Electrical Discharge Machining (EDM) is a widespread Nontraditional Machining (NTM) processes for manufacturing of a complicated geometry or very hard metals parts that are difficult to machine by traditional machining operations. Electrical discharge machining is a material removal (MR) process characterized by using electrical discharge erosion. This paper discusses the optimal parameters of EDM on high-speed steel (HSS) AISI M2 as a workpiece using copper and brass as an electrode. The input parameters used for experimental work are current (10, 24 and 42 A), pulse on time (100, 150 and 200 µs), and pulse off time (4, 12 and 25 µs) that have effect on the material removal rate (MRR), electrode wear rate (EWR) and wear ratio (WR). A Minitab software environment was used to adopt Taguchi method to analyze the effect of input on output parameters of EDM. The results of the present work showed that the best of MRR in copper and brass electrodes with (current 42 A, pulse on time 100 µs and pulse off time 25 µs) are (84.355×10-3 g/min) and (43.243×10-3 g/min) respectively, and the MRR predicted by Taguchi are (86.1751×10-3 g/min) in copper electrode by using the parameters with (current 10 A, pulse on time 200 µs and pulse off time 25 µs) and (43.2979×10-3 g/min) in brass electrode at current 42 A, pulse on time 100 µs, and pulse off time 25 µs. The lowest EWR occurs with a value of (1.4510×10-3 g/min) with (current 10 A, pulse on time 100 µs, pulse off time 4 µs) variables when using a copper electrode. The highest WR (2.602508) was found for the brass electrode with (current 24 A, pulse on time 200 µs, pulse off time 4 µs) variables.
In this work, we construct projectively distinct (k,3)-arcs in the projective plane PG(2,9) by applying a geometrical method. The cubic curves have been been constructed by using the general equation of the cubic. We found that there are complete (13,3)-arcs, complete (15,3)-arcs and we found that the only (16,3)-arcs lead to maximum completeness
The temperature distributions are to be evaluated for the furnace of Al-Mussaib power plant. Monte Carlo simulation procedure is used to evaluate the radiation heat transfer inside the furnace, where the radiative transfer is the most important process occurring there. Weighted sum of gray-gases model is used to evaluate the radiative properties of the non gray gas in the enclosure. The energy balance equations are applied for each gas, and surface zones, and by solving these equations, both the temperature, and the heat flux are found.
Good degree of accuracy has been obtained, when comparing the results obtained by the simulation with the data of the designing company, and the data obtained by the zonal method. In
... Show MoreIn this paper, a new technique is offered for solving three types of linear integral equations of the 2nd kind including Volterra-Fredholm integral equations (LVFIE) (as a general case), Volterra integral equations (LVIE) and Fredholm integral equations (LFIE) (as special cases). The new technique depends on approximating the solution to a polynomial of degree and therefore reducing the problem to a linear programming problem(LPP), which will be solved to find the approximate solution of LVFIE. Moreover, quadrature methods including trapezoidal rule (TR), Simpson 1/3 rule (SR), Boole rule (BR), and Romberg integration formula (RI) are used to approximate the integrals that exist in LVFIE. Also, a comparison between those methods i
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Hartree-Fock calculations for even-even Tin isotopes using
Skyrme density dependent effective nucleon-nucleon interaction are
discussed systematically. Skyrme interaction and the general formula
for the mean energy of a spherical nucleus are described. The charge
and matter densities with their corresponding rms radii and the
nuclear skin for Sn isotopes are studied and compared with the
experimental data. The potential energy curves obtained with
inclusion of the pairing force between the like nucleons in Hartree-
Fock-Bogoliubov approach are also discussed.
Purpose: the purpose of this study is to investigate how managers working for the General Authority for Irrigation and Reclamation Projects react to the impact of Emotional Intelligence (EI) on their performance. Theoretical framework: The current study includes an intellectual framework on two variables, namely EI and Manager Performance (MP), because it is essential to investigate the relationship between these two variables and the impact of EI on MP. Design/methodology/approach: The research problem is that a manager's capacity to make wise decisions about their work or interactions with subordinates is diminished when they have inadequate EI. The questionnaire is used as a tool for gathering data for the study, and the st
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The research aimed to diagnose and interpretation of impact nature between Communities of practice dimensions (participation and spreading knowledge, confidence, social capital build) deportation strategic change choices (reengineering business process, business re-structuring, business innovation) in construction companies in the Iraqi Ministry of Construction and Housing, the research tested 4 construction companies working in investing sector in Iraq, the research applied on a sample of 102 persons who participated in Communities of practice distributed in several administrative levels (directors, division directors, project directors and engineers) the research used questionnaire as a main tool for dat
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In this paper, a theoretical analysis of optimum bed thickness operates under mass transfer control for realizing a high efficiency and reaction conversion of an electrochemical reactor has been made based on flowthrough porous electrode (FTPE) configuration. Many models have been used to represent the optimum bed thickness by taking a look into previous works concerned and collecting all related information, data, and models. The parameters that affect the optimum bed thickness have been visualized and reviewed, and almost all of them have been examined by experimental data from different sources and based on the various models. It has been found that the increase in electrolyte flow rate, concentration, limiting current density, and sp
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The behavior of AC conductivity (σac), loss tangent (tan δ), and relative permittivity (ε′) for composites of PVC-P/graphite electrode waste (GEW) was investigated, and a qualitative explanation was provided as a function of PVC-P weight fractions (0, 5, 10, 15, 20, and 25) wt. percent, temperature (30-90) °C, and frequency (100Hz-2MHz). The behaviors of the composites' ac. conductivity and impedance as a frequency function and temperature have been examined. The permittivity was shown to rise with increasing temperature (Tg). The relative permittivity increased as the GEW filler concentration increased and was highest in the low-frequency range; nevertheless decreased as the frequency increased.
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A comparative study was done on the adsorption of methyl orange dye (MO) using non-activated and activated corn leaves with hydrochloric acid as an adsorbent material. Scanning electron microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR) were utilized to specify the properties of adsorbent material. The effect of several variables (pH, initial dye concentration, temperature, amount of adsorbent and contact time) on the removal efficiency was studied and the results indicated that the adsorption efficiency increases with the increase in the concentration of dye, adsorbent dosage and contact time, while inversely proportional to the increase in pH and temperature for both the treated and untreated corn leav
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