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The purpose of this paper is to study the effect of on device performance by selectively annealing ITO substrates and TPD:PVK layers of the OLED at different temperatures with a certain annealing time.

Thermal annealing was carried out on the ITO anode at different temperatures (150, 350, 500°C) with a constant time (100 min); but also before the deposition of the tris(8‐hydroxyquinolato) aluminum (Alq₃) layer, at the same time, thermal treatment was carried out on the hole transporting layers (TPD:PVK layers) at different temperatures (70, 90, 110°C), and the annealing time was 30 min. We fabricated a novel device with the structure of Al/LiF/Alq₃/TPD:PVK/NiO/ITO/Glass, and tested the sheet resistance, SEM and XRD of ITO anode after annealing, at the same we also tested the I‐V, L‐V and current efficiency characteristics of OLED.

When the TPD:PVK layers were annealed at 90°C with 30 min annealing time and ITO substrates were annealed at 350°C with a constant annealing time (100 min), we find that the OLED shows obvious performance improvement, which is attributable to the fact that annealing reduces defects and improves the interface structures of organics and organic/ITO interface. On the other hand, an annealing TPD:PVK layers would slow and even impede the transport of holes, and finally leads to more balanced electron and hole injection processes.

The paper shows that the annealing method can be used to prepare high‐performance organic light‐emitting device.

Laser-based powder bed fusion (LPBF) is a new method for forming thin-walled parts, but large cooling rates and temperature gradients can lead to large residual stresses and deformations in the part. This study aims to reduce the residual stress and deformation of thin-walled parts by a specific laser rescanning strategy.

A three-dimensional transient finite element model is established to numerically simulate the LPBF forming process of multilayer and multitrack thin-walled parts. By changing the defocus amount, the laser in situ annealing process is designed, and the optimal rescanning parameters are obtained, which are verified by experiments.

The results show that the annealing effect is related to the average surface temperature and scan time. When the laser power is 30 W and the scanning speed is 20 mm/s, the overall residual stress and deformation of the thin-walled parts are the smallest, and the in situ annealing effect is the best. When the annealing frequency is reduced to once every three layers, the total annealing time can be reduced by more than 60%.

The research results can help better understand the influence mechanism of laser in situ annealing process on residual stress and deformation in LPBF and provide guidance for reducing residual stress and deformation of LPBF thin-walled parts.

The purpose of this study is to understand how printing parameters and subsequent annealing impacts porosity and crystallinity of 3D printed polylactic acid (PLA) and how these structural characteristics impact the printed material’s tensile strength in various build directions.

Two experimental studies were used, and samples with a flat vs upright print orientation were compared. The first experiment investigates a scan of printing parameters and annealing times and temperatures above the cold crystallization temperature (T_cc) for PLA. The second experiment investigates annealing above and below T_cc at multiple points over 12 h.

Annealing above T_cc does not significantly impact the porosity but it does increase crystallinity. The increase in crystallinity does not contribute to an increase in strength, suggesting that co-crystallization across the weld does not occur. Atomic force microscopy (AFM) images show that weld interfaces between printed fibers are still visible after annealing above T_cc, confirming the lack of co-crystallization. Annealing below T_cc does not significantly impact porosity or crystallinity. However, there is an increase in tensile strength. AFM images show that annealing below T_cc reduces thermal stresses that form at the interfaces during printing and slightly “heals” the as-printed interface resulting in an increase in tensile strength.

While annealing has been explored in the literature, it is unclear how it affects porosity, crystallinity and thermal stresses in fused filament fabrication PLA and how those factors contribute to mechanical properties. This study explains how co-crystallization across weld interfaces is necessary for crystallinity to increase strength and uses AFM as a technique to observe morphology at the weld.

Fused filament fabrication (FFF) using tough poly lactic acid (PLA) was determined to be the most suited method to achieve low-cost prosthetic sockets. However, improvement in the material properties is desirable to strengthen these sockets. This study aims to evaluate annealing as a potential method to improve material properties by a heat treatment of the object after 3D printing.

Four different annealing methods and a control group were tested according to ISO standard 527–1 and ISO standard 527–2. The four annealing methods included: oven; sand; water; and glycerol annealing. Tests were performed on longitudinal and transversal 3D printed samples. Deformation was determined on 3D printed test rings.

Annealing using an oven, sand and water resulted in a significant increase in tensile strength in longitudinally 3D printed tensile test samples. However, the tensile strength was decreased in the transversally 3D printed tensile test samples. The tensile modulus had no significant increase in the longitudinally and transversally printed samples. Sand annealing resulted in the least deformation, with a shrinkage of 2.04% of inner diameter and an increase in height of 1.99% for the horizontally annealed test rings.

The annealing of prosthetic sockets is not recommended as a decrease in tensile strength in transversally printed tensile test samples was observed. More research is needed towards the strengthening of tough PLA in both print directions.

This paper fulfils the need for understanding the impact of annealing on 3D printed items intended for daily use, such as a prosthetic socket.

A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.

The purpose of this study was to conduct various heat treatments (HT) such as stress relief annealing, mill annealing, recrystallization (α + β) annealing and β annealing followed by furnace cooling (FC) that were implemented to determine the effect of these on mechanical properties and the microstructure of selective laser melted and wrought samples. The mentioned annealings have been carried out to achieve the related standards in the fabrication of surgery implants.

In this paper, based on F2924-14 ASTM standard SLM and conventionally wrought parts were prepared. Then HT was performed and different characteristics such as microstructure, mechanical properties, macro-hardness and fracture surface for selective laser melted and wrought parts were analysed.

The results show that the high cooling rate in selective laser melting (SLM) generates finer grains. Therefore, tensile strength and hardness increase along with a reduction in ductility was noticed. Recrystallization annealing appears to give the best combination of ductility, strength and hardness for selective laser melted parts, whilst for equivalent wrought samples, increasing HT temperature results in reduction of mechanical properties.

The contributions of this paper are discussing the effect of different annealing on mechanical properties and microstructural evolution based on new ASTM standards for selective laser melted samples and comparing them with wrought parts.

Ti6Al4V alloy patient-customized implants (PCI) are often fabricated using laser powder bed fusion (LPBF) and annealed to enhance the microstructural, physical and mechanical properties. This study aims to demonstrate the effects of annealing on the physio-mechanical properties to select optimal process parameters.

Test samples were fabricated using the Taguchi L9 approach by varying parameters such as laser power (LP), laser velocity (LV) and hatch distance (HD) to three levels. Physical and mechanical test results were used to optimize the parameters for fabricating as-built and annealed implants separately using Grey relational analysis. An optimized parameter set was used for fabricating biological test samples, followed by animal testing to validate the qualified parameters.

Two optimized sets of process parameters (LP = 100 W, LV = 500 mm/s and HD = 0.08 mm; and LP = 300 W, LV = 1,350 mm/s and HD = 0.08 mm) are suggested suitable for implant fabrication regardless of the inclusion of annealing in the manufacturing process. The absence of any necrosis or reaction on the local tissues after nine weeks validated the suitability of the parameter set for implants.

To help PCI manufacturers in parameter selection and to exclude annealing from the manufacturing process for faster implant delivery.

To the best of the authors’ knowledge, this is probably a first attempt that suggests LPBF parameters that are independent of inclusion of annealing in implant fabrication process.

This paper investigates the variations in electrical properties of a typical isotropic conductive adhesive (ICA) made with an epoxy‐based binder that are caused by differences in the curing conditions.

In‐situ monitoring of the various processes that were used to cure the ICA revealed that electrical conduction in the ICA specimens depends on both the high‐temperature curing conditions and the conditions during cooling to temperatures below the glass transition temperature (T_g).

The electrical resistivity of the cured ICA specimens after cooling to ambient temperature decreased with increasing degree of conversion, tending towards a convergence value that decreased with increasing curing temperature. The electrical resistivity of the specimens also varied significantly depending on the subsequent annealing process. However, the electrical resistivity achieved after annealing at temperatures above the curing temperatures clearly depended on the particular curing temperature that was used. The characteristics of the polymer structure in the adhesive binder are considered to be different, depending on the curing temperature, and this affects the electrical properties of the ICA;, i.e. the characteristics of the polymer structure obtained during the curing process affect the electrical resistance of the ICA, even after subsequent annealing processes.

This paper discusses generalities of variation in the electrical properties of ICAs during heating and cooling processes. The variation in behaviour in practice will differ depending on the type of adhesive binder in the ICA.

This paper clarifies how the electrical properties of ICAs evolve during the curing, annealing and cooling processes.

This paper aims to establish an appropriate annealing method, which is necessary for shape stability and to evaluate their potential degradation performance of 1-, 3- and 5-layer material extruded polylactic-acid specimens by enhancing their thermal and mechanical properties.

The distortion of each layered printed specimen subjected to degradation was calculated in x- and y-direction. Each layered specimen was subjected to annealing at 70°C, 80°C and 90°C for 2 h and at 80°C for 1, 4, 8 and 16 h. Thermal, molecular weight and mechanical properties were calculated using, differential scanning calorimetry, gel permeation chromatography and tensile testing machine, respectively.

In the x-direction, distortion was 16.08 mm for one-layer non-annealed printed specimens and decreased by 73% and 83% for 3- and 5-layer, respectively, while each layered non-annealed specimen subjected to degradation at 37°C for one month. Within the outlined study, annealing treatment enhances properties such as the degree of crystallinity (%χ) up to 34%, Young’s modulus (E) by 30% and ultimate tensile strength by 20% compared to the non-annealed specimens.

The future research accomplishments will be concentrated on the design, development and optimisation of degraded biomedical implants using material extrusion thin films including drug delivery system and fixation plates.

The printed thin specimens subjected to degradation were investigated. This research developed a new understanding of the effect of the annealing temperature and time on the mechanical, thermal and molecular weight properties for each layered specimen.

The purpose of this paper is to create a flight route optimization for all flights that aims to minimize the total cost consists of fuel cost, ground delay cost and air delay cost over the fixed route and free route airspaces.

Efficient usage of current available airspace capacity becomes more and more important with the increasing flight demands. The efficient capacity usage of an airspace is generally in contradiction to optimum flight efficiency of a single flight. It can only be achieved with the holistic approach that focusing all flights over mixed airspaces and their routes instead of single flight route optimization for a single airspace. In the scope of this paper, optimization methods were developed to find the best route planning for all flights considering the benefits of all flights not only a single flight. This paper is searching for an optimization to reduce the total cost for all flights in mixed airspaces. With the developed optimization models, the determination of conflict-free optimum routes and delay amounts was achieved with airway capacity and separation minimum constraints in mixed airspaces. The mathematical model and the simulated annealing method were developed for these purposes.

The total cost values for flights were minimized by both developed mathematical model and simulated annealing algorithm. With the mathematical model, a reduction in total route length of 4.13% and a reduction in fuel consumption of 3.95% was achieved in a mixed airspace. The optimization algorithm with simulated annealing has also 3.11% flight distance saving and 3.03% fuel consumption enhancement.

Although the wind condition can change the fuel consumption and flight durations, the paper does not include the wind condition effects. If the wind condition effect is considered, the shortest route may not always cause the least fuel consumption especially under the head wind condition.

The results of this paper show that a flight route optimization as a holistic approach considering the all flight demand information enhances the fuel consumption and flight duration. Because of this reason, the developed optimization model can be effectively used to minimize the fuel consumption and reduce the exhaust emissions of aircraft.

This paper develops the mathematical model and simulated annealing algorithm for the optimization of flight route over the mixed airspaces that compose of fixed and free route airspaces. Each model offers the best available and conflict-free route plan and if necessary required delay amounts for each demanded flight under the airspace capacity, airspace route structure and used separation minimum for each airspace.