Showing 12 results for Material Removal Rate
Behzad Jabbaripour, M Sadeghi, , ,
Volume 11, Issue 2 (9-2011)
Abstract
Due to outstanding properties of γ–TiAl intermetallic such as high resistance against fatigue, oxidation, corrosion, creep, dynamic vibration, high working temperature and also its application in aerospace and automotive industry, turbojet engines and blade manufacturing; in this paper, electrical discharge machining (EDM) of γ–TiAl intermetallic by means of three kinds of tool electrodes including copper, graphite and aluminum is investigated, to compare the output characteristics of the machining process such as material removal rate, tool wear ratio, surface roughness and topography and EDS elemental analysis of machined surfaces. The results indicate that major elements in chemical composition of γ–TiAl machined surfaces are including titanium, aluminum, carbon and oxygen. The variation of tool material has not significant effect on formation of different chemical compounds and phases or in other words surface modification of machined surface. While it mainly affects other aspects of output characteristics such as material removal rate, tool wear ratio and surface roughness.
Behzad Jabbaripour, , , ,
Volume 12, Issue 5 (1-2013)
Abstract
γ–TiAl intermetallic has outstanding properties such as high resistance against fatigue, oxidation, corrosion, creep, dynamic vibration and high working temperature. These intermetallics are applied in aerospace and automotive industry, turbojet engines and blade manufacturing. In this paper, powder mixed electrical discharge machining (PMEDM) of γ–TiAl intermetallic by means of different kinds of powders including Al, SiC, Gr, Cr and Fe is investigated to compare the output characteristics of the process such as surface roughness, tool wear rate, material removal rate and surface topography with each other. This is an experimental investigation, by means of die sinking EDM machine and a special tank for machining. The results indicate that, aluminum powder as the most appropriate kind of powder in the optimum particle concentration of 2 g/l, improves the surface roughness about 32% comparing with conventional EDM, decreases the tool wear rate about 19%, but decreases the material removal rate about 7.5% and also the Al powder leads to improving the machined surface topography and decreasing the surface defects and micro cracks.
, Behnam Khosrozadeh, Babak Sadizadeh, Hamed Kakoulvand,
Volume 13, Issue 12 (2-2014)
Abstract
In this study the interaction of material and ultrasonic vibration of workpiece at different pulse on times (Ti) and discharge currents (I) in the electrical discharge machining (EDM) has been studied. The materials of machined samples were AISI H13 tool steel and FW4 weld steel. The results show that ultrasonic vibration of workpiece, independent of workpiece material increase material removal rate (MRR) and reduce tool wear ratio (TWR) and surface roughness. Also the results indicate that the effect of ultrasonic vibration on the material removal rate increase of FW4weld steel is higher than AISI H13 tool steel, and the reduction of tool wear ratio of FW4 weld steel is more than AISI H13 tool steel.
Ahad Gholipoor, Hamid Baseri, Mohsen Shakeri,
Volume 14, Issue 1 (4-2014)
Abstract
The near dry EDM process uses a mixture of a liquid and a gas as dielectric medium. In this study, near dry EDM process at three levels of discharge energy and with two brass and copper electrode was studied to investigate the effects of tool material on machining performance. Also, the Taguchi method of design of experiments technique was employed to study the effects of nonelectrical parameters such as tool rotational speed, liquid flow rate, gas pressure and also discharge energy on material removal rate (MRR), electrode wear ratio (TWR) and surface roughness (SR) and also the analysis of variance (ANOVA) was employed to find the most important factors effecting MRR, TWR and SR. The results showed that copper electrode has higher MRR and lower TWR as compared to brass electrode. Also the analysis of main effect plots obtained by Taguchi method indicated that MRR and SR is enhanced by increasing water flow rate and discharge energy and also increasing gas pressure leads to lower TWR. The ANOVA results showed that discharge energy is the most important factor influencing MRR, TWR and SR.
Ali Ghoddosian, Masoud Pour, Mojtaba Sheikhi Azghandi,
Volume 14, Issue 2 (5-2014)
Abstract
In this research, the effects of cutting parameters on material removal rate and surface roughness, are investigated. Therefore, after that the comprehensive model of low-immersion milling is developed, the optimum cutting conditions has to be found for optimizing all of them. The stability criterion is considered as the optimization constraint which is calculated by TFEA. On the other hand, instead of using explicit equation for calculating surface roughness, such as previous works, surface roughness is calculated by TFEA for all of the cases that are needed. Finally, the ability of Genetic algorithm, Particle Swarm Optimization and Imperialist Competitive Algorithm for searching optimum cutting parameters are compared and the results are reported. By comparing the results of the three algorithms it is shown that the ICA is more powerful to deal with nonlinearity aspects of the problem and to tackle sticking in local minimums. Also it is demonstrated that the convergence rate of the ICA is faster than the other two methods. Finally, experiments to confirm the changes of the objective function toward optimal point are done and error percentage of objective function at obtained optimal point compared with experimental result is determined.
Mohammad Reza Shabgard, Reza Rostami Heshmatabad,
Volume 16, Issue 3 (5-2016)
Abstract
Electrolyte type, due to the nature of its constituent ions, affects the reaction rate, the uniformity of the electric field and formation of the external layer on the workpiece surface in the machining area during the electrochemical machining process, as well as it causes to create different dissolution behaviors of the workpiece. Therefore in this study the effect of sodium chloride, sodium nitrate, potassium chloride and hydrochloric acid electrolytes with different currents on the electrochemical machining characteristics of stainless steel 304, including material removal rate, side gap and surface roughness, has been investigated. The results showed that the formation of passive layer during the machining with sodium nitrate electrolyte reduces the material removal rate and side gap compared with sodium chloride and potassium chloride electrolytes. According to the experimental results the surface roughness in the sodium chloride and potassium chloride electrolytes is decreased by increasing the machining current, but increases in the sodium nitrate electrolyte. Also the material removal rate slight increase and side gap increase at sodium chloride, sodium nitrate and potassium chloride when combined with hydrochloric acid. On the other hand, the surface roughness reduces in the combined sodium chloride and potassium chloride electrolytes, but increases in the combined sodium nitrate electrolyte.
Mohammad Shafiei Alavijeh, Hossein Amirabadi,
Volume 17, Issue 8 (10-2017)
Abstract
The most essential problem in lapping process is low material removal rate which leads to increase in production costs and time. Thus, in this process, it's essential to select a condition that besides producing pieces with required flatness and roughness, has a high material removal rate. In this research, effects of parameters such as abrasive particle size, abrasive particles concentration in slurry, and lapping pressure on material removal rate, flatness and surface roughness were studied by experimental method in single sided lapping of flat workpieces made of 440c steel. In the following, effect of aforementioned parameters on material removal rate, flatness and surface roughness of lapped surface has been modeled using artificial neural network. Finally, by exerting multi-objective particle swarm optimization, simultaneous optimization of material removal rate, surface roughness and flatness of lapping pieces has been conducted and related Pareto front has been obtained. Obtained results show that by using Multi-objective particle swarm optimization algorithm we can produce workpieces with required surface roughness and flatness with high material removal rate. Consequently, by using this method moreover producing workpieces with desired quality, production cost and time would decrease.
Mohammadreza Shabgard, Ahad Gholipoor,
Volume 17, Issue 12 (2-2018)
Abstract
Electric discharge machining is one of the most widely used non-traditional machining techniques which use thermal energy for machining in small dimensions, machining complex shapes and machining hard materials with high strength such as ceramics and heat-treated steels. In this study the ultrasonic vibrations and magnetic field assisted EDM process as a new hybrid process was introduced and used for machining of AISI H13 too steel, to solve the EDM process limitations such as low material removal rate. In this investigation, several experiments were designed and performed based on full factorial method by selecting pulse current and pulse duration as most effective parameters of EDM process in order to study the effects of applying ultrasonic vibrations to tool electrode and external magnetic field around gap distance of EDM process, simultaneously, on material removal rate and tool wear rate. According the results, applying ultrasonic vibrations to tool electrode and external magnetic field around gap distance of EDM process, simultaneously, despite the increases of tool wear rate, increases the material removal rate as compared with EDM (60%), ultrasonic vibrations assisted EDM (40%) and magnetic field assisted EDM processes (55%) in all pulse durations and pulse currents except in pulse current of 32 A. In pulse current of 32 A, because of the interference of the influences of applying ultrasonic vibrations to tool electrode and external magnetic field around gap distance, the material removal rate and tool wear ratio are decreased.
S. Dinarvand, B. Jabbaripour,
Volume 20, Issue 7 (6-2020)
Abstract
Modern intermetallic compound of gamma titanium aluminide (γ-TiAl) due to its low density, high elastic modulus, high resistance to oxidation, corrosion, and ignition has recently been considered in the aerospace and automotive industries. Traditional machining of this alloy is so difficult. In the current study, electrical discharge machining of γ-TiAl samples is investigated using different tool electrodes of graphite, copper, and aluminum. The results show that when using aluminum electrodes, tool wear rate is averagely 3.2 times more than copper and 5.8 times more than graphite tools. In addition, when using graphite electrodes, the average material removal rate is 4.2 times more than copper and 7.7 times more than aluminum. Machining by aluminum tool leads to formation of Al2O3 and TiO2 oxide compounds on the work surface but in machining by graphite electrode, TiC and Ti8C5 carbide phases are created on the work surface. In machining by graphite due to formation of hard carbide compounds in the recast layer, the microhardness is higher than the machined sample by the aluminum tool, where oxide compounds exist on the surface and the hardness of recast layer in the machined sample by copper electrode is less than the other two electrodes, because of existing phases such as copper oxide with less hardness. The highest electrochemical corrosion resistance belongs to the machined specimen using graphite tool and the lowest corrosion resistance is related to the machined sample by aluminum electrode. Reducing oxide and aluminum compounds and increasing carbide phases enhance the corrosion resistance of γ-TiAl machined samples.
Vahid Tahmasbi, Mohammad Hafez Baghi, Sepehr Aeinehbandy, Amin Sousanabadi Farahani,
Volume 23, Issue 7 (7-2023)
Abstract
Today, various military, aerospace, automotive, etc. industries need materials with a high strength-to-weight ratio. The use of metal-based composite materials, especially aluminum-based composites, has increased greatly. Machining is needed to achieve high dimensional accuracy in products made with aluminum-based composites. Due to the presence of reinforcing material such as silicon carbide, machining of this type of material is difficult. Therefore, it is important to study the parameters affecting the machining of aluminum-based composites. In this study, the effect of spindle speed, feed rate, depth of cut and percentage of reinforcing particles were discussed using experimental and statistical test methods. The responses of surface roughness and material removal rate were investigated. The behavior of the input parameters on the responses of the process has been carefully investigated quantitatively and qualitatively. Answers have also been optimized. According to the obtained results, the spindle speed has the greatest effect on the surface roughness. Also, feed rate 33%, spindle speed 28%, depth of cut 26% and the percentage of reinforcing particles 13% have an effect on the chipping rate.
Moein Taheri , Fereshteh Ghane ,
Volume 23, Issue 10 (10-2023)
Abstract
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.
Zeinab Mandizadeh , Fatemeh Ramezani , Mohammad Khalili ,
Volume 23, Issue 10 (10-2023)
Abstract
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.
