocrystallites. The properties' anisotropy of graphite foils was studied. The tensile strength increased with increasing density from 3.0 MPa (ρ = 0.7 g/cm3) to 14.0 MPa (ρ = 1.75 g/cm3) both in the rolling direction L and across T. At the same time, the anisotropy of physical and mechanical properties increased with an increase in density along L and T to 12% with absolute values of 14.0 MPa against 12.5 MPa at a thickness of 200 μm. Expressed anisotropy was observed along L and T when studying the misorientation angles of nanocrystallites: at ρ = 0.7 g/cm3, it was from 13.4° to 14.4° (up to 5% at the same thickness); at ρ = 1.3 g/cm3—from 11.0° to 12.8° (up to 7%); at ρ = 1.75 g/cm3—from 10.9° to 12.4° (up to 11%). It was found that in graphite foils, there was an increase in the coherent scattering regions in nanocrystallites with an increase in density from 24.8 nm to 49.6 nm. The observed effect can be explained by the coagulation of nanocrystallites by enhancing the Van der Waals interaction between the surface planes of coaxial nanocrystallites, which is accompanied by an increase in microstrains. The results obtained can help discover the mechanism of deformation of porous graphite foils. The obtained results can help discover the deformation mechanism of porous graphite foils. We assume that this will help predict the material behavior under industrial operating conditions of products based flexible graphite foils. [ABSTRACT FROM AUTHOR]

The two-dimensional motion of an object on a moving rough horizontal plane is investigated. Two cases are studied: the plane having a translational acceleration, and a rotating plane. For the first case, the motions of a point particle and a sphere are studied, and it is shown that the solution to the latter problem can be expressed in terms of the solution to the former one. Examples of constant acceleration and periodic acceleration along a fixed line, and specifically sinusoidal acceleration along a fixed line, are studied in more detail. Moreover, a situation is investigated where the friction is anisotropic, that is the friction coefficient depends on the direction of the velocity. In this situation, there may be stick–slip motions, and these are investigated in detail. For the second case, the motion of a point particle on a rough turntable is investigated. The large-time behavior of the system is studied in more detail. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper analyzes the occurrence of evenly spaced cracks on the surface of lamellar specimens of Fe-28Mn-6Si-5Cr (mass %) shape-memory alloy (SMA), during cold rolling. The specimens were hot rolled and normalized and developed cold rolling cracks with an approximate spacing of about 1.3 mm and a depth that increased with the thickness-reduction degree. At normalized specimens, X-ray diffraction patterns revealed the presence of multiple crystallographic variants of brittle α′ body-bcc martensite, which could be the cause of cold-rolling cracking. Both normalized and cold-rolled specimens were analyzed using scanning electron microscopy SEM. SEM micrographs revealed the presence of several crystallographic variants of α′-body-centered cubic (bcc) and ε hexagonal close-packed (hcp) martensite plates within a γ-face-centered cubic (fcc) austenite matrix in a normalized state. High-resolution SEM, recorded after 25% thickness reduction by cold-rolling, emphasized the ductile character of the cracks by means of an array of multiple dimples. After additional 33% cold-rolling thickness reduction, the surface of crack walls became acicular, thus revealing the fragile character of failure. It has been argued that the specimens cracked in the neutral point but preserved their integrity owing to the ductile character of γ-fcc austenite matrix. [ABSTRACT FROM AUTHOR]

The characteristics of the relaxation and recrystallization processes in pure tantalum deformed by rolling at room temperature are studied. It is established that at 800°C the recovery processes are activated and nuclei of recrystallization grains appear. After 1000°C, an activation of primary recrystallization is observed, which, after annealing at 1200°C, involves the entire material volume. It is shown that the processes of structural relaxation beginning at 800°C are accompanied by a dramatic decrease in microhardness. [ABSTRACT FROM AUTHOR]

This article investigated the formability of aluminum/copper bimetal sheets during single-point incremental forming. First, the two-layer sheets were produced by the explosive welding process; then, the rolling process was performed with 50% strain on two-layer samples. Considering the importance of examining the mechanical and metallurgical properties on the formability of the two-layer samples, the mechanical properties were first examined, including the uniaxial tensile and micro-hardness tests. Then, metallurgical tests were performed, including scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX) to investigate the fracture surface and penetration depth and an X-ray diffraction (XRD) test to check the secondary phase particles in the penetration zone of Al and Cu in five different annealing temperature conditions. Considering that the forming limit diagram (FLD) is dependent on the strain path, to study the effect of the strain path, the two-layer samples were formed by three geometries: pyramid, cone, and straight groove. Simulations of FLD by Abaqus software 6.14-4 with four different methods were studied: FLDCRT, effective strain rate (ESR), second derivation of thinning (SDT), and maximum strain rate (MSR). The results showed that the FLDCRT criterion provided a more accurate estimate of the necking time. In the following, the values of the thickness distribution were carried out by experimental and numerical methods, and the results between the methods were in good agreement. [ABSTRACT FROM AUTHOR]

Despite their complex composition, high-entropy alloys (HEAs) have a simple structure and have been extensively researched for their ability to achieve unique properties through thermo-mechanical processing (TMP). This review studies the effects of different rolling regimes and post-annealing on single and multiphase HEAs, analyzing how TMP leads to microstructural changes and improved mechanical properties. The rolling changes the shape and utilizes different mechanisms determined by the rolling temperature to strengthen the raw materials, thus affecting the HEAs' properties. The microstructural evolution of HEAs during annealing is affected by various parameters such as annealing time, annealing temperature, and heating rate, which impact the strength–ductility combination of HEAs. According to the literature, cryogenic rolling (cryo-rolling), as opposed to cold rolling, provides greater strengthening. This is due to the faster microstructural evolution kinetics in cryo-rolling. Thus, cryo-rolling enhances the strengthening by activating deformation twinning at earlier stages through the intersection of twins and more shear banding, which is preferred to microbands for HEAs with low stacking fault energy (SFE). Rolling at high temperatures is the most suitable approach for HEAs with low workability. Warm and hot rolling enable microstructure evolution through deformation mechanisms, including grain growth, recovery, recrystallization, and phase transformation based on the process temperature. The ratio of recovery to recrystallization depends on temperature and SFE, with recovery dominating in alloys with high SFE and at lower rolling temperatures, while recrystallization is more prevalent for alloys with low SFE and at higher temperatures, leading to specific ductility–strength synergy. [ABSTRACT FROM AUTHOR]

In this study, the effects of chemical composition and process routes on the microstructure and mechanical properties of high-Zn-content Al-Zn-Mg-Sc alloys were investigated. Aging led to the formation of nano-sized Zn phases in the grain interior and large Zn phases at the grain boundary (GB) or Al/Al3Sc interfaces in the Al-20Zn-0.5Mg-0.5Sc (20Zn-0.5Mg) alloy, and cold rolling before aging (Pre-CR) could accelerate this precipitation. Compared with the 20Zn-0.5Mg alloy, the Al-15Zn-1Mg-0.5Sc (15Zn-1Mg) alloy exhibited a more difficult Zn phase precipitation during aging, and only pre-CR could lead to the formation of intracrystalline Zn phases in this alloy during artificial aging. The transition of the η′ phases into η phases without coarsening of Zn phases occurred at the GB or Al/Al3Sc interfaces of the 15Zn-1Mg alloy during artificial aging. Pre-CR could improve the mechanical properties of high-Zn-content Al-Zn-Mg-Sc alloys, and the significant evolution of Zn phases in the 20Zn-0.5Mg alloy during processing in different routes conferred this alloy a wider range of mechanical properties than the 15Zn-1Mg alloy. [ABSTRACT FROM AUTHOR]

Introduction: The availability of high-quality gilthead seabream (Sparus aurata) larvae in larviculture represents a major bottleneck to the aquaculture. This challenge can be compounded by losses resulting from the emergence of a clinical disorder's symptomatology. In this study, the observed syndrome included a rotated positioning of the larval sagittal plane and in most cases leading eventually to death. Methods: Herein, we examined using amplicon sequencing of the 16S rDNA the bacterial communities associated with S. aurata larvae at different conditions (including both fish with no evidence of the syndrome and fish with syndrome) during the early developmental stages along with the contribution of rearing water, organic matter and provided feed in the microbiota during an experiment of 18 days. Results: Over the development of larvae, differences were observed in the bacterial composition between healthy and symptomatic larvae as well as between components of the system. A remarkable presence of members of the Psychrobacter genus was observed in symptomatic larvaewith a significant increase at 18dph. The healthy larvae harbor different bacterial profile with a dominance of Vibrio and Bacillus genera during 3-8dph, various members of Alphaproteobacteria during 11-14dph and Marinifilum at 18dph. The rearing water showed a different bacterial profile compared to the other components, with a slight effect of healthy larvae at 3-8dph. The bacteriome of feeds provided during the rearing of larvae was found to be diverse. Chlorella was mainly dominated by members of Firmicutes, while Rotifer and Artemia were mainly dominated bymembers of Proteobacteria including different species of Psychrobacter. At 18dph, Artemia feed seems to affect the symptomatic larvae bacteriome, where it enhanced the presence of Psychrobacter spp. Discussion: Interestingly, the comparative network analysis at 18dph indicated that the bacterial associations in symptomatic larvae were primarily driven by members of the Psychrobacter genus. While various phyla contributed to bacterial associations in healthy larvae with different frequencies including mainly members of Proteobacteria, Bacteroidota and Firmicutes phyla. Finally, the Gammaproteobacteria/Alphaproteobacteria ratio was found to be related to the health condition of larvae. This study provides valuable informationwhich can be used as indicators for monitoring the health status of S. aurata larvae. [ABSTRACT FROM AUTHOR]

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process windows. Within this work, an effort is made to closely investigate and understand the process limits caused by excessive slippage of the workpiece. Optical measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process limit. Large differences in slippage were observed, depending on the tribological system. While systems with polymer based lubricants showed excessive slippage at low stroke rates, systems using oil or no lubricant endured higher stroke rates before process limits were reached. The optical measurements revealed three major forms of slippage: successful rolling without slippage, failure due to excessive slippage at process start, and failure due to excessive slippage at around one workpiece rotation. [ABSTRACT FROM AUTHOR]

This study investigates the cold formability of twin-roll cast and rolled magnesium strips, specifically focusing on AZ31 and ZAX210 alloys. The aim is to assess the suitability of these alloys for various forming processes. The mechanical properties and formability characteristics of the strips were thoroughly examined to provide insights into their potential applications in transportation industries such as automotive and aerospace. The AZ31 and ZAX210 alloys were subjected to twin-roll casting and rolling processes to produce thin strips. The resulting strips were then evaluated for their cold formability. The results indicate that both alloys exhibit favourable cold formability. The ZAX210 alloy, in particular, demonstrates medium strengths with an average tensile strength of approximately 240 MPa at room temperature. The 0.2% proof stress values range between 136 MPa and 159 MPa, depending on the sampling direction. The total elongation values vary from 28% in the transverse direction to 32% at a 45° angle, indicating excellent ductility. Comparing the two alloys, the AZ31 alloy shows higher strengths due to its higher aluminium content. However, it also exhibits a more pronounced directional dependence of mechanical properties due to the formation of a strong basal texture during hot rolling. The transverse direction experiences reduced total elongation compared to the rolling direction, achieving only about 50% of the total elongation. The average Erichsen Index recorded for AZ31 and ZAX210 strips were 4.9 mm and 7.1 mm, respectively. The ZAX210 strip displays superior formability, which can be attributed to the fine-grained microstructure and the texture softening resulting from the weakening of the basal texture intensity and the splitting of the basal pole towards the rolling direction. In conclusion, the investigated twin-roll cast, rolled and annealed AZ31 and ZAX210 magnesium strips exhibit promising cold formability characteristics. The findings of this study contribute to the understanding of their mechanical behaviour and can guide the selection and optimisation of these alloys for various forming applications. [ABSTRACT FROM AUTHOR]

The typical and most widespread stress concentrators in the lower wing panels of aircraft are the drain holes located on the stringer vertical ribs. These are prime sources for the initiation and development of fatigue cracks, which lead to early failure of the wing structure. Therefore, improving fatigue life in these critical areas is one of the significant issues for research. Two combined methods of surface plastic treatment in the location around drain holes are discussed in this paper. Using the finite element method and ANSYS software, we created a finite element model and obtained nonlinear solution results in the case of tension in a plate with three holes. In addition, the development of residual stress due to the surface plastic treatment of the hole-adjacent areas was taken into account. In this paper, it is shown that after surface treatment of the corresponding areas of the holes, residual stress, which exceeds the yield stress for the plate material, is induced. When combined with alternative tensile stress, these reduce the amplitude of the local stresses, thus increasing the number of stress cycles before failure. The benefits of this technology were confirmed by fatigue test results, which include the fatigue failure types of the plates. Graphs showing the impact of applicable surface treatment combined methods on the number of cycles to failure were also plotted. [ABSTRACT FROM AUTHOR]

This paper studies the behavior of a transverse through defect in an ingot during complex vortex flow of metal deformed by the radial shift rolling (RSR) method. The aim of the work was to investigate the applicability of the RSR method for the deformation treatment of oxide-dispersed strengthened steel (ODS-steel) ingots into a final semi- finished product. Vortex flow of metal promotes dispersion of alloying solid oxides and refinement of steel structure. However, the question of development or closure of possible casting defects of ODS-steel ingot remains open. For this purpose, an ODS-steel ingot with a through-hole modelling the defect was rolled according to the assumed process scheme. Also, to visualize the evolution of the defect in more detail during the rolling process, a simulation of the same defect development in an aluminum bar has been performed in 2 mm steps. The results of both rolls showed good correlation. Based on many cross-sections of the experimental bars, detailed 3D models of the defect evolution were built. An average reduction of 50 % in defect volume was found. Welding of the outer areas occurs immediately, but the central areas remain unclosed, stretching proportionally with the drawing of the rod during rolling. For this reason, RSR cannot be used with large cavity defects in the axial zone, but this method is guaranteed to weld surface defects even at low reductions. [ABSTRACT FROM AUTHOR]

The solution of the elastic-plastic contact is of major importance in contact mechanics because contact damage and wear are responsible for the failure of many machine elements subjected to contact load. In many situations including gears and bearings, the load is transmitted through a small contact region, i.e. a concentrated contact, and the resulting high gradients of stress often exceed the plastic yield limit of the softer material. Plastic flow is initiated at a certain depth, resulting in modification of contact geometry and of the stress state that can lead to crack inception and propagation. Understanding the contact behaviour in the presence of plastic strains is fundamental for predicting the contact resistance. Considering the mathematical model complexity for the contact between bodies of arbitrary boundary, as well as the dissipative nature of plasticity, an analytical solution for the elastic plastic contact problem is hard to accomplish. Alongside finite element analysis, semi-analytical methods are the only existing simulation tools for the elastic-plastic contact problems. This paper extends a previously reported elastic-plastic contact solver developed by the same author, by considering friction. In the previous solver iteration, residual displacements were calculated only in the normal contact direction, thus assuming that the shear displacements are small enough to be neglected, in other words, the contact was assumed frictionless. By considering friction, a slip-stick contact process is introduced, adding a new iterative loop in which the contact pressure and shear stresses are iterated until convergence is reached. The new computer simulation tool is expected to give more realistic predictions for the elastic-plastic contact between materials with dissimilar elastic properties, in which case the shear tractions disturb the stress and displacements fields calculated for the frictionless contact case. The results are expected to contribute to a better understanding of the contact processes in the presence of both plastic strains and friction. [ABSTRACT FROM AUTHOR]

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For advanced integrated circuits semiconductor chip, the uniformity of microstructure and texture is increasingly required for copper target material of ultra-high purity (≥99.9999%). To this end, well-customized rolling and annealing routes for the raw material of Cu are highly needed. In the study, unidirectional rolling (UR) and cross rolling (CR) were utilized in processing the supplied Cu, both with 50, 70, and 90% thickness reduction, respectively. The rolled samples then underwent identical annealing at 300°C for 60 min. The rolled and recrystallized microstructure and texture were characterized by electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). Results showed that the CR samples exhibited severer grain fragmentation, more homogeneous microstructure and weaker texture than the UR samples, especially for the samples of 90% thickness reduction. Moreover, dynamically recrystallized grains were observed in both UR and CR samples with 90% thickness reduction due to the raised temperature during severe plastic deformation. Thanks to the more uniform deformation, the annealed CR samples enjoyed finer grains of more random textures than the annealed UR ones. Therefore, cross rolling is preferable for imparting Cu sputtering targets with the required uniformity. [ABSTRACT FROM AUTHOR]

The sheet-metal-forming process is crucial in manufacturing various products, including pipes, cans, and containers. Despite its significance, controlling this complex process is challenging and may lead to defects and inefficiencies. This study introduces a novel approach to monitor the sheet-metal-forming process, specifically focusing on the rolling of cans in the oil-and-gas sector. The methodology employed in this work involves the application of temporal-signal-processing and artificial-intelligence (AI) techniques for monitoring and optimizing the manufacturing process. Temporal-signal-processing techniques, such as Markov transition fields (MTFs), are utilized to transform time series data into images, enabling the identification of patterns and anomalies. synamic time warping (DTW) aligns time series data, accommodating variations in speed or timing across different rolling processes. K-medoids clustering identifies representative points, characterizing distinct phases of the rolling process. The results not only demonstrate the effectiveness of this framework in monitoring the rolling process but also lay the foundation for the practical application of these methodologies. This allows operators to work with a simpler characterization source, facilitating a more straightforward interpretation of the manufacturing process. [ABSTRACT FROM AUTHOR]

In this article, effects of annealing treatment on the evolution of microstructure, tensile properties and electrical resistivity of copper-graphene nanocomposites are investigated. In order to fabricate the nanocomposite, graphene nanopowder was ball-milled after being mixed with copper powder to form a mixture of copper-graphene powder (CuG). Hot rolled copper sheets were used as the matrix of the composite which were annealed prior to accumulative roll bonding (ARB). The nanocomposite was fabricated using 2, 4 and 6 cycles of ARB leading to 20, 40 and 160 multi-layered nanocomposites. Despite increased mechanical strength, the elongation to failure and the electrical conductivity were significantly reduced which were attributed to the high defect density after severe cold deformation and strength-ductility trade-off. The effect of cold deformation on increasing electrical resistivity was so significant that no positive effects of addition of 1% CuG on reducing resistivity was observed but a slight improvement was found in the sample with 2% CuG. However, after annealing at 500 C for 2 h, ductility was fully recovered to the initial value and the electrical resistivity was significantly reduced in the nanocomposite. This was attributed to the fact that a fully recrystallized grain structure was achieved after annealing. Percentage of reinforcing agent and the thickness of the stacking layers were found to determine the final grain size. Electrical conductivity of the nanocomposite was found to significantly improve with annealing. Indeed, the electrical conductivity of the annealed 6ARB-2%CuG composite was higher than the initially annealed copper sheet while the strength and ductility were increased, as well. This determines that the combination of ARB and annealing can be used as an effective method for fabrication of copper-graphene nanocomposites. [ABSTRACT FROM AUTHOR]

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In No. 3 hot strip mill at JFE Steel East JapanWorks (Chiba), mild steels are produced by the endless rolling process, in which rough rolled bars are joined and rolled continuously in the finishing mill. However, this process is not applied to high tensile strength steels because the alloy elements contained in those steels, such as silicon and manganese, form an oxide layer at the joining interface, disrupting the joining process. In laboratory joining tests, heating the joining surface until it melted resulted in discharge of the oxide layer from the interface, and steels that form oxide with a low melting temperature were successfully joined. A FEM flow analysis revealed that the viscosity of the oxide is the most important parameter for discharge. The low melting temperature of the oxide leads to low viscosity, resulting in the discharge of the oxide layer. [ABSTRACT FROM AUTHOR]

Multiwalled Boron Nitride Nanotubes (BNNTs) reinforced Metal Matrix Nanocomposites (MMNCs) are discussed in this work. It is noticed that the reaction of BNNTs with Aluminum (Al) to form a compound at the interface depends on the processing condition. The processing methods include sintering, solidification, rolling, High-Pressure Torsion (HPT) and heat treatment have influenced the microstructure and mechanical properties of BNNTs filled MMNCs. The review suggests that BNNTs filled MMNCs have the potential to be used in various applications. [ABSTRACT FROM AUTHOR]

During past decades, water-based and oil-in-water (O/W) based nanolubricants with nanoparticles (NPs) as additives have been developed to replace conventional oil-based lubricants for solving contamination problems during rolling processes. The formulations of nanolubricants for rolling need to be continuously improved to provide better lubrication performance. This article reviews the formulation, physicochemical properties, and lubrication mechanisms during rolling with water-based and O/W based nanolubricants, and the effects of nanolubricants on rolling force, surface roughness and oxide skin formation during rolling are discussed. This review aims to facilitate the fundamental understanding of nanolubrication and the development of rolling lubrication technology. [ABSTRACT FROM AUTHOR]

This study aims to analyze the influence of the rolling process on the microstructure and corrosion properties of the Mg/Al bimetallic bars obtained by the explosive welding method. The bars investigated were rolled using two different types of rolling: classical rolling (Variant I) and modified rolling (Variant II). Two different temperatures (300 °C and 400 °C) for each of the variables were applied as well. In this study, rods with an aluminum plating layer constituting 16.8% of the cross-sectional area and an average thickness of about 0.93 mm were investigated. Based on the revealed results, it was found that after the rolling process, the material shows clearly lower values of both icor and current in the passive range. In the joint zone of Mg/Al rods rolled at 400 °C, Al3Mg2 and Mg17Al12 intermetallic phases are distinguished, localized next to the Mg core, and characterized by columnar, coarser grains. In the transition zone closer to the Al layer, only the Al3Mg2 phase is revealed, characterized by a refined, small grain size. [ABSTRACT FROM AUTHOR]

In this study, Al-B4C/Al laminated composites with high interlayer bonding strength were fabricated by integrated hot-pressed sintering accompanied with hot rolling. The mechanical properties and interface behavior of the Al-B4C/Al laminated composites were investigated under quasi-static and impact loading. The results show that the Al-B4C/Al laminated composites obtain a high interface bonding strength, because no interlayer delamination occurs even after fractures under quasi-static and impact loads. The Al-B4C/Al laminated composites exhibit a better comprehensive mechanical performance, and the fracture can be delayed due to the high bonding strength interface. Moreover, laminated composites can absorb more impact energy than the monolithic material under impact loading due to the stress transition and relaxation. [ABSTRACT FROM AUTHOR]

The joint influence of degree and strain rate for copper and low-carbon steel is considered. A formula for calculating the average strain resistance during rolling with the joint effect of strain rate and cold-hardening is proposed. It is shown that calculating the average deformation resistance in the compression zone with joint consideration of work hardening and strain rate is more accurate. [ABSTRACT FROM AUTHOR]

Ground rolling delays spikelet initiation and thus would be expected to reduce frost injury in earlysown spring wheat. To characterize the relationship between the timing of rolling and the delay of spikelet initiation, we investigated apical development of early-sown spring wheat plants (Triticum aestivum L. cv. ‘Ayahikari’) rolled at the 1-, 2-, 3-, or 4-leaf stage in three years. All rollings delayed apical development. The delay was largest in plants treated at the 1- or 2-leaf stage: spikelet initiation by 5.0 days, the start of internode elongation by 5.5 days, and jointing by 3.5 days relative to the control. Our results and recent meteorological data suggest that in early cropping of spring wheat in the Tokai region of Japan, the earliest sowing date to avoid frost injury can be advanced by 3 days by rolling. [ABSTRACT FROM AUTHOR]

Effects of annealing treatment on microstructure, mechanical and damping properties of as-rolled ZK60 magnesium alloy sheets were examined and analyzed. The as-rolled alloy annealed at 340 °C for 1 h undergoes static recrystallization and exhibits the best combination of mechanical properties, with UTS of 333 MPa, YS of 268 MPa and El of 19%. With the strain amplitude below 4 × 10–4, the damping mechanism of the as-studied alloys can be explained by the Granato–Lüker (G–L) theory. With the strain amplitude higher than 4 × 10–4, the occurrence of micro-yield phenomenon and dislocation multiplication make the damping behavior of the alloy no longer explainable by G–L theory. The growth in damping becomes faster for all the alloys when the strain amplitude exceeds 4 × 10–4, and the alloy annealed at 340 °C for 1 h exhibits the highest damping capacity with the strain amplitude higher than 5 × 10–4 as a result of the activation of more non-basal slip systems, which will consume more elastic vibration energy and thus improve the damping capacity of the alloy. This provides a theoretical basis for the development of high-strength and high-damping magnesium alloys. [ABSTRACT FROM AUTHOR]

The temperature gradient rolling (GTR) method effectively addresses the issue of uneven deformation of surface and core in the rolling of extra-thick plate. Different from the traditional near uniform temperature rolling (UTR) process, GTR involves a significant temperature gradient along the thickness direction of the rolled piece. As a result, the rolling force prediction model used in uniform temperature rolling cannot be directly applied in GTR. Rolling force prediction model is crucial for process control models of plate mill and serves as the foundation for plate thickness control. However, there has been limited research on rolling force prediction methods specifically for GTR. In order to predict the change of rolling force in GTR process and enhance the control of the rolling process, the current paper proposed a simplified method based on the deformation resistance model, temperature distribution fitting, differential method, and loop iteration. The precision of the method was examined by using a finite element model and plane strain experiment, demonstrating a mean error between the method and FEM was less than 5%. [ABSTRACT FROM AUTHOR]

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In the present study, the influence of the processing parameters on the transformation temperatures and microstructural evolution in a copper-based shape memory alloy was investigated. Five times remelting in identical conditions was conducted to investigate the effect of successive remelting on the microstructural and thermal behavior of the alloy. Samples were hot rolled up to 25, 50, 75, and 90% reduction in thickness after heating at 900 °C. It was demonstrated that one-time remelting is required to achieve a target alloy composition. Thermal hysteresis remained almost constant with elevation in the rolling strain imposed. Furthermore, increased rolling reduction led to decreased enthalpy and entropy levels. [ABSTRACT FROM AUTHOR]