bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-situ observations of dislocation recovery and low angle boundary formation in deformed aluminium
Authors: Ånes H W , van Helvoort A T J , Marthinsen K 
Published: August 2019

Abstract
An experimental study of the recovery of dislocations and low angle boundary formation in aluminium is presented. By combining in-situ annealing with orientation mapping in the transmission electron microscope, maps of geometrically necessary dislocation estimates derived from orientation measurements and subgrain formation can be quantitatively analysed. A thin foil of a commercially pure aluminium alloy cold-rolled to a true strain of ε = 2.3 and annealed in-situ in four steps of increasing temperatures from 170 °C to 560 °C was studied. An increase in the subgrain size and low angle boundary misorientation was accompanied by a halving of the dislocation density from 1.2 × 1016 m−2 to 0.6 × 1016 m−2. Limited boundary migration was observed and the increased subgrain size was attributed to the dissolution of dislocations within the low angle boundaries upon annealing.
Non-destructive texture measurement methods for centreless X-ray diffractometers in reverse modified X (CHI) mode
Authors: Mertinger V , Sepsi M , Benke M 
Published: August 2019

Abstract
Conventional X-ray diffraction-based pole figure measurements have been carried on with dedicated instrument which are accompanied with certain limitations such as sample size, geometry, and no possibility for on-site measurements. These restrictions limit the availability of texture measurements to situations in which cutting a small sample from large parts is difficult or even not allowed at all. The present paper introduces new texture measurement method developed on mobile centreless X-ray diffractometers which are originally applied for residual stress measurements. The essence of this new method, named reverse modified X mode is that it uses the data obtained by residual stress measurement to describe anisotropic characteristics, even to the determination of pole figure. Using this method, pole figures can be obtained with all the benefits of centreless diffractometers: no need for sample cutting, flexibility in case of large components with complex shapes, short measuring time and portability. The obtained pole figures are equivalent to the pole figures determined by conventional diffractometers. The presentation describes the measurement method and includes the validation with conventional pole figure measurements and provides instances of applications of the new technique.
A study of the static recrystallization behaviour of cast Alloy 825 after hot-compressions
Authors: Al-Saadi M , Sandberg F , Hulme-Smith C , Karasev A , Jönsson P G 
Published: August 2019

Abstract
The static recrystallization behaviour of a columnar and equiaxed Alloy 825 material was studied on a Gleeble-3800 thermo-simulator by single-hit compression experiments. Deformation temperatures of 1000-1200 °C, a strain of up to 0.8, a strain rate of 1s−1, and relaxation times of 30, 180, and 300 s were selected as the deformation conditions to investigate the effects of the deformation parameters on the SRX behaviour. Furthermore, the influences of the initial grain structures on the SRX behaviors were studied. The microstructural evolution was studied using optical microscopy and EBSD. The EBSD measurements showed a relaxation time of 95 % for fractional recrystallization grains, t

95
, in both structures, was less than 30 seconds at the deformation temperatures 1100 °C and 1200 °C. However, fewer than 95% of recrystallized grains recrystallized when the deformation temperature was lowered to 1000 °C. From the grain-boundary misorientation distribution in statically recrystallized samples, the fraction of high-angle grain boundaries decreased with an increasing deformation temperature from 1000 °C to 1200 °C for a given relaxation time. This was attributed to grain coarsening.
The assessment of growth kinetics in the intermetallic layers of Al-AlxNiy-Ni laminate composites
Authors: Azimi M , Toroghinejad M R , Shamanian M , Kestens L A I 
Published: August 2019

Abstract
Ni aluminides have technologically attracted much attention as oxidation protective layers on Ni-superalloys for high-temperature and harsh environments applications as well as for reinforcements in metal-matrix composites. Among the Ni aluminides, the AlNi compound exhibits the best combination of oxidation-protective characteristics and hardness; thus there is a progressive demand to produce it particularly through convenient in-situ fabrication processes. Therefore, the evaluation of growth kinetics in AlxNiy layers is of crucial importance in determining an optimum compound formation process. To this purpose, Al-Ni intermetallic laminate composites were produced through cold roll bonding and subsequent annealing of aluminum and nickel sheets. The microstructure of the intermetallic layers was investigated in order to specify the controlling mechanisms and subsequently the growth model of the different phases. The Al3Ni layer was kinetically the first to appear but started to decompose at the expense of the AlNi compound when the direct source of Al disappeared for the reactive diffusion couples. The Al3Ni layer growth was initially controlled by bulk diffusion, but then at T≥525°C was modified as a function of competition between formation and consumption, whereas the AlNi growth was governed strongly by the interfacial reaction. The time dependence of the growth rate revealed different behaviors of linear and parabolic kinetics. The overall assessment revealed a bulk diffusion-controlled growth for all of the intermetallic layers. Arrhenius parameters could be derived for the Al3Ni layer, while it was impossible for the AlNi phase because the formation of this layer was caused by a mixture of diffusion mechanism.
Simulation of deformation and static recrystallization in the stress relaxation test
Authors: Seppälä O , Pohjonen A , Ilmola J , Jokiranta A , Kaijalainen A , Somani M , Larkiola J 
Published: August 2019

Abstract
A finite element (FE) simulation model illustrating the stress relaxation test was established with the Abaqus
TM
software. The microstructural evolution of steel during relaxation includes the complex phenomena of recrystallization. While the compression introduces the planned deformation and stress into the test piece, subsequent softening relieves the stress and at the same time creates microstructural reconstitution and refinement. In this study, a model was developed to simulate the kinetics of static recrystallization taking place during holding, using a technique based on FE-simulation. The simulation results have been compared to the experimental stress relaxation data obtained on a Gleeble
TM
3800 thermo-mechanical simulator. The model can be used to estimate the recrystallization kinetics throughout the test piece. In the future, these results can be used for estimating the required rolling forces for multi-pass roughing with reasonable accuracy, for instance. The modelling methodology can be extended to other steels too, with or without microalloying additions.
The effect of Niobium on Austenite Evolution during Hot Rolling of Advanced High Strength Steel
Authors: Smith A , Vercruysse F , Petrov R , Verleysen P 
Published: August 2019

Abstract
Two AHSS steels (0.2C-2.4Mn-1.5Si with/without Nb+Cr addition) were subjected to pilot reversing mill hot rolling in 5 passes varying the finish rolling and coiling temperature. After coiling simulation, the final microstructures were characterised by the EBSD technique measurements. One sample was analysed to determine the presence and the level of Nb precipitated by TEM and chemical extraction. The austenite evolution was inferred from the measured transformation textures and reconstructed final austenite texture and microstructure. Further insights were obtained by comparing the results to a semi-empirical austenite evolution model, which predicted recrystallization behaviour and level of Nb precipitation. From the combined experimental and modelling work it was shown that Nb addition led to recrystallization inhibition via partial strain induced precipitation for this high Mn and high Si steel. Applying the austenite evolution model to a more realistic industrial hot strip rolling schedule revealed earlier Nb precipitation during hot rolling and higher strain accumulation with a finer grain size. The final Nb level in solution was lower for the industrial schedule, although a significant amount was not precipitated (two thirds of the total).
Effect of Thermomechanical Parameters on Grain Growth and Recrystallization during Grain Boundary Engineering of Austenitic Stainless Steel
Authors: Tokita Shun , Kokawa Hiroyuki , Sato Yutaka S. 
Published: August 2019

Abstract
Grain boundary engineering has been attracting attention as an effective method to prevent intergranular corrosion of austenitic stainless steel and Ni based alloys. It has been considered that grain growth and recrystallization play important role in evolution of grain boundary character distribution during thermomechanical process. However, systematic researches to examine the effect of thermomechanical process parameters on grain growth and recrystallization have not been performed. In this study, grain boundary character distribution of 304 austenitic stainless steel after thermomechanical process with various parameters was analysed by electron backscatter diffraction (EBSD). Grain boundary character distribution was mainly affected by the reduction ratio of cold rolling. Abnormal grain growth was observed in the specimen with small reduction ratio (3%). Length ratio of coincident site lattice (CSL) boundaries was drastically increased to 86% in the 3% cold rolled and annealed specimens from 67% in the base material. On the other hand, normal grain growth was observed in thermomechanical processed specimens with slightly higher reduction of cold rolling (5%). In these specimens length ratio of CSL boundaries did not exceed 80%, which is required to disconnect the random boundary networks and to improve intergranular corrosion resistance effectively. Detailed analysis of grain boundary character distribution has shown that disconnection of random boundary networks was achieved by formation of annealing twins during abnormal grain growth.
Evaluation of the kinetics of recrystallization based on scaling 1D cellular automaton by DSC measurements
Authors: Bubonyi Tamás , barkóczy Péter , Gyöngyösi Szilvia 
Published: August 2019

Abstract
There are several methods to study the kinetics of the recrystallization process. DSC measurement is one of the most effective measurement methods. Cellular automata simulations are frequently used in computational studies. Both methods give and use kinetic constants. The aim of this study to find the relation between the kinetic constants. Additionally an evaluation method is introduced based on the DSC evaluation and cellular automaton which can compute a more detailed kinetic description of recrystallization.
Limit conditions for the onset of abnormal grain growth in a homogeneous microstructure: Theory and Experiments
Authors: Abbruzzese GC 
Published: August 2019

Abstract
In previous papers it has been demonstrated that abnormal grain growth in a polycrystalline microstructure is a natural phenomenon even in the presence of an homogeneous microstructure. Namely, in a statistical sense, each portion of the material has the same grain size distribution and no local heterogeneities are involved. The only necessary condition is the presence of a grain growth inhibitor which can be represented by second phase particles (Zener Drag), homogeneously distributed as well, or by segregating atoms on the grain boundary (Atoms drag).
Considering specifically the Zener Drag effect, it can be shown that in the presence of an evolution of the restraining force ( even if extremely slow), due to Ostwald ripening or to dissolution of the particles, the corresponding grain growth process allows the grain size distribution to continuously evolve reaching a critical shape. Such peculiar shape corresponds to a “structural” instability which irreversibly determines the onset of an abnormal growth phase with a drastic change of grain growth kinetics (kinetics exponents for the mean radius largely above the canonical 0.5).
In this context the mechanism of Abnormal Grain Growth onset is discussed as a general physical phenomenon and a set of experimental data on several steels will be presented for supporting such conclusion.
Influence of a pre-deformation on the growth of titanium multicrystals
Authors: Chaubet D , Beucia W , Franciosi P , Bacroix B 
Published: August 2019

Abstract
In the present study, we have developed a new elaboration process which facilitates the growth of titanium single crystals by combining plastic strain and thermal cycling around the transition temperature. It consists in introducing a small plastic deformation into annealed specimens (like in the critical strain hardening method) before carrying out annealing cycles of only a few days under high vacuum. This method has been applied to titanium of commercial purity (CP-Ti). At the end of each cycle, samples are examined in SEM / EBSD for the characterization of grain sizes and shapes, crystallographic orientations and crystalline quality.
Our first results demonstrate that we can obtain grains bigger than one square centimetre (thickness 2mm) after a preliminary plastic deformation of 3% followed by two 2 pairs of annealing cycles (total time: 96 hours). This enhanced growth is thought to be due to the combination of two driving forces associated (i) to the energy stored within the grains during plastic strain and (ii) to the phase transformation, which acts alone in the transus cycling process. These single crystals are intended to be used to study their mechanical behaviour with the small tensile machines developed to perform in situ mechanical tests into microscopes (SEM, AFM) or diffractometers.
A continuous dynamic recrystallization model to describe the hot deformation behaviour of a Ti5553 alloy
Authors: Buzolin R H , Krumphals F , Lasnik M , Krumphals A , Poletti M C 
Published: August 2019

Abstract
A physical based model is developed to describe recrystallization phenomena of titanium alloys during hot working of the β phase. Continuous dynamic recrystallization is attributed as the restoration mechanism based on the progressive transformation of low angle boundaries (subgrains) into high angle boundaries (grains). The model describes both, the microstructure, and the flow stress evolutions during hot deformation with large strains. The microstructure is conceived as been formed by three different populations of dislocations, and high as well as low angle grain boundaries. Evolution rates of all microstructural features are determined based on the effects of generation, interaction and annihilation of dislocations during deformation due to dynamic recovery, continuous dynamic recrystallization and static recovery. Continuous dynamic recrystallization is modelled and is considered to occur homogeneously within the microstructure. The model is able to predict the formation of subgrains from a fully annealed microstructure and the progressive formation of high angle grain boundaries. The subgrain and grain sizes are also obtained as output of the model. The model was applied to describe the hot compression behaviour of a Ti5553 alloy deformed between 880°C to 920°C and strain rates from 0.001 s−1 up to 10 s−1. The model is validated with flow curves and microstructural characterisation of hot deformed, and with microstructural information of non-deformed samples. The critical strain rate increases with increasing strain rate and decreasing temperature, similar to the discontinuous dynamic recrystallization phenomenon. The model can be implemented to simulate the microstructure and predict flow stresses of titanium alloys in industrial processes.
Consideration of recrystallization modeling of γ/γ’-strengthened Ni-based superalloys at sub-solvus temperatures
Authors: Nishimoto Takashi , Okajima Takuma , Zhang Qiaofu , Gong Jiadong , Olson Greg 
Published: August 2019

Abstract
New Ni-based superalloys and methods for controlling their microstructures have recently received much investigation to further improve their high-temperature properties, sometimes via control of precipitates such as γ’ (Ni3(Al,Ti,Nb,Ta)) and γ″ (Ni3Nb). In Ni-based superalloys, fine grains favor deformability and mechanical properties; therefore, control of grain size, achieved by recrystallization, is also important. Some new studies have reported the pinning effects of coarse γ’. However, few studies have investigated modeling methods for recrystallization behaviors. Difficulties in grain size and phase distribution control have hindered fabrication by open-die forging utilizing the pinning effect of the γ#x2019; phase. Therefore, this study examines the recrystallization behaviors of Ni-based superalloys containing coarse primary γ’ precipitates and considers applicable modeling methods. The recrystallization behaviors at sub-solvus temperatures are investigated in a new Ni-based superalloy with abundant coarse γ’ precipitates. Grain growth is limited by the pinning effect of coarse γ’ and the recrystallized grain size corresponds to increasing applied strain. Dynamic and static recrystallization is promoted by high strains and high temperatures. The kinetics of the recrystallized area fraction and recrystallization grain growth influenced by the pinning effect of coarse γ’ is modeled by Zurob’s method.
Kinetics of recrystallization and grain growth in an ultra-fine grained CoCrFeNiMn-type high-entropy alloy
Authors: Klimova M V , Shaysultanov D G , Chernichenko R S , Sanin V N , Zherebtsov S V , Stepanov N D 
Published: August 2019

Abstract
A novel high entropy alloy based on the CoCrFeMnNi system with substantial amounts of Al and C was studied. After cold rolling and annealing at 973-1273 K a duplex ultra-fine grained structure composed of the recrystallized fcc grains and M23C6 and B2 particles was produced. Analysis of the coarsening behavior of grains and particles growth suggested that kinetics of both was controlled by volume diffusion. The apparent activation energy of structure coarsening during recrystallization was evaluated.
A biohybrid fly-robot interface system that performs active collision avoidance
Authors: Huang Jiaqi V , Wei Yiran , Krapp Holger G 
Published: August 2019

Abstract
We have designed a bio-hybrid fly-robot interface (FRI) to study sensorimotor control in insects. The FRI consists of a miniaturized recording platform mounted on a two-wheeled robot and is controlled by the neuronal spiking activity of an identified visual interneuron, the blowfly H1-cell. For a given turning radius of the robot, we found a proportional relationship between the spike rate of the H1-cell and the relative distance of the FRI from the patterned wall of an experimental arena. Under closed-loop conditions during oscillatory forward movements biased towards the wall, collision avoidance manoeuvres were triggered whenever the H1-cell spike rate exceeded a certain threshold value. We also investigated the FRI behaviour in corners of the arena. The ultimate goal is to enable autonomous and energy-efficient manoeuvrings of the FRI within arbitrary visual environments.
Forest loss in Brazil increases maximum temperatures within 50 km
Authors: Cohn Avery S , Bhattarai Nishan , Campolo Jake , Crompton Octavia , Dralle David , Duncan John , Thompson Sally 
Published: August 2019

Abstract
Forest cover loss in the tropics is well known to cause warming at deforested sites, with maximum temperatures being particularly sensitive. Forest loss causes warming by altering local energy balance and surface roughness, local changes that can propagate across a wide range of spatial scales. Consequently, temperature increases result from not only changes in forest cover at a site, but also by the aggregate effects of non-local forest loss. We explored such non-local warming within Brazil’s Amazon and Cerrado biomes, the region with the world’s single largest amount of forest loss since 2000. Two datasets, one consisting of in-situ air temperature observations and a second, larger dataset consisting of ATs derived from remotely-sensed observations of land surface temperature, were used to quantify changes in maximum temperature due to forest cover loss at varying length-scales. We considered undisturbed forest locations (1 km2 in extent), and forest loss trends in annuli (‘halos’), located 1–2 km, 2–4 km, 4–10 km and 10–50 km from these undisturbed sites. Our research finds significant and substantial non-local warming, suggesting that historical estimates of warming due to forest cover loss under-estimate warming or mis-attribute warming to local change, where non-local changes also influence the pattern of temperature warming.
Identification of changes mangrove areas toward shoreline changes in East Coast of Surabaya 2004-2017
Authors: Chairani C , Saraswati R , Shidiq I P A 
Published: August 2019

Abstract
Changes in the mangrove area is the crucial cause for the shoreline changes, it happens since that vegetation stores sediments which lead to accretion and if that vegetation is reduced or damaged, it will cause abrasion. This research aims to identify the changes in the mangrove area and the shoreline of the east coast of Surabaya (Purmabaya) during 2004-2017. This research uses Landsat image 7 ETM + and Landsat image 8 OLI by applying overlay method which is spatial analyzed. During 2004-2017, there was a reduction on mangrove area for 167,701 Ha and the width was increasing for 374,183 Ha. At the same time, there was an abrasion for 12,1 Ha and an accretion for 314,661 Ha. In Kalisari, the widest accretion was 233,833 Ha which was followed by the increasing width of the mangrove area, while in Keputih had the widest abrasion, 6,87 Ha. The conclusion is the changes of the mangrove area Purmabaya keep increasing likewise the shoreline changes, especially the accretion width or the increasing width which keep changing during 13 years (2004-2017).
The analysis of the need and availability of green open based on the oxygen demand in Depok City, West Java, Indonesia
Authors: Dianovita  , Siwi S E 
Published: August 2019

Abstract
The increase of population in Depok from 2015 to 2017 is from 2,106,000 people to 2,254,513 people. The population growth will impact the increasing needs of land built. One of the ecology function of green open space is as a producer of oxygen. This study is calculates the needs for green open space based on the oxygen requirements of two variables, the need for human oxygen and motorized vehicles. Then calculate the area and distribution of green open space from the SPOT image using the NDVI algorithm. Analize the availability of green open space requirements based on oxygen demands. The result with the increasing number of population and motorized vehicles, more green open space must be prepared in the city. Observation of green open space and distribution in Depok was carried out from 2015 – 2017, to find out the balance between the availability of green open space and the increase of population and motorized vehicles. The result of this study provide the advise for the government regarding the Minister of Public Works Regulation No. 5 of 2008 about Guidelines for the Provisions and Use of Green Open Space.