Changes In Process Parameters Research Articles

Assessment of milling condition by image processing of the produced surfaces

The digital industrial revolution calls for smart manufacturing plants, i.e. plants that include sensors and vision systems accompanied with artificial intelligence and advanced data analytics in order to meet the required accuracy, reliability and productivity levels. In this paper, we introduce a surface analysis and classification approach based on a deep learning algorithm. The approach is intended to let machining centres recognise the adequacy of process parameters adopted for the milling operation performed, based on the phenomenological effects left on the machined surface. Indeed, the operator will be able to understand how to change process parameters to improve workpiece quality of subsequent parts by a reverse engineering procedure that reconstructs the process parameters that generated the analysed surface. A shallow convolutional neural network was proposed to work on surface image patches based on a limited training dataset of optimal and undesired cutting conditions. The architecture consists of a series of 3 stacked convolutional blocks. The performance of the proposed solution was validated through 5-fold cross-validation, measuring the mean and standard deviation of the f1-score metric. The algorithm arrived at outperformed the best state-of-the-art approach by 4.8% when considering average classification performance.

Classification of metal PBF-LB parts manufactured with different process parameters using resonant ultrasound spectroscopy

To face the challenges raised by the qualification of metallic additively manufactured (AM) complex shaped and rough finish parts, non-destructive testing (NDT) volumetric methods are required. X-ray computed tomography (XCT) is presently the favored technique; however, alternative methods are needed to overcome the requirement of technical skills and the high cost of the technique. XCT also has limitations regarding the size and density of parts. Here, we propose an easy to use, fast, and efficient global NDT volumetric method based on resonant ultrasound spectroscopy (RUS) which basic principle relies on the comparative analysis of natural resonant frequency spectra of similar parts from the same family, both of which vibrating as free as possible. The methods have already proven to have the ability to sort parts with defects from flawless parts. In the present study, we demonstrate that RUS can also segregate metallic parts manufactured with different AM system process parameters. Eleven sets of three parts were manufactured, using a metal laser-powder bed fusion process, with different wall thicknesses, laser powers, scanning speeds, and scanning strategies. These parts were tested by RUS and then analyzed using the Z-score statistical method. The AM process parameter changes clearly influenced the resonance responses of the parts, and thus, the method is able to classify the different groups of parts according to their process parameters. Hence, the RUS methods can provide industries convenient tools to not only identify defective parts but to also configure AM machine parameters according to the expected and desired material properties.

THE ESTIMATION OF THE EFFECT OF COKE, OBTAINED WITH PARTICIPATION OF VOLUME-MODIFYING ADDITIVES, ON THE TECHNICAL AND ECONOMIC INDICATORS OF BLUST FURNACE SMELTING

The article deals with the effect of the coke resistance index CSR (Coke Strength after Reaction) on the technical and economic indicators of the blast furnace process. It is shown that in the production of metallurgical coke using volume-modifying additives in the amount of 0.25% by weight of the coal load, its strength improves, in particular, index CSR. As a volume-modifying additives, α-Al2O3 electrocorundum and α-SiC carborundum with a particle size of <45 μm and vibromilenum α-SiC carborundum with a particle size <12 μm were used.
 Due to the introduction of fine powders of electrocorundum and carborundum into the coal charge, the maximum increase in the coke post-reaction strength index (CSR) by 7.6% was obtained.
 The influence of changes in individual indicators of coke quality on its consumption and productivity of the blast furnace was assessed in accordance with the guidance document of the metallurgical division of Metinvest Holding LLC. This document contains a detailed methodology for use in analyzing fluctuations in specific coke consumption and throughput of blast furnaces influenced by changes in blast furnace process parameters (by factor analysis). This technique is based on quantitative relationships between changing parameters (factors) and specific coke consumption (blast furnace productivity).
 There has been made an expert technical and economic assessment of the feasibility of introducing 0.25% fine powdered α-Al2O3 and α-SiC powders into the mixture from the point of view of blast-furnace production with pulverized fuel injection technology. The results show that, despite the increase in the cost of coke with the introduction of volume-modifying additives into the mixture, a reduction in the cost of iron can be achieved due to the expected reduction in the specific consumption of coke due to an increase in its post-reaction strength.

Arc Characteristics of Ultrasonic-Magnetic Coaxial Hybrid GTAW.

Ultrasonic-magnetic field coaxial hybrid GTAW(U-M-GTAW) is a new non-melting electrode welding method proposed by combining ultrasonic assisted GTAW(U-GTAW) and magnetic assisted GTAW(M-GTAW) on the regulation characteristics of the GTAW arc. U-M-GTAW introduces ultrasonic and magnetic field effects into GTAW to improve arc characteristics. The orthogonal experiment was designed to investigate the degree of influence of different process parameters on the arc. The degree of influence of ultrasonic power P, radiator height H, magnetic field current CW, welding current CW and tungsten electrode height HT on ΔL1 (degree of arc root diameter change), ΔL2 (degree of maximum diameter change) and ΔS (degree of area change) were analyzed. In the parameter range, P has the greatest degree of influence on ΔL1 and ΔL2. As all process parameters increase, L1 shows a tendency to decrease, indicating an increase in the compression of the arc root. ΔL2 with the increase in P and CW shows a trend of first decreasing and then increasing. ΔL2 with the increase in H decreases, indicating that the acoustic radiation force increases, the arc energy increases, and the dark region decreases. The magnetic field current increases, the bottom of the arc expands, and the height of the tungsten electrode increases, the arc dispersion and thus the difference between the dark and luminous regions at the bottom increases, resulting in ΔL2 with the increase in CM and HT increases. CW has the greatest degree of influence on ΔS. ΔS decreases and then increases as P and H increase, which indicates that the force on acoustic radiation increases and then decreases in the range. An increase in the magnetic field current increases the rotation of the arc, leading to an increase in the arc area. An increase in welding current leads to an increase in arc energy, expansion of the arc morphology, and an increase in ΔS. The tungsten electrode height increases, the arc diverges, the dark region increases, the luminous area decreases, and ΔS increases. Finally, combined with the analysis of ultrasonic field and magnetic field theory, changes in process parameters will affect the force of the arc and thus the arc morphology. The U-M-GTAW arc under the action of acoustic radiation force, the plasma flow is shifted in the direction of the arc axis, and the arc contraction, under the action of magnetic field force to generate circumferential current, the arc undergoes periodic rotation, which improves GTAW arc characteristics.

Effect of Nozzle Design on the Stability and Performance of Self-Rotating Centrifugal Oil Filter

In the shadow of the oil prices, there is a need to focus on efficient and economical oil cleaning solutions. In this research study, experimental tests are carried out to evaluate the effect of nozzle position on the performance of a self-rotating centrifugal oil filter (SCOF). The nozzle size, location, and process parameters were designed for determining the rotating speed, stability, and performance of SCOF. The performance, quality, and cost were considered as the most influential parameters in the design of SCOF. Three nozzles were mounted at the top of the rotor with center distances of 33 mm, 46.5 mm, and 58.5 mm. As it is pressure-driven, it does not require any electric motor or prime mover, which conserves resources, saves cost, and helps to preserve the environment. The optimized SCOF was characterized for different oil samples for viscosity, filtration efficiency, and total base number (TBN). It was observed that the higher speed of the rotor induces a high centrifugal force which, when overcomes the viscous force of oil it cleans less than 6 µm particles. The filtration efficiency, viscosity, TBN, and stability were significantly enhanced by changes in nozzle design and process parameters in the system.

Adaptation of High-Energy Ball Milling and Heat Treatment Conditions for Improving Phase Purity of LTP-MnBi

The low-temperature phase (LTP) of MnBi is considered a viable alternative to rare earth permanent magnets. However, the synthesis of a single-phase LTP-MnBi with a specific crystallographic form is difficult because slight changes in process parameters can produce considerable variations in the crystallographic forms of the compound. In this work, a high-energy ball milling and subsequent heat treatment technique were employed to prepare highly pure LTP-MnBi. A purity of ~96 wt% of LTP-MnBi was achieved by two-stage milling and tailoring the heat treatment schedule. The effects of the heat treatment and the ball milling conditions on the magnetic performances of the material were investigated by analyzing the phase purity and the grain sizes of the sample. This high-purity LTP-MnBi exhibits the highest saturation magnetization of 63.47 emu/g, and its coercivity was measured to be 5.53 kOe.

SCENARIO PLANNING TO SUPPORT MANAGEMENT DECISIONS AT AN AGRICULTURAL ENTERPRISE

The transition to the market economy in the Russian Federation caused a sharp weakening and change in the content of the vertical components of the economic system and a disruption of the existing horizontal information flows. A specialist of an agricultural enterprise must solve the problems of forming the range and volumes of products and assess the existing and expected future market needs for these products. To do this he/she must have information about the current state of the external environment and forecasts for the future. The functioning of domestic agricultural producers under the conditions of economic sanctions applied to Russia has necessitated the rapid development of production for the purpose of import substitution. This necessitates the transformation and adaptation of agricultural enterprises to the changed external environment. In turn, this forces us to adapt the internal environment, including the use of modern management technologies, the development of progressive forms of management of agricultural enterprises. The effectiveness of the implementation of the process approach in the enterprise depends not only on the fact that the principles of process management of technological processes are used at the operational level and when planning operations. It should be noted that each change in process parameters affects the financial and economic condition of the entire enterprise. At the process control level, these changes cannot be foreseen. This explains the relevance of introducing the stage of scenario modeling to support and justify strategic decisions. The article proposes an algorithm consisting of three consecutive blocks aimed at successive diagnostics of the internal environment of the enterprise, direct design and implementation of processes and management of subsystems.

CONTROL SYSTEM OF THE TECHNOLOGICAL PROCESS OF FABRICATION SOAP

Today, it is impossible to imagine a complex, modern technological process without the use of an information and measurement system. Without such systems, it is impossible to measure the parameters of the technological process in order to make a timely decision on the need to correct the current values by influencing the technology or the processes taking place during production. Control over changes in technological process parameters is an urgent task of modern measuring equipment. A significant aspect is the maintenance of metrological reliability of such systems. The constant development of element base production technologies makes it possible to develop information and measurement systems not only with high accuracy indicators, but also with high metrological reliability. Also, the systems are becoming cheaper and any enterprise can afford them based on its needs. The primary measuring transducers in such control systems bear the greatest burden on the metrological accuracy of measurement results. This distribution of the contribution to the total measurement error on the part of the sensors imposes special requirements on their technical characteristics. The article presents the control system of the technological process of the manufacture of household soap, which is built using a modern element base, which makes it possible to measure the main parameters of the technological process (object) with high accuracy and act on the object thanks to executive devices. The need for this action is determined by comparing the current value of the monitored parameter with the set point (pre-set critical value). This procedure is performed thanks to the program loaded into the microcontroller. The article provides a structural diagram of the information and measurement system, an elemental base on the example of sensors of monitored parameters, an electrical-principle diagram, as well as an analysis of errors by measurement channels. It has been proven that measurement errors on each of the channels do not exceed the set value of 1,0 %.

Tuning Morphologies and Reactivities of Hybrid Organic-Inorganic Nanoparticles.

Hybrid nanoparticles (hNPs), or nanoparticles composed of both organic and inorganic components, hold promise for diverse energy and environmental applications due to their ability to stabilize reactive nanomaterials against aggregation, enhancing their ability to pervade tortuous spaces and travel long distances to degrade contaminants in situ. Past studies have investigated the use of polymer or surfactant coatings to stabilize nanomaterials against aggregation. However, fabrication of these materials often requires multiple steps and lacks specificity in the control of their morphologies and reactivities. Here, we demonstrated a method of producing stable hNPs with tunable morphologies by incubating polystyrene nanoparticles formed via Flash NanoPrecipitation with citrate-stabilized gold nanocatalysts. Using this simple fabrication technique, we found that gold adsorption to polystyrene nanoparticles was enabled by the presence of a good solvent for polystyrene. Furthermore, changing process parameters, such as gold incubation time, and molecular parameters, such as polymer molecular weight and end-group functionality, provided control over the resultant nanocatalyst loading and dispersal atop hNPs. We classified these morphologies into three distinct regimes─aggregated, dispersed, or internalized─and we showed that the emergence of these regimes has key implications for controlling reaction rates in applications such as heterogeneous catalysis or groundwater remediation. Specifically, we found that hNPs with gold nanocatalysts embedded below the surfaces of polystyrene nanoparticles exhibited slower bulk catalytic reduction capacity than their disperse, surface-decorated counterparts. Taken together, our work demonstrates a simple way by which hNPs can be fabricated and presents a method to control catalytic reactions using reactive nanomaterials.

Virtualization of a tube digester in alumina production

In this work, we develop a digital twin of a tube digester and a software application automatically calculating the aluminate solution quality based on mass balance equations with the purpose of improving the quality of hydro-chemical process management at the Rusal Achinsk JSC alumina plant. A mimic diagram of the nepheline sinter leaching process was visualized using the Wonderware InTouch software package. Quick scripts were created to display the process animation. The input parameters include the solution temperature, the consumption of sinter and recycled solution, as well as the chemical composition of raw materials. The air temperature, vibrations and equipment malfunction were used as the main disturbing effects. Output parameters consisted of sludge and aluminate solution yields, power consumed by the drive and the silicon ratio of the resulting solution. Based on the mass balance of sinter and recycled solution, calculated using industrial laboratory data, an algorithm for modelling variations in the digestion process and a software application for calculating the quality of aluminate solution were developed using the InTouch built-in capabilities of scripting in its own programming language. A digital twin of a tube digester was developed on the basis of an operating unit utilized at the Rusal Achinsk JSC. It was shown that the developed software application predicts the quality of the finished product (aluminate solution) using a simple balance model under variations in both the composition of raw materials (cake and recycling solution) and the rate of fed raw materials, as well as present the results of calculations performed using a mimic diagram of the process. Thus, the developed interface can be used to simulate various technological operations performed in a tube digestor, including solution drainage, sludge discharge and variations in the inlet flows. At the same time, it becomes possible both to observe current changes in process parameters and archive plots, as well as to select the optimal composition of raw materials to obtain an aluminate solution of higher quality.

Internal modified structure of silicon carbide prepared by ultrafast laser for wafer slicing

Silicon Carbide (SiC) is an important substrate material for electronic components due to its excellent properties. Compared with wire sawing technology, laser slicing technology is a promising method that can achieve the slicing of SiC wafers without kerf-loss. In this paper, the modified layer for SiC slicing was obtained by ultrafast laser processing inside semi-insulating SiC wafers. We studied the effect of pulse duration on the internal modification process and discussed the formation mechanism of the modified layer according to morphology and composition. The effect of laser processing parameters on the morphology of the modified layer was systematically studied as well as tensile tests were carried out on samples with different morphologies of the modified layer, which revealed the effect of the modified layer on the peeling. The results show that the increase in pulse duration favors the formation of internal modified structures, which are mainly composed of amorphous Si, amorphous C, amorphous SiC and SiC crystals. The change of process parameters will affect the type of structure and the formation of cracks in the modified layer. Only the sample with a single-crack layer was exfoliated successfully, proving that the crack morphology has an essential influence on the peeling.

Progress on New Preparation Methods, Microstructures, and Protective Properties of High-Entropy Alloy Coatings

Currently, the preparations of high-entropy alloy (HEA) coatings have developed into new methods such as thermal spraying, electrospark deposition technology, and magnetron sputtering. The microstructures and protective properties of HEA coatings prepared by different methods are bound to be different. Moreover, because HEAs have a wide range of composition systems, the difference in composition will inevitably lead to a change in process parameters and post-treatment methods, and then affect the microstructures and protective properties. This paper introduces the working mechanism of thermal spraying, electrospark deposition technology, and magnetron sputtering, compares the advantages and disadvantages of each method, and focuses on the influences of the compositions, process parameters, and post-treatment process on the microstructures and properties of the coating. Furthermore, this paper outlines the correlation between preparation methods, process parameters, microstructures, and properties, which will provide a reference for further development of the application of high-entropy alloy coatings. On this basis, the future development direction of HEA coatings is prospected.

Preparation of Al‐Dy core‐shell particles by electron beam treatment of Al powder with consequent magnetron deposition of Dy film

• A new method was proposed for coating a commercial aluminum powder by Dy. • Low-energy high-current electron-beam treatment and magnetron sputtering were used. • Surface smoothing and cleaning were detected after electron-beam refinement. • The average size of powder particles increases with the number of e-beam pulses. • Rolling and shaking of powder during the treatment causes uniformity of deposition. The paper presents a new method for coating commercial metal powders with rare‐earth elements (REE). This method consists of a two‐step treatment of a metal powder in a single vacuum cycle, namely the pulsed irradiation above the melting point by a low‐energy high‐current electron beam with subsequent magnetron sputtering of REE. This research reports the preparation of Al‐Dy core‐shell powder with an average diameter of particles of 40 µm. A powder holder system, providing rotary agitation and shaking of powder, was used to guarantee the uniform processing of each particle. It was established that electron beam irradiation leads to smoothing and cleaning the Al particles from surface oxides. With an increase in the number of pulses, the uniformity of processing increases; however, an increase in the average particle size occurs. Subsequent magnetron sputtering allows completely coating the surface of processed powder with dysprosium. The proposed method can be suitable for fabricating different metal‐REE core‐shell powders with necessary changes in processing parameters.

Application of Transformation Treatment to Commercial Low-Grade Electrical Steels under Different Processing Conditions

In this paper, two low-grade electrical steels are used to inspect the effect of initial columnar grains and final transformation treatment on the microstructure and textures. Results show that the Al and P elements, besides causing the surface oxidation or segregation, increase the critical transformation temperatures of steels, thus restricting the formation of strong {100} texture. Two-layer grain structure of typical surface-effect-induced transformation is developed in the steels without Al. The transformation textures in both steels are nearly random, which are much better than the {111} recrystallization texture or the memory type of transformation texture. The steel with initial columnar grained structure produces more {110}-oriented grains in finally transformed sheets, whereas the initial hot-rolled structure induces more {100}-oriented grains. In addition, high cold rolling reduction produces a one-layer grain structure in the final transformed sheets. It is confirmed again that the increase in final heating temperature leads to a transition from the memory type of transformation texture to surface-effect-induced transformation texture. For commercial steels containing harmful Al and P, the change in processing parameters during transformation treatment does not influence transformed structure and texture. Finally, the combined control of three stages of transformation during casting, hot rolling and final annealing is discussed.

The Effect of the Shear Flow on Columnar Crystal Growth in an Undercooled Melt

Herein, the effect of the shear flow on the growth of columnar crystals in an undercooled melt is studied. The asymptotic method is used to solve the dynamic model for the growth of a columnar crystal. The resulting asymptotic solution shows that the shear flow significantly changes the interface morphology of the columnar crystal. With the shear effect of the forced flow, the growth rate of the columnar interface increases in the shear direction of the shear flow. As the shear rate of the shear flow further increases, the interface of the columnar crystal is seriously deformed and distorted. The shear flow causes the columnar crystal in the undercooled melt to tend to evolve into smaller crystals in the initial stage of crystal growth. The analytical result provides a prediction of the formation of interface microstructures during solidification through the change of processing parameters.

The Effect of the Shear Flow on the Morphological Pattern of Particles in an Undercooled Melt

The effect of shear flow on the morphological pattern of particles in an undercooled melt is studied by using the asymptotic method. The mathematical model of the particle includes the anisotropic interface kinetic undercooling. The asymptotic solution for the mathematical model of the particle shows that shear flow in an undercooled melt intensifies the deformation and distortion of the particle in the initial stage of crystal growth. Due to the shear flow, the growth rate of the interface increases in the shear direction of the flow and strengthens the inward decay of the part of the interface induced by the anisotropic interface kinetics in the initial stage of crystal growth. As the shear rate of the flow increases, the interface of the particle is seriously deformed and distorted until it breaks into smaller particles. The analytical result provides the prediction of the formation of interface microstructures during solidification through the change of processing parameters.

Predicting Spray Dried Dispersion Particle Size Via Machine Learning Regression Methods

Spray dried dispersion particle size is a critical quality attribute that impacts bioavailability and manufacturability of the spray drying process and final dosage form. Substantial experimentation has been required to relate formulation and process parameters to particle size with the results limited to a single active pharmaceutical ingredient (API). This is the first study that demonstrates prediction of particle size independent of API for a wide range of formulation and process parameters at pilot and commercial scale. Additionally we developed a strategy with formulation and target particle size as inputs to define a set of “first to try” process parameters. An ensemble machine learning model was created to predict dried particle size across pilot and production scale spray dryers, with prediction errors between −7.7% and 18.6% (25th/75th percentiles) for a hold-out evaluation set. Shapley additive explanations identified how changes in formulation and process parameters drove variations in model predictions of dried particle size and were found to be consistent with mechanistic understanding of the particle formation process. Additionally, an optimization strategy used the predictive model to determine initial estimates for process parameter values that best achieve a target particle size for a provided formulation. The optimization strategy was employed to estimate process parameters in the hold-out evaluation set and to illustrate selection of process parameters during scale-up. The results of this study illustrate how trained regression models can reduce the experimental effort required to create an in-silico design space for new molecules during early-stage process development and subsequent scale-up.

A Chemical Vapor Deposition Diamond Reactor for Controlled Thin‐Film Growth with Sharp Layer Interfaces

A microwave plasma reactor for diamond growth that allows for highly controllable process conditions is presented. The position of the diamond substrate within the reactor can be accurately controlled. Thus, equilibration of plasma conditions can be carried out after changes in process parameters. With this approach, sharp layer transitions among doped, undoped, and isotopically controlled diamond films can be obtained. In addition to the sample transfer, the growth temperature is maintained through a substrate heater, and a clean reactor environment is realized by a load‐lock sample exchange system. The plasma conditions are constantly monitored by optical emission spectroscopy. Using this system, the growth of nanoscopic sandwich structures is demonstrated with controlled isotopic ratios down to ≈10 nm thickness and N(V) layers below 50 nm are obtained on (001)‐oriented diamond. Growth rates and doping efficiencies depending on the used methane concentration are presented. Characterization with continuous‐wave optically detected magnetic resonance yields an average contrast of 4.1% per nitrogen vacancy (NV) orientation in layers with a thickness below 100 nm. Depending on the used methane concentration, surface morphology and NV doping homogeneity are influenced as observed by photoluminescence and atomic force microscopy measurements.

Pulse electrodeposition of aluminium coatings from molten salt bath; effect of processing parameters on the coatings’ corrosion and wear behaviour

ABSTRACT In this study, Al coatings were pulse electrodeposited from a molten salt electrolyte onto copper substrates. The effects of applied peak current density, pulse current frequency and duty cycle on the morphology, microstructure, corrosion behaviour and tribological properties of the coatings were investigated by scanning electron microscopy, X-ray diffraction, potentiodynamic polarisation, electrochemical impedance spectroscopy and pin-on-disc wear test methods. The results showed that the changes in processing parameters changed the morphological and microstructural features of the resulting coatings, which in turn affected their corrosion and wear behaviours. Coatings with smoother surfaces, finer crystallite size and more compact morphologies that were electrodeposited at higher applied peak current density (up to 80 mA cm−2), higher pulse current frequency (up to 50 Hz) and higher duty cycle (up to 50%) exhibited more corrosion and wear resistance than the others.

Assessing the seam strength of ultrasonically welded polyester and polypropylene spunbond nonwovens

The durability of the products such as personal protective clothes and facemasks are crucial for human health as these products prevent the spread of disease. This study aims to investigate the seam strength of ultrasonically welded spunbond nonwovens used for personal protective clothes, facemasks, diapers and determine the best welding parameters for optimum seams. For these purposes, polyester and polypropylene spunbond nonwoven fabrics with different areal weights were ultrasonically welded by changing process parameters such as vibration frequency (%-kHz) and welding pressure (bar). The welded samples were evaluated according to the standard test method for seam strength and experimental data obtained from tests were statistically assessed by generating models and regression equations. The best seam strength for polyester nonwovens with different areal weights was achieved with 80% vibration amplitude and 1 bar or 1.5 bar welding pressures. In contrast, ultrasonic welding applied with 0.5 bar welding pressure and 63% or 70% vibration amplitudes resulted in the highest seam strengths for polypropylene nonwovens.