Changes In Feed Rate Research Articles

Influence of processing variables on fabrication of AA7475/B4C/Al2O3 hybrid surface composites via FSP

The motive of this research is to fabricate AA7475/B4C/Al2O3 hybrid surface composites (HSCs) using friction stir processing (FSP) for various applications in aerospace, marine, and automotive industries. The research systematically varied key processing variables, including rotational speed (900–1300 rpm), feed rate (30–60 mm/min), and reinforcement ratios (from 30% B4C and 70% Al2O3 to 70% B4C and 30% Al2O3), to optimize responses such as ultimate tensile strength (UTS), tensile elongation (TE), and microhardness (MH). A face-centered central composite design (FCCCD) of response surface methodology (RSM) was employed to develop mathematical models correlating the input parameters with the response variables. An analysis of variance (ANOVA) was conducted to assess the effects and interactions of the processing parameters on the composite properties. A validation test confirmed the reliability of these optimal conditions. ANOVA results indicated that the tool rotational speeds had the most significant effect on the tensile, ductility, and hardness properties of the HSCs. However, changes in feed rate and reinforcement ratio had minimal impact on these properties. The study identified optimal conditions for different responses: UTS of 452.62 MPa, TE of 6.89%, and MH of 168.52 HV at a rotational speed of 1300 rpm, feed rate of 45 mm/min, and a 50:50% reinforcement ratio (50% B4C and 50% Al2O3). The HSCs fabricated at 1300 rpm, 45 mm/min, and a 50:50% reinforcement ratio exhibited significant necking before failure, leading to a ductile failure mode.

Dynamic Control Method of Improving Extreme Learning Machine Algorithm in Wood Spinning Process

<p>The precise control of the feed system of the rotary cutting machine is the key to achieving uniform thickness rotary cutting of wood on the log-core veneer lathe. The application of Improving the Extreme Learning Machine Model in the feed system can effectively solve the problem of unstable feed rate matching in traditional control methods. This study analyzed the working mechanism of log-core veneer lathe and established a kinematic model of its feed system. Using the thickness and thickness variation of the wooden board as the control results of Improving the Extreme Learning Machine Model, in order to solve the optimal weight and threshold of Improving the Extreme Learning Machine Model, this paper uses an improved particle swarm optimization algorithm to solve. Finally, in the Matlab software environment, log-core veneer lathe motion model and control model are written, and simulation experiments are conducted to verify. The results show that Improving the Extreme Learning Machine Model effectively improves the control performance of the system, with stable feed rate changes, good real-time performance, fast convergence, high control accuracy, and strong adaptability.</p> <p> </p>

Predictive Temperature Control of an Industrial Heating Process

This paper presents an approach to control the temperature of an industrial heating process where a workpiece is transported through a heating unit in order to reach a certain temperature. To control this process is challenging due to the variable and possibly abruptly changing feed rate while requiring the final workpiece temperature to be maintained at a constant value. The speed itself cannot be influenced by the control system. However, its future trajectory is known to a certain extent at runtime. A model predictive controller is presented, which is characterized by the fact that the prediction horizon is dynamically adjusted to the transportation speed, that the traveled distance of the workpiece within the horizon is constant. Moreover, the step size of the integrator is also adapted, yielding a constant number of integration steps despite large variations in velocity. Because of the special structure of the used model, the system state cannot be reused from one time step to the next and needs to be reconstructed in a receeding horizon fashion, even if the model was perfect. This is also a distinctive feature of the presented control scheme. Simulation and measurement results are provided, showing that the presented controller achieves promising results and outperforms the existing lookup-table-based controller currently in use.

ALGORITHM FOR EXPERIMENTAL INVESTIGATION OF HYDROIMPULSE DEVICE FOR STRENGTHENING PARTS BY DEFORMATION

In the field of mechanical engineering, various methods and techniques are typically employed for the manufacturing of workpieces or machine components. In this context, it becomes necessary to determine the principles of selection and conduct a techno-economic assessment of various possible manufacturing approaches. Typically, the choice of the most optimal technological approach for producing a specific component involves comparing the technological cost of different manufacturing methods. Plastic deformation finds a wide range of applications beyond just restoring shapes and surfaces. It is also used to improve the physical and mechanical properties of the metal's surface, enhance roughness, and increase corrosion resistance. Plastic deformation is often combined with methods of metal buildup, such as welding, cladding, and others, to enhance the yield strength and, consequently, the service life of components. This process significantly enhances the reliability and durability of products and structures subjected to plastic deformation and metal buildup. This article presents a study aimed at identifying patterns that arise when changing the operating parameters of a high-speed hydroimpulse device designed for the deformation strengthening of parts. The influence of adjusting the parameters of the pressure pulse generator on the device's characteristics is investigated. The compliance of the vibration loading parameters of the striker, such as amplitudes and frequencies, with the specified values is verified. The change in the frequency of pressure pulse transmission in the pressure cavity of the drive due to changes in feed rate is analyzed. The capabilities of the technical equipment of the hydroimpulse device for the deformation strengthening of parts are assessed. The compatibility of the hydroimpulse device with the technology of deformation strengthening of parts is studied. Mechanical characteristics of objects before and after processing with the hydroimpulse device are compared. Conclusions are drawn based on the obtained results.

Ramie Fiber Woven Composite: The Effect of Feedrate Variation on the Tensile Strength of the Open Hole in the Drilling

Composite with woven ramie as reinforcement is a combination of woven from hemp plant fibers with resin adhesive (matrix) which each has different characteristics, which with the combination will produce a new material with better properties. The purpose of this study is to determine the magnitude of the influence of federate variations on the tensile strength of open holes in drilling, with the test method carried out with reference to ASTM D 5766/D 5766M-02 (Standard Test Method for Open Hole Tensile Strength of Polymer Matrix Composite Laminates). The tensile test speed used is 5 mm/minute. The data taken is the maximum tensile strength when the specimen breaks. The results of this study indicate that the change in feed rate affects the tensile strength of the ramie composite. The greater the feed rate used is in grading the ramie fiber composite, the smaller the composite tensile stress value becomes. In this study, the highest tensile strength is obtained from composites with a feed rate of 0.05 mm/rev and the lowest at a feed rate of 0.15 mm/rev. The change in spindle speed also affects the magnitude of the tensile strength in the ramie composite. As with the feed rate speed, the greater the spindle speed used to grind the composite, the lower the tensile strength of the composite. In this study, the maximum tensile strength value tends to be obtained by a composite with a spindle speed of 88 rpm and the lowest at a spindle speed of 1500 rpm. This study uses the type of chisel "brad and spur" with three kinds of diameter variations. The larger the diameter of the drill chisel used, the smaller the tensile strength of the composite obtained.

Modeling stratified segregation in periodically driven granular heap flow

We present a continuum approach to model segregation of size-bidisperse granular materials in unsteady bounded heap flow as a prototype for modeling segregation in other time varying flows. In experiments, a periodically modulated feed rate produces stratified segregation like that which occurs due to intermittent avalanching, except with greater layer-uniformity and higher average feed rates. Using an advection-diffusion-segregation equation and characterizing transient changes in deposition and erosion after a feed rate change, we model stratification for varying feed rates and periods. Feed rate modulation in heap flows can create well-segregated layers, which effectively mix the deposited material normal to the free surface at lengths greater than the combined layer-thickness. This mitigates the strong streamwise segregation that would otherwise occur at larger particle-size ratios and equivalent steady feed rates and can significantly reduce concentration variation during hopper discharge. Coupling segregation, deposition and erosion is challenging but has many potential applications.

Machine Tool Equipped with a Counter Balance Feed Drive in the Z Direction with Right and Left Ball Screws and the Influence of Anisotropic Mechanical Behavior on Small-Diameter Drilling Processes

In recent years, electronic devices have become lighter, thinner, shorter, smaller, and more multifunctional, motivating micro drilling technology to become more sophisticated. To meet the demands of electronic applications, this paper proposes a drilling machine tool with a counterbalance vibration control mechanism. In this report, focusing on the timing of table feed rate changes during drilling, drilling experiments were conducted using four drilling paths while changing the table movement direction and feed rate along the machining path. The accuracy of the positions of the drilled holes and condition of the drill edge after drilling were then evaluated.

Analysis and Prediction of Roughness of Face Milled Surfaces using CAD Model

The condition for the designability and efficiency of the machining processes is that the part production process is chosen to meet the operational requirements based on the most accurate technological plans possible. One part of this is the planning of the required quality and roughness of the surfaces and achievement of the required values in the finishing. In this paper, a study on the predictability of surface roughness was performed using a CAD model based on theoretical roughness and validated by cutting experiments. The reported results show the effect of the feed rate change in face milling for two tools with different edge geometries in planes parallel to the feed direction.

Taylor cone height as a tool to understand properties of electrospun PVDF nanofibers

Formation of a stable Taylor cone is an important phenomenon during electrospinning of nanofibers for controlling nanofiber properties. Optimizing electrospinning process parameters such as solution feed rate, applied electric voltage and tip to mandrel distance, a stable Taylor cone can be achieved and by maneuvering the parameters within a certain range, the height of the cone can be controlled. Here, we study the influence of the process parameters on the height of the Taylor cone and the corresponding nanofibers produced for polyvinylidene fluoride (PVDF) using dimethylformamide (DMF) as solvent. Characterization of the produced fibers and image analysis confirmed the optimal values as 1 mL/h, 10.8 kV and 10 cm for feed rate, applied voltage and spinning distance, respectively. Observations from the study reveal that contrary to proportional variation of Taylor cone height with nanofiber diameter in case of changing feed rate and applied voltage, the relationship gets inversely proportional when tip to mandrel distance is varied.

Abstract 5478: EC-18 suppressed tumor growth and alleviated side effects caused by cisplatin in the HNSCC implantation model

Abstract Introduction: Head and neck squamous cell carcinomas (HNSCC) are very unfavorable carcinoma that lowers the quality of life. In addition, side effects associated with treatment such as oral mucositis also deteriorate enough to be classified as a disease. This study verified the synergistic antitumor effect of EC-18 (PLAG, 1-Palmitoyl-2-linoleoyl-3-acetyl-roc-glycerol) with or without cisplatin as a chemotherapy and side effects alleviation effects in the metastatic mouse oral squamous carcinoma (MOSCC) orthotopic model. Method: After inserting mouse-derived squamous oral carcinoma into the right side of the tongue (n=12), it was treated with EC-18 alone or with cisplatin for three weeks. The changes in feed rate and body weight were quantitatively verified on a 2-day interval. Changes in tumor size and oral mucositis symptoms (toluidine-blue positive) were analyzed on the sacrifice day. In addition, changes in the amount of damage-associated molecular pattern (DAMP) increased by tumor and cisplatin, and changes in related active factors were quantitatively analyzed. Result: Compared to the positive control group, the tumor size was reduced by 42% in the group treated with EC-18 alone (P<0.05). In addition, the tumor size was further reduced by 25% in the group co-treated with EC-18 and cisplatin compared to the cisplatin alone (P<0.05), and it was observed that the tumor was disappeared in 3 mice in the co-treated group. In the positive control group, feed rate and body weight gradually decreased after about 12 days. Also, in the cisplatin-treated group, feed rate and body weight decreased rapidly after six days. On the other hand, in the group treated with EC-18 alone, there was no decrease in body weight and diet, and in the treatment with cisplatin, the diet and body weight gradually recovered after 14 days. Unlike the occurrence of oral mucositis symptoms independent of tumor growth inhibition by cisplatin, simultaneous treatment with EC-18 recovered oral mucositis symptoms along with the reduction of tumor growth (P<0.05). This effect could be explained by the fact that the expression of inflammation-related factors (TNFalpha, IL-1beta, IL-6) and DAMP (HMGB1, Adenosine) were effectively controlled by EC-18 (P<0.05). Conclusion: EC-18 can effectively inhibit the growth of HNSCC and alleviate the side effects caused by existing anticancer drugs at the same time. Therefore, it can be a desirable therapy for HNSCC patients. Citation Format: Guentae KIM, Eun Young Kim, Su-Hyun Shin, Hyowon Lee, Sun Young Yoon, Kaapjoo Park, Ki-young Sohn, Jae Wha Kim. EC-18 suppressed tumor growth and alleviated side effects caused by cisplatin in the HNSCC implantation model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5478.

Research into the Impact of Spindle Speed and Feed Rate Changes on the Life of a Deep-Drilling Technology Tool

The drilling process in real production places ever-increasing demands on the length and accuracy of the holes made. The drilling of holes beyond a length-to-diameter ratio of 5–10 is called deep drilling. The aim of the research was to determine in detail the deep-drilling process input conditions, their impact on the stability of the cutting process and the degree to which the output requirements were achieved. The focus of the analysis was on how the monitored technological and physical impacts translate into achieving the required gun-drill life and the quality and dimensional accuracy of deep holes, as well as their overall impact on tool life. Based on the analysis, tests were conducted to verify the impact of individual parameters on tool life. The obtained results were then statistically evaluated and optimized. Drawing on the evaluated experimental results, solutions and procedures were proposed and implemented in the environment of a real operation. This research obtained the optimal values of the frequency of rotation and displacement to ensure maximum tool life while maintaining the efficiency of the production of drilled parts. At the same time, based on the research, a methodology and recommendations for deep-drilling technology were developed.

Thermodynamic and economic evaluation of a novel waste-to-energy design incorporating anaerobic digestion and incineration

To synergistically exploit organic waste and municipal solid waste, a novel design combining anaerobic digestion and incineration for waste-to-energy has been developed. In the proposed scheme, organic waste and municipal solid waste are processed by anaerobic digestion and incineration respectively. The biogas harvested from anaerobic digestion is utilized by a gas turbine, and then the hot exhaust of the gas turbine is taken to enhance the steam cycle of the incineration plant via steam superheating, steam reheating, feedwater heating, and air preheating. Thus, high-efficiency waste-to-energy using two kinds of waste can be achieved with fewer costs. A case study was conducted to examine the feasibility of the hybrid system, and its parameters were determined by modeling and simulation. From the aspects of thermodynamics and economics, the performance of the proposed system was evaluated under various conditions and the efficiency-boosting mechanism was investigated as well. Through the system integration, the biogas-to-electricity efficiency can reach up to 48.49% with 29.42 MW net power generated from biogas at the design point, while the net power generated from municipal solid waste remains as 6.22 MW. The dynamic payback period of the biogas-based power project is only 3.49 years, and the net present value attains 125,188.54 k$. Besides, the hybrid system performs well when the biogas feed rate changes. Therefore, the suggested design is extremely suitable and promising.

Autogenous grinding mill process control practices

This paper considers pre-requisite conditions for developing grinding mill control systems and describes the main problems of control and existing constraints. The author selected a set of grinding equipment that consists of autogenous grinding mills and ball mills. The paper considers the selected mill types as control objects. It is shown that there exists a good correlation between the mill charge and its acoustic and vibration noise. The paper examines the relationship between the level of vibroacoustic noise and the mill motor power draw and defines what can be considered an extreme dependence, as well as the conditions in which a stable operation of the automatic system can be maintained excluding the mill overload mode. The paper specifies what hardware and software means would be necessary to implement such system and describes the mill charge analyzer VAZM-1M developed by Soyuztsvetmetavtomatika that was selected for this application. The author looks at certain downsides typical of the conventional control scheme when the head mill feed rate changes as the mill motor power draw changes without allowing for changing physical and mechanical properties of the ore material. The author also considers the capability of the VAZM-1M analyzer in terms of mill load estimation accuracy. This laid the basis for developing mill protection and optimization algorithms for the AG and Ball Mill comminution circuit. The paper features a block diagram of the control algorithm and its brief description. The algorithm consists of blocks, which are responsible for the following actions: they receive key process parameters from the process control system database, check them for validity, perform initial processing and filtering; after that they analyze the trends of the measured parameters and analyze if an overload condition is probable. As decided by the mill operator, the ore flow rate can be adjusted. The paper describes a case study of running an AG mill control system on the basis of the above described algorithm and using the VAZM-1M analyzer. It is noted that this algorithm can be implemented both as an adviser for the operator and for automatic control of the mill when running in overload mode.

Study on parameters on cutting AAC by wires

Autoclaved Aerated Concrete (AAC) is a Lightweight, Load-bearing, High-insulating, Durable building product, which is produced in a wide range of sizes and strengths. AAC Blocks is lightweight and when compared to the red bricks, AAC blocks are three times lighter. AAC block is rapidly developing in Vietnam. The block has more advantages such as precast, and easy installation. AAC is produced from the common materials: lime, sand, cement and water, and a small amount of rising agent. After mixing and molding, it is then autoclaved under heat and pressure to create its unique properties. Then, the AAC block will be cut into block brick by steel wire. When cutting the ACC block, the block brick surface must be smooth so that it is unnecessary to mortar. Furthermore, the roughness of the surface must be smaller than 0.1mm to paint the wall easily. The block dimension also need high precision so that the wall will be straight when blocks are superposed. However, in this paper, the roughness of the block surface will be only researched because the roughness will decide the cost, and the dimension decide the estheticism of wall. The block is made by using steel wires to cut big AAC blocks into small blocks. Effects of processing parameters on the performance of the steel wire sawing processes are wire speed, feed rate and tension. Each parameter will affect surface quality with different effects. In addition, these parameters affect each other, which causes scratches on the AAC surface. Experiments will be made to measure the height of roughness with the change of wire speed, feed rate and tension. The best parameters will be found, which helps the AAC manufacturer to obtain the higher quality.

Experimental investigation of flow forming forces in Al7075 and Al2014 – A comparative study

Flow forming is an important cold forming process that is used for producing axisymmetric jobs. The present investigation discusses the flow forming of Al2014 and Al7075. The flow forming forces were measured in the axial, circumferential, and radial directions using a Lathe dynamometer. The impact of changes in feed and mandrel speed on flow forming forces has been analyzed. The investigation showed that the axial force is the main dominating force, followed by the radial force in both Al2014 and Al7075. The average axial force in Al7075 under the same set of conditions was around 13–20% higher than Al2014 depending on feed and mandrel speed. The present investigation also suggests the change in feed rate has higher effect in Al2014 as compared to 7075 keeping other factors as constant.

Flow field characteristics analysis of interelectrode gap in electrochemical machining of film cooling holes

Electrochemical machining (ECM) is an important method to drill film cooling holes in difficult-to-machine materials such as high-temperature nickel-based alloy. However, physical field parameters of ECM, such as flow field characteristics and temperature field distribution in the interelectrode gap, cannot be directly monitored, which makes it difficult to improve the accuracy of ECM. In this paper, the effect of processing voltage, electrolyte inlet pressure, and electrode feed rate on machining accuracy was studied through experiments. According to the gas–liquid two-phase flow theory and mathematical model of convective heat transfer, the volume fraction of hydrogen and electrolyte temperature field were simulated and analyzed by COMSOL Multiphysics software. The results indicate that the electrolyte temperature plays a dominant role in all factors affecting the processing effects when only the processing voltage or electrolyte inlet pressure changes. When only the electrode feed rate changes, volume fraction of hydrogen dominates the effects. This has guiding significance for practical production, and can improve the accuracy of ECM by controlling the temperature of the electrolyte and the volume fraction of hydrogen.

FRACTAL-BASED ANALYSIS OF THE RELATION BETWEEN TOOL WEAR AND MACHINE VIBRATION IN MILLING OPERATION

Tool wear is one of the unwanted phenomena in machining operations where tool has direct contact with the workpiece. Tool wear is an important issue in milling operation that is caused due to different parameters such as machine vibration. Tool wear shows complex structure, and machine vibration is a chaotic signal that also is complex. In this research, we analyze the correlation between tool wear and machine vibration using fractal theory. We run the experiments in which machining parameters, namely depth of cut, feed rate and spindle speed change, and accordingly analyze the variations of fractal dimension of tool wear versus the fractal dimension of machine vibration signal. Based on the obtained results, variations of complexity of tool wear are reversely correlated with the variations of complexity of vibration signal. Fractal analysis could potentially be applied to other machining operations in order to investigate the relation between tool wear and machine vibration.

3D chatter stability of high-speed micromilling by considering nonlinear cutting coefficients, and process damping

High-speed micromilling can be used to fabricate 3D complex miniature components. The regenerative chatter, which is closely related to machining geometric accuracy, surface quality and tool wear, is a very important topic in micromachining research. In order to predict the high-speed micromilling stability more comprehensively, a micromilling force model was developed, which took into account the nonlinear change of cutting coefficients caused by feed rate, and the process damping effect in the shearing-dominant regimes. The relationship between micromilling force coefficients and feed rate were researched by using the least square and regression analysis method which are suitable to fit the relationship between related variables through experimental data, and ignore the complex internal relationships. The dynamic parameters of tool-machine system were obtained by performing FEM simulation on the entire spindle-holder-tool system. The continuous change of feed rate was first considered into micromilling 3D stability model by analyzing the influence of feed rate on milling force coefficients. Finally, micromilling tests were performed on AL7075 to verify the accuracy of the stability prediction model.

Research on influence of cutting parameters on frequency characteristics of KDP surface topography

The influence of cutting parameters on the frequency characteristics of optical crystal surface has been studied. The experiment of single point diamond turning was adopted to process KDP crystal. The frequency distribution of surface profile was obtained by power spectral density. The continuous wavelet method was used to evaluate the influence of cutting depth, feed rate and spindle speed on machined surface. The results show that the frequency characteristics reflect the effects of cutting parameters on surface topography. The wavelength and amplitude of mid frequency embody the change of cutting depth and spindle speed, and the amplitude increases with the increase of cutting depth and speed. Low frequency reflects the change of feed rate, and the amplitude becomes small as feed rate decreases. High frequency is the manifestation of vibration and material anisotropy in processing. Therefore the analysis of frequency characteristics on surface topography provides a reference for selecting the optimal process parameters.

COMPLEXITY-BASED ANALYSIS OF THE RELATION BETWEEN TOOL WEAR AND MACHINE VIBRATION IN TURNING OPERATION

Tool wear is an important issue that happens in all machining operations when the tool exerts forces on the workpiece. Therefore, engineers should choose the optimum values for machining parameters and conditions to reduce the amount of tool wear and increase its life. Machine vibration is one of the factors that highly affects tool wear. Since both tool wear and machine vibration signal have complex structures, in this research we employ fractal theory to find out their relation. In this paper, we analyze the relation between tool wear and machine vibration signal in different experiments where the depth of cut, feed rate and spindle speed change. The obtained results showed that tool wear and machine vibration signal are related to each other in case of variations of depth of cut and feed rate in different experiments, where both fractal structures get more complex by the increment of these machining parameters. The obtained method of analysis in this research can be potentially applied to other machining operations in order to link the machine vibration to the structure of tool wear.