نشریه مهندسی مکانیک مدرس
سال بیست و سوم شماره 10 (مهر 1402)

In orthopedics, the drilling process is one of the most important steps in the preparation of medical tools and implants. Improving the performance of medical tools and implants is of great importance, because these tools and implants are used in the repair of bone and joint injuries. One of the ways to improve the efficiency of these tools and implants is to use titanium nitride nano coatings on drilling tools. This article is presented with the aim of experimental analysis and optimization of axial force in the orthopedic drilling process using a tool coated with titanium nitride nano coating by physical deposition method. The purpose of this research is to improve the performance and efficiency of this process by optimizing various parameters such as tool rotation speed, cutting depth and titanium nitride coating. For this purpose, experimental tests were conducted using the response surface method. the sensitivity analysis was also performed. The results have shown that the rotational speed, as the most effective parameter, has a lesser effect (45% effect) on the axial force in the case without nanocoating, while it shows a greater effect (73% effect) in the case with nanocoating.

Today, the machining and milling of composites is of great importance; Because composites are used in various sectors and have found great efficiency in various industries. Considering this, in this article, in order to save the cost of milling composites, the effectiveness of various parameters that affect the cutting force and tool wear, including spindle speed (rpm), feed rate (mm/rev), cutting depth (mm) and percentage of sic, has been discussed; To minimize tool wear and cutting force by creating optimal conditions. Performing a sensitivity analysis according to the regression equations of cutting force and tool wear has shown that spindle speed with 63% and the percentage of composite silicon carbide with 22% have the greatest effect on tool wear and depth of cut with 47% and advance with 23% have the greatest effect on cutting force.

Magnetorheological polishing is an optimized mechanism for accurate surface polishing. By using this structure change, the common problems of payment, such as creating the aggregate structure of abrasives, have been solved. In this regard, studying and checking process parameters will be a solution to increase efficiency and best performance. In this research, the parameters of magnetic pole rotation speed, workpiece rotation speed, turning radius, gap, and machining time have been investigated. Using the regression equation of the chipping rate, the parameters have been analyzed by a statistical sensitivity analysis using the Sobol method. The obtained results state that the rotation speed of the magnetic pole at 37% and the rotation speed of the workpiece at about 30% are considered the most effective parameters, and the turning radius at 15% and the machining gap at 16% are considered as the next parameters. Machining time is known to be the least influential parameter in this process by 1%. Based on this, the effect of time parameters on this process can be ignored.

Selective laser melting is a technology for additive manufacturing where parts are produced by melting a powder bed using a laser beam. Because the metal parts produced by this method can have complex and desired geometries, it is considered a modern method for producing electric motor parts, sensors, and other components. The iron powder used in this study is pure one. The input parameters for this method include laser power, scanning speed, and the hatches distance. The design of the experiments was performed using the Taguchi method. Although many studies have been conducted on the mechanical properties of parts produced by this method, less attention has been paid to magnetic properties. In this research, the effect of selective laser melting parameters on the force of pure iron coercivity was experimentally determined. The optimal levels of parameters for achieving the optimal value of this force were determined using signal-to-noise analysis. The main effects and interactions of the parameters were taken into account in this article. The results indicate that the optimal parameter levels for obtaining the lowest amount of coercive force include a laser power of 220 watts, scanning speed of 400 mm/s, and a hatch distance of 70 micrometers. The hatch distance and scanning speed have the most interactive effects on achieving the lowest amount of coercivity.

In this article, the kinematic and dynamic analysis of a multi-bar drum mechanism is discussed using Adams software. At first, the modeling of the mechanism is done in the catia engineering software, and then the model is entered in the Adams software. Then, by determining the appropriate joints, the initial speed is given to the mechanism and THE MOTION OF the mechanism is simulated. A kinematic analysis of the mechanism is performed and results of speed and acceleration of the joints are presented. The performed design and simulation show the effectiveness of the mechanism.

Multi-bar collapsible drum mechanisms are used in various industries such as steel factories, tire factories, etc. In this article, the analysis of a collapsible multi-bar drum mechanism and its optimization is discussed using SAM software. At first, the modeling of the collapsible mechanism is carried out in Catia, and the motion analysis and possible interferences of the mechanism are evaluated. Then the mechanism is entered and analyzed in the SAM software. In this software, the position of the joints along with their movement path is determined, and therefore, it is possible to optimize the position of the mechanism joints in order to avoid interference of the parts.

In this paper, tool and workpiece wear ratio and surface roughness in the removal process of Ti-6Al-4V by spark are modeled using fuzzy algorithm. In the machining process using a spark, a copper electrode is used as a tool and equal channel angular pressing (ECAP) process is applied to the tool. In this combined modelling the number of ECAP passes, current, spark presence time and spark absence time are used as input parameters. The evaluation and validation results of fuzzy modeling, using experimental data, show that the fuzzy algorithm is capable of modeling and establishing relationships between response variables based on input parameters with high accuracy. Therefore, by using this method, one can easily predict the response variables and avoid the need of conducting experiments that require spending a lot of time and cost.

Turn-milling is a new process that uses, turning and milling operations together, so that the tool and the work piece rotate simultaneously, for this reason, it has a wide ability in machining curved and complex surfaces. The Main subject of this research is Conducting research on the effect of changes in machining parameters, including work piece rotational speed, tool rotational speed and feed rate, on cutting parameters such as cutting force, cutting pressure, and surface finish parameters. The order and the number of experiments is designed based on the full factorial method. Experiments for each of the mentioned parameters were performed at three levels, which includes 27 tests in total. The results were analyzed with the help of Minitab software. The mentioned process was performed with a φ6 diameter end mill on a steel work piece 1.7225. As a result, increasing feed rate by three times increases the machining force by about two times and reduces the cutting pressure by about 27%, Also, the surface finish quality parameters R a  and R z  increased by 74% and 61%, respectively. The upward or downward trend of cutting forces, cutting pressure and the surface finish quality did not occur with the increase in the rotational speed of the work piece and the rotational speed of the tool, in fact, an extremum range was achieved in the increasing trend of the mentioned speeds. So that the minimum resultant force and also the cutting pressure were observed in the range of rotational speed of 950rpm of the tool and 300rpm of the work piece.

The main goal of this paper is to develop a special modular fixture system for machining and drilling parts that hold pneumatic jacks componets. This family of parts is usually made in various dimensions and sizes but with a specific geometric shape. The design requirements of the restrictions, the way of the construction process is considered as the design inputs of this system.
Positioning and clamping system have been designed, modeled and simulated for the mass production of a family of these parts with minimal changes in the manufacturing process. The results obtained from the idea of designing such restraints in machining processes show that with its help, it is possible to reduce the design and manufacturing costs of restraints for a group of parts that are similar in appearance but different in size and dimensions. It will significantly reduce and minimize the time of adjusting these equipments during the production process and will increase the productivity and circulation of products.

Composites reinforced with carbon fibers have various applications in different industries, due to their physical and mechanical properties. In this regard, multi-walled carbon nanotubes are used to strengthen the epoxy resin base, which is one of the emerging and important materials. Since machining is required to repair reinforced composite parts, in this research, the damages caused during the process should also be investigated and solutions should be provided. In this study, the delamination damage in the machining of composite parts of epoxy reinforced with carbon fibers and multi-walled carbon nanotubes has been discussed. In this regard, experiments have been conducted with a carbide end-mill at different cutting speeds and feed speeds. Then the delaminations created in these tests are studied. In the analysis of the results, by increasing the rotational speed from 500 to 2500, the amount of delamination increased by 25% and the force decreased by 87%. Also, solutions that include reducing the feed speed will have a significant effect on improving the final quality of the machined part.

The properties of metal-based composites, such as their high strength-to-weight ratio and good resistance to wear and fatigue, have caused a significant growth in their use in the aerospace, automotive, and aircraft industries. Magnesium-based composites have particularly attracted the attention of researchers in various fields, especially aerospace scientists, due to their lower density than other metal-based composite alloys such as titanium and aluminum. However, due to the presence of very abrasive reinforcing material in these materials, machining them is difficult and presents numerous challenges. Therefore, it to study the machining process of these is necessary composites and to examine the effect of the main turning parameters such as cutting speed, feed rate, and depth of cut on machining forces and surface roughness. Sobol's sensitivity analysis method was used for this purpose. Using this method, it was determined that the feed rate, cutting depth, and cutting speed have the greatest effect on the machining forces, respectively. Additionally, the feed rate has a greater effect on the surface roughness than the cutting depth and cutting speed. As the feed rate increases, the surface roughness and cutting forces increase.

Currently, dissimilar metal joining processes are receiving considerable attention in various industries. The objective is to create composite structures that are both high-strength and lightweight, ultimately reducing the weight of the final product. Researchers have recently proposed friction drilling as a new method for creating joints between dissimilar metal sheets. This innovative technique offers potential advantages in achieving the desired outcomes. In this process, metal sheets are placed on top of each other and simultaneously subjected to friction drilling. As a result, this process not only creates an effective space for tapping but also establishes a frictional joint between the two sheets. Research has shown that preheating up to 350°C can have desirable effects on reducing the gap between the two sheets in the vicinity of the created joint between aluminum and stainless steel using the above-mentioned method. In the upcoming work, the effect of preheating on tool wear in simultaneous friction drilling of aluminum sheet AA6061T6 and stainless steel AISI304L using a tungsten carbide drilling tool has been experimentally analyzed, and the findings indicate that increasing the preheating temperature up to 350°C leads to a 13.77% increase in tool adhesive wear and a 0.46% increase in tool abrasive wear.

Additive manufacturing technology has been initially dedicated to the development of small parts and prototype models. Now it is rapidly developing towards the manufacture of functional and larger components. In general, no manufacturing technology developed in the modern industrial age has the potential to transform how components are designed and manufactured as much as additive manufacturing technologies. The flexibility in additive manufacturing has caused many industries, including marine industries in every corner of the world, to seek the use and development of technology, and adopt more programs for 3D printing in the near future. By using the technology, maritime craftsmen are able to create accurate models of their products through 3D modeling software; Therefore, they will be able to make their designs better and more reliably.

In this research, the effect of parameters of cutting speed, feed rate and machining time at constant cutting depth on tool wear and its effect on the surface roughness of hardened steel 4140 and machining forces were investigated. First, 4140 steel was prepared and its hardness was increased to 45 HRC under heat treatment, and then the TCMW 16T304 H13A tool was prepared from uncoated cemented carbide for machining. The design of the experiments was carried out in a full factorial manner. The analysis of the results was done from the analysis of variance test and the graphs related to the experimental results, based on these results, the advance rate had the greatest effect on the surface roughness and machining shear force, and the machining time had the greatest effect on the machining advance force and Cutting speed also had the greatest effect on tool wear. The highest amount of tool wear was equal to 0.89 mm and the lowest amount of tool wear was equal to 0.41 mm. The best surface quality was measured as 0.372 μm and the highest surface roughness was measured as 1.154 μm. The maximum shear force was 172.7 N and the minimum shear force was 54.2 N. The maximum forward force was equal to 156.59 N and the minimum forward force was equal to 45.86 N.

The ability to predict tool wear during machining is a very important part of diagnosis, which makes it possible to replace the tool at the appropriate time. Therefore, in this research, the artificial neural network approach was used to predict tool wear. First, hardened steel 4140 was turned with uncoated cemented carbide tool TCMW 16T304 H13A and with input parameters including cutting speed, feed rate and machining time in three different levels and with constant cutting depth, and the amount of tool wear was measured. And the experimental test results were used to train and validate the artificial neural network. The optimal neural network architecture was obtained with 3 nodes in the input layer, two hidden layers with 12 and 36 nodes in the first and second hidden layers, and 1 node in the output layer to predict tool wear. The prediction values of the artificial neural network model were compared with the experimental results and the average error percentage of the validation data was calculated as 3.32%.

When working with hardened materials, it's important to control and optimize the surface roughness and machining force. To achieve this, we can use intelligent methods that are based on prediction and optimization models. In this study, an artificial neural network was used to evaluate the surface roughness and machining force of hardened steel 4140 by analyzing cutting speed, feed rate, and machining time. A full factorial method was used to carry out 27 experiments, and an uncoated cemented carbide tool TCMW 16T304 H13A was used to measure surface roughness and machining force during turning. An artificial neural network model with two hidden layers was selected as the optimal architecture for separately predicting surface roughness and machining force. The predicted values were then compared with the experimental results, and the average error percentage for validation data was calculated as 4.25% for surface roughness and 5.11% for machining force. Finally, the optimal cutting parameters were selected to minimize surface roughness and machining force.

The development of reliable numerical tools for predicting the integrity of machined surfaces is significant. This paper introduces a new customized FE model to predict the deformation during turning of electron beam fused (EBM) Ti6Al4V alloy under dry cutting. The needle microstructure and exotic nano-hardness types of materials are modeled and implemented using a user subroutine in the FE model. The developed FE model provides the possibility of predicting the microstructure (thickness of alpha lamella), the changes in nano-hardness caused by machining operations in dry conditions.

Titanium and its alloys, especially the Ti6Al4V alloy, have many uses in the aerospace and medical industries due to their unique properties. The production of Ti6Al4V alloy by additive method has been very much considered due to the characteristic of this method. But due to the fact that these parts also require final machining. As a result, it is very important to achieve optimal parameters from a faster and more economical method. In this article, simulation of cryogenic machining of EBM Ti6Al4V alloy in order to study microstructural changes. done. It was validated by comparing the experimental results and simulation of the material model. Then, using the validated FE model, the effects of shear speed on forces, thermal loads and microhardness were discussed.

In this research, an effort has been made to examine and evaluate the impactful forces on a simple and cost-effective rail system, which has been modified by the addition of a suspension system. The studied rails are part of a specialized machine designed for producing lightweight wooden components with a similar pattern. This mechanism comprises two shafts and four linear bearings, ensuring smooth and error-free sliding along the shafts. All loads and forces related to other perpendicular axes are concentrated on this rail system. Consequently, through the design and incorporation of a suspension system into this setup, the adverse effects of forces on the rails have been ameliorated and significantly reduced compared to the previous state. The influence of the suspension system on the axis has been assessed using MSC ADAMS software, with results demonstrating a substantial reduction in the range of oscillatory forces originating from machining operations on the shaft.

Achieving the required dimensional and geometrical accuracy as well as the appearance and performance quality in the production of industrial parts and the availability of interchangeability in the assembly and supply of spare parts for products has been one of the important challenges of the industry. In this research, the effect of adding axial ultrasonic vibration to the tool on the geometric accuracy of the Al6061-T6 work piece in the milling process was investigated. By analyzing the results, it was found that the presence of axial ultrasonic vibration improves the parallelism and flatness of the wall and the smoothness of the bottom surface as well as the perpendicularity of the wall with the bottom. It was also observed that a higher feed speed increases geometric deviations and surface roughness, while a higher cutting speed reduces them. By comparing the graphs, it was found that the positive effect of ultrasonic vibrations on the quality of the surface and the geometric accuracy of the work piece is more noticeable in the conditions of lower cutting speed and higher feed; That is, the condition in which we face the worst surface quality and the lowest geometric accuracy in conventional milling.

Smart materials can react to environmental changes like living organisms and adapt themselves to environmental conditions and changes such as changes in temperature, electric current, magnetic field, light, humidity, etc. Using 3D printing to process smart materials is a new approach known as 4D printing. In this research, processing, manufacturing and 3D printing of PETG-ABS in three weight percentages of 70/30, 50/50 and 30/70 were done. The results of SEM also confirmed the compatibility of these two polymers. In all PETG-ABS mixtures, a combination of sea-island and drop-matrix morphology was observed, and for the 30/70 and 30/70 blends, phase droplets dispersed in the matrix were clearly observed. The results of mechanical properties also showed that as the percentage of ABS in the mixture increases, the tensile strength increases and the elongation decreases. The results obtained from the shape memory test indicate the existence of the ability to program the shape memory property in 4D printing mixtures. As expected, the increase in the weight percentage of ABS was associated with the disorder in the recovery of the mixtures, so the mixture with 70% by weight of PETG and 30% by weight of ABS showed the most favorable shape memory properties.

In this research, processing and 3D printing of PETG-ABS- Fe 3 O 4  nanocomposites reinforced with iron oxide nanoparticles in three different weight percentages of iron oxide nanoparticles with PETG70-ABS30 polymer matrix was done. This research was carried out with the aim of strengthening the shape memory properties, thermal properties, mechanical properties and adding the ability to indirectly stimulate the background matrix through the addition of iron oxide nanoparticles. SEM images confirmed that the mixture of PETG-ABS is immiscible and adding nanoparticles does not change the compatibility and miscibility of the base polymer, and this result is consistent with the DMTA analysis was also checked and confirmed. With increasing amount of iron oxide, the tensile strength and elongation decrease, and this decrease in mechanical properties is more pronounced in the sample of 20% by weight of iron oxide compared to the sample of 10% by weight. Nevertheless, the final strength of the samples is around 25 to 32 MPa, which indicates a suitable and acceptable distribution of nanoparticles up to 15% by weight in the polymer field. By increasing the amount of iron oxide nanoparticles, the amount of shape recovery increases and the nanocomposites containing 10, 15 and 20% by weight show shape recovery of 63.77%, 88.48 and 93.33%, respectively.

In this article, the effects of changing four different input parameters such as cutting speed, feed rate, feed force in Z direction and force in Y direction on the output of tool wear in the machining process of aluminum metal base composite have been investigated. To numerically examine the influence of each parameter on the  desired composite machining process results, the E-fast sensitivity analysis procedure was used. E-fast method has a high speed in quantitative and qualitative data analysis. After conducting a sensitivity analysis, it was found that as the feed force increases in the X direction, the  tool wear increases with a significant slope. It was also observed that this parameter (feed force in  X direction) has the greatest impact on  tool wear compared to other input parameters with an amount of 88%. The parameters of feed rate, feed force in Z direction and cutting speed are effective on tool wear with negligible rates of 8%, 3% and 1%, respectively.

Endmilling is a type of machining tool for chipping the surfaces of parts, which has received attention due to its wide application in industries such as molding. Therefore, today, the need of the industry to find the optimal parameters of the process is felt so that the quality of the desired surface can be achieved. In general, the selection of effective parameters in any milling process significantly affects the surface quality of a finished part. In this research, using E-fast statistical sensitivity analysis method, the simultaneous influence of input parameters including spindle speed, depth of cut, and feed rate on the output parameter of surface roughness for the samples has been investigated quantitatively. Machining experiments have been carried out under different cutting parameters as defined in steady state conditions for the milling tool. surface roughness and vibration rate of machining with non-linear quadratic forms; It has been modeled based on the cutoff parameters and its interactions through several regression analysis methods. The results of this research showed that the spindle speed time parameter is known as the most influential parameter on the surface roughness with 67% influence. It was also observed that the feed rate parameter with 30% effect of cutting depth with 3% are known as the second and third influencing parameters on surface roughness.

Metal composites have received attention from various industries due to their excellent properties, such as a high strength-to-weight ratio and wear resistance. However, due to the presence of hard and abrasive particles, the challenges have always faced machining. Therefore, studying the effective parameters in the machining of these materials is very important. Drilling is one of the most common and widely used methods in the industry. In this study, the Response Surface Method (RSM) and Central Composite Design (CCD) were used to model, optimize, and analyze the effects of machining parameters. Aluminum composite with AL356 alloy reinforced with 25 micrometers of silicon carbide and 45 micrometers of mica mineral, as well as a 6 mm diameter carbide drill, were used for the experiments. According to the results, with an increase in the drilling speed, the drilling forces increased and the surface roughness decreased. Additionally, increasing the feed rate increased forces and surface roughness. With an increase in the volume fraction of SiC reinforcing particles, the drilling forces and surface roughness increased and decreased, respectively. By analyzing the data obtained from the experiments, the best combination of values was found to minimize the surface roughness and axial force at the same time. The best combination of parameters was found to be: a spindle speed of 1855 rpm, a feed rate of 50 mm/rev, and a weight percentage of 15% SiC

Due to the significant increase in demand for materials with new capabilities, the use of composite materials is increasing. These materials have unique properties such as high wear resistance and a high strength-to-weight ratio, and are used by engineers in various industries, particularly in the aerospace and automotive sectors. Due to the metallic nature of these materials, the machining process is an integral part in achieving the shape and properties of the final product. Among composite materials, aluminum-based composites are the most widely used in industry. In this study, a methodical was conducted, study including statistical modeling using the response surface method and deriving regression equations of the effect of spindle rotation speed, feed rate, and depth of cut on surface roughness, metal removal rate, and tool wear during machining of A359/B4C/Al2O3 matrix aluminum composite. It was found that an increase in spindle rotation speed, feed rate, and cutting depth increased metal removal. The best combination of parameters that was found to simultaneously minimize the surface roughness and maximize the metal removal rate and minimize flank wear was a spindle speed of 600 rpm, a feed rate of 0.075 mm/rev, and a cutting depth of 0.20 mm

The course of change and transformation of the generations of shipyards shows that the occurrence of an accident or the invention of new technology and advanced machine tools has caused the shipyard to change to the next generation every period. This generation change includes 5 levels so far. The difference between generations of shipyards includes three general parameters of production philosophy, production technology and factory layout. The realization and development of the first generation in the late 1940s, the second generation in the late 1960s, the third generation in the late 1980s, the realization and development of the fourth generation in the early 2000s, and the development of the fifth generation started in 2020. The most important factor in the change of generations of shipbuilding is to achieve the open index (better, cheaoer and sooner). In the research, an overview of important parameters in determining the generation of shipbuilding with advanced machine tools, such as material flow, pre-outfit workshop, block making, factory expansion, mechanization, buffer area, process line, outfitting, and vessel dimensions, have been discussed.

The industry uses SCM440 steel extensively because of its many characteristics. Nevertheless, wear and vibration are two issues that this steel may bring about. Minimum Quantity Lubricant (MQL) technology is being employed extensively as the most efficient substitution approach in pursuit of a cost-effective alternative solution. Vibrations and acoustic emission signals work well for tracking surface roughness and tool wear. It is possible to use undesirable machining factors as parameters to study the behavior of the process. Regression analysis of several factors allows for the discovery of weaknesses and vulnerabilities in the machining process. Optimizing the production process and enhancing quality are possible with the use of effective factors. The two parameters that have the biggest effects on machining quality are feed rate and cutting depth. Feed rate is known to be sensitive to surface roughness, while cutting depth is recognized to be sensitive to tool wear.

Today, the wire arc additive manufacturing process is based on gas metal arc welding as one of the electric arc fusion processes, widely used in the industry due to its high efficiency. The correct selection of input parameters directly affects the welding quality, and by controlling those parameters, the amount of welding material can be reduced, its properties can be improved, and then the efficiency of the process can be increased. In this research, the production of a composite sample with a combined electrode by gas metal arc welding (GMAW) was investigated. At first, the welding speed, voltage, and wire speed were selected by studying and checking the effective parameters of the process in the wire and arc additive manufacturing (WAAM) by gas metal arc welding. Then, in order to evaluate the effects of effective welding parameters, three three-level factors were designed by the Taguchi method in Minitab software with an L9 array-related experiment. After performing the appearance review process, tensile and microhardness tests were performed. The tensile test results showed that the highest tensile strength is 294.327 MPa in the sample with a welding speed of 86 mm/min, voltage of 32 V, and wire feeding speed of 6 m/min. The microhardness test results showed that the highest value of microhardness was 463.1 Vickers for the sample produced with a welding speed of 86 mm/min, voltage of 27 V, and wire feeding speed of 5 m/min.

Achieving optimal parameters in production processes is crucial in the military industry, as the products are highly complicated and resistant. Because there is no heat generation in the cutting area, abrasive water jet machining is a particularly popular procedure. This study looked into how input variables affected the abrasive water jet machining of rolled homogenous armour steel. The material removal rate, surface roughness, and Kerf angle regression equations were analyzed using the E-fast method of statistical sensitivity analysis. The findings demonstrated that the standoff distance, with a 74% impact, is the most effective parameter on the kerf angle, and the jet traversal speed, with a 95% and 50% impact on the material removal rate and surface roughness, respectively. In addition, pressure had the least effect on three variables of material removal rate, surface roughness and kerf angle.

In this article, the effect of creating a surface pattern on the expression of cutting has been studied. More precisely, the effect of the texture created by laser engraving on the values of machining forces was investigated in different states, and these tests were performed both in the presence of lubricant and in its absence. The parameters of depth, pitch, texture diameter and distance from Cutting edges were considered as tool texture parameters. A total of 9 experiments were conducted using the Taguchi test design method. Lubrication in both textured and non-textured tools reduced the machining force by 30-35%. In the end, the machining forces obtained from the test were compared with textured and non-textured tools in the presence of lubricant, and it was observed that due to texturing of the tool, the machining force decreased by about 28%.

One of the new and widely used polishing processes for the surfaces of cylindrical parts is the Magnetic Rotary Abrasive Polishing Process (MRAF). This process is done using magnetic force and rotational speed simultaneously and oppositely. In this process, the forces required for machining and surface polishing are applied to the surface of the workpiece through magnetic and rotational force. One of the capabilities of this process is the ability to finish the internal and external surfaces of various parts with a special geometric shape and axial symmetry. The purpose of this article is to investigate the mathematical model of the chip removal mechanism and surface roughness changes, as well as applied forces in the process, for an abrasive particle. In order to model and optimize process parameters, response surface method and analysis of variance have been used. Based on the presented mathematical model, it was observed that the parameters of rotation speed (S), working distance (w) and the dimensions of the abrasive particle (A) have a significant effect on the quality of the surface (Ra). Based on the surface response method, the lowest surface roughness value was obtained through a rotation speed of 700 rpm, a working distance of 1.5 mm and an abrasive particle with dimensions of 18 micrometers, which is equal to 43.64 nm and with the experimental value obtained from the tests, That is, 43 nm had an acceptable match and had a desirability level of 0.9959. The obtained results were in good agreement with each other in theoretical and experimental modes.

The proper operation and quality of the finished product are highly dependent on the surface roughness of parts in a variety of industries. Among the most sophisticated techniques for reducing a part's surface roughness is the magnetorheological polishing procedure. This technique uses a magnetic field and rheological materials to improve the surface roughness of items. The parameters of turning radius, gap, machining time, magnetic pole rotation speed, and workpiece rotation speed have all been studied in the present research. By applying the Sobol method for statistical sensitivity analysis, the parameters have been examined via the surface roughness regression equation. According to the results, the most effective parameters are the workpiece's rotation speed (impact of 51%) and the magnetic pole's rotation speed (impact of approximately 21%). The next parameters to be considered are the machining gap (14% impact) and machining time (11% impact). With a 3% impact, the radius of gyration is thought to be the least important parameter in this process. This means that the time parameter's impact on this procedure can be neglected.

Analyzing and modeling damage and crack growth in bodies and structures is one of the important issues in designing methods to prevent crack growth or stop it in order to avoid sudden fracture and increase the lifetime of structures. Extensive research has been performed in the field of modeling fracture, crack growth, and damage in bodies and structures. However, there are still many problems in modeling crack growth and damage in bodies with points of singularity and discontinuities. In recent years, a new theory called peridynamic has been proposed to model and analyze such problems. The formulation framework of peridynamic theory is based on integral equations. In addition, points of singularity and discontinuities and damage in the body and modeling them are another type of deformation and part of the structural equations of this theory. As a result, the peridynamic theory is used directly, without the need for additional relations to model crack growth in problems involving points of singularity and discontinuities. In this paper, a bond-based peridynamic modeling for unidirectional carbon fiber reinforced polymer material(UDCFRP) orthogonal cutting process is proposed, and the corresponding composite material bond failure criterion is also investigated for better revealing the machining mechanism of UD-CFRP machining. From comparing between simulation and experimental results, it can be indicated that the peridynamic modeling is capable for predicting the chip formation and surface crack and damages in UD-CFRP machining.

In this research, errors and accuracy of a 5-axis machine tools are investigated using a balbar device. The focus is on the measurement of positional errors and rotational errors related to rotational axes. Therefore, first, using homogeneous transformation matrices and based on the kinematic chain of machine axes, a mathematical error modeling is done for each axis in order to get an overview of the impact of errors on machine operation. In the following, a method to measure these errors is proposed, and to validate this proposed method, its results are compared with a valid method. Homogeneous transformation matrices (HTMs) are used to create a machine tool model and generate bearing error diagrams due to machine tool geometric errors based on the given experimental design. Simulated payload trajectory patterns can be used to evaluate unique fault effects for detected faults and to diagnose machine tool conditions.

This paper deals with drilling of carbon fiber reinforced polymer (CFRP) composite filled with carbon nanotube (CNT) using response surface method (RSM) based utility function. In the drilling of CFRP composites with a hybrid metal base, the additional advance force and pleat height reduce the performance of the composite. Therefore, to improve the performance of the hybrid metal matrix composite, the advancing force and the pleat height of the composite are minimized. Hence, the advancing force and pleat height are the factors considered in the present research and are the main responses that are minimized using the RSM-based utility function. Four important input factors such as drilling speed, feed rate, CNT percentage and drill helix angle are considered to analyze the performance of the drilling process. The results showed that the advance rate is a very influential parameter that affects the advance force and pleat height in hybrid metal matrix composites. During the drilling operation, due to the mutual rubbing of the CNT abrasive particles, it causes extensive surface damage such as holes, cracks, and fibers coming out. The ANOVA results show that the experimental data are well correlated at the 95% confidence interval, and this technique can be very useful and reliable for predicting drilling parameters of CFRP metal matrix composites.

The mechanical flow meter is a widely used tool in various industries such as the oil industry. A pair of oval gears is used in the mechanical flow meter. The most important issue in the oval gear is the lack of uniformity in the shape of its teeth. This lack of uniformity prevents the gears from interfering with each other, for this reason, similar to the circular gear, it is not possible to machine.  For the oval gear machining, tool design, or the use of the wire-cut method is required. As a result, it is necessary to know the profile of oval gear teeth. Therefore, in this article, the relations governing oval gears have been investigated. In these relationships, the number of teeth, geometric dimensions, and equations of motion have been investigated. Then, it was modeled using the Gear-Otix software and with the help of the results of the relationships of the gears, the interference conditions of the two gears were checked in this software, and finally, the stress analysis of the gear was done by using Comsol software for the appropriate state. With the help of the created model, it is possible to produce this gear using the wire-cut method.

When there is a need to transfer power between non-parallel shafts, bevel gears are used. Bevel gears are widely used in power transmission systems such as car differentials and helicopter gearboxes, so knowing and improving the performance of this type of gear is particularly important. It is important and necessary to accurately calculate the machining time of the desired bevel gear in order to reduce time and costs. In this paper, data are collected using Taguchi's test design method in three levels. The amount of machining time was calculated for each test, then with the help of signal-to-noise analysis, the influence of the input parameters on the design of the straight tooth bevel gear on the reduction of the machining time has been investigated. The investigated parameters are conversion ratio, allowable contact stress and allowable bending stress.According to the obtained results, the conversion ratio parameter was found to be the most effective parameter on reducing the machining time. The optimal value of the conversion ratio was reported at level 1 with a value of 1.5.

One of the components of the MAF process is the magnetic field that is applied through the field source. This source can be permanent or electrical. In terms of shape, permanent magnets are divided into two main categories: cubic and cylindrical. In the past researches, cylindrical overhead magnets have been used to perform MAF on free surfaces, which is not very efficient due to the time-consuming process. In this research, first of all, the methods of making overhead magnets have been examined to find the optimal magnetic conditions. Then, in order to increase the efficiency of the process, methods to increase the efficiency of the overhead magnet have been investigated. Based on this, the mentioned methods have been discussed and evaluated. According to the results, in the method of using a ball magnet and connecting it to a cylindrical magnet, the magnetism density is significant, and also by grooving the head magnet, the roughness changes on the inclined surfaces of the ferromagnetic workpiece from 21% to It reached 34.4% and in the inclined area with a curvature angle of 90 and 105 degrees of the surface of the ferromagnetic workpiece, a 9% increase in roughness changes occurs.

Optimizing energy consumption in industrial robots can reduce operating costs, improve performance, and extend the life of the robot during manufacturing. In recent years, with the progress of science and technology, new technologies such as cloud computing, big data, etc. have continuously emerged, and in particular, cloud computing technology has been used in robot research that improves the real-time performance of the designed robot. It can also provide high energy efficiency, low cost, etc. One of the most important aspects of this technology is its use in continuous monitoring of robots' performance, which can guarantee its optimal performance. In this research, first, an overview of the methods of reducing energy consumption is presented, and then the effectiveness of using edge computing technology in reducing energy is analyzed. For this purpose, the use of algorithms to optimize the performance of the robot, including its trajectory and working times, is controlled by the edge. The results of the simulations show that the energy consumption can be significantly reduced by using edge technology.