Al-Khwarizmi Engineering Journal,
Vol. 11, No. 3 (2015)
Marwa K. Qate’a
Ali H. kadhum
Faiz F. Mustafa
The Influence of the Magnetic Abrasive Finishing System for Cylindrical Surfaces on the Surface Roughness and MRR.
Magnetic abrasive finishing (MAF) is one of the advanced finishing processes, which produces a high level of surface quality and is primarily controlled by a magnetic field. This paper study the effect of the magnetic abrasive finishing system on the material removal rate (MRR) and surface roughness (Ra) in terms of magnetic abrasive finishing system for eight of input parameters, and three levels according to Taguchi array (L27) and using the regression model to analysis the output (results). These parameters are the (Poles geometry angle, Gap between the two magnetic poles, Grain size powder, Doze of the ferromagnetic abrasive powder, DC current, Workpiece velocity, Magnetic poles velocity, and Finishing time). This work includes the classification of the MAF system, implementation of MAF machine and magnetic poles, preparing ferromagnetic abrasive powder by mix the iron oxide with industrial diamond powder and studying the effects of magnetic abrasive finishing on the MRR and surface roughness. MINITAB software was used to estimate the influence of the Magnetic Abrasive Finishing (MAF) parameters on the MRR and Surface Roughness for a cylindrical duralumin (2024) workpiece. The results show that the poles geometry angle has the biggest influence on MRR (30.18%) followed by Finishing time, Gap, Magnetic poles velocity, Workpiece velocity, Current, Doze, and Grain size powder, respectively. Also the results show that the workpiece velocity has the biggest influence on the surface roughness (23.80%) followed by Doze, Gap, Current, poles geometry angle, Magnetic poles velocity, Grain size powder, and Finishing time, respectively. Regression results show that the decreasing of poles geometry angle from 30°to -30° leads to increasing MRR. While the decreasing of the workpiece velocity from (679 rpm) to (567 rpm) leads to increase the Roughness.
Rafal M. Khalil
Somer M. Nacy
Deflection Analysis of an Elastic Single Link Robotic Manipulator.
Robotics manipulators with structural flexibility provide an attractive alternative to rigid robotics manipulators for many of the new and evolving applications in robotics. In certain applications their use is unavoidable. The increased complexity in modeling and control of such manipulators is offset by desirable performance enhancements in some respects. In this paperthe single- link flexible robotics manipulator was designed and implemented from Perspex and designed with 0.5 m length , 0.02 m width and with 0.004 m thickness with mass located at the tip. There are four subsystems; motion, control, accelerometer and gyro and a host computer subsystem. The work principle of single-link robotics manipulator is the base servomotor. It rotates a hub with the link on it and measure the tip deflection. the deflection was measured for three cases without load, with 27.5 and with 59.4 gram at the end of the flexible link . During each of the above cases I rotated the base servo motor at an angular velocity equals to 90 deg./s using control card based on ATMEGA640 microcontroller. the deflection was measured for the three cases and the deflection measured by MMA7631 Accelerometer and Gyro . This accelerometer controlled by using MEGA Arduino board . Then the dataI collected collected from accelerometer and plot it using MATLAB software and compared between theoretical results obtained from MATLAB program that based on Lagrange equation of motion and experimental results and we found the maximum deflection occurred when V=180 deg/sec and tip load=59.5 gram.
Ahmed N. Al-Khazraji
Samir A. Amin
Saad M. Ali
This paper concerned with study the effect of a graphite micro powder mixed in the kerosene dielectric fluid during powder mixing electric discharge machining (PMEDM) of high carbon high chromium AISI D2 steel. The type of electrode (copper and graphite), the pulse current and the pulse-on time and mixing powder in kerosene dielectric fluid are taken as the process main input parameters. The material removal rate MRR, the tool wear ratio TWR and the work piece surface roughness (SR) are taken as output parameters to measure the process performance. The experiments are planned using response surface methodology (RSM) design procedure. Empirical models are developed for MRR, TWR and SR, using the analysis of variance (ANOVA).The best results for the productivity of the process (MRR) obtained when using the graphite electrodes, the pulse current (22 A), the pulse on duration (120 µs) and using the graphite powder mixing in kerosene dielectric reaches (82.84mm³/min). The result gives an improvement in material removal rate of (274%) with respect to the corresponding value obtained when copper electrodes with kerosene dielectric alone. The best results for the tool wear ratio (TWR) of the process obtained when using the copper electrodes, the pulse current (8 A), the pulse on duration (120 µs) and using the kerosene dielectric alone reaches (0.31 %). The use of graphite electrodes, the kerosene dielectric with 5g/l graphite powder mixing, the pulse current (8 A), the pulse on duration (40 µs) give the best surface roughness of a value (2.77 µm).This result yields an improvement in SR by (141%) with respect to the corresponding value obtained when using copper electrodes and the kerosene dielectric alone with the same other parameters and machining conditions.
Jafar M. Hassan
Qussai J. Abdul-Ghafour
Mohammed F. Mohammed
Influences of the Twisted Strips Insertion on the Performance of Flat Plate Water Solar Collector.
Awham M. Hameed
Entihaa G. Daway
Muaed F. Abd- Al Majed
Morphology and Mechanical Properties of (Epoxy/PVC) Blend.
Alalkawi H. J. M
Basim A. Sadkhan
Noor N. Abed
Black paint laser peening (bPLP) technique is currently applied for many engineering materials , especially for aluminum alloys due to high improvement in fatigue life and strength . Constant and variable bending fatigue tests have been performed at RT and stress ratio R= -1 . The results of the present work observed that the significance of the surface work hardening which generated high negative residual stresses in bPLP specimens .The fatigue life improvement factor (FLIF) for bPLP constant fatigue behavior was from 2.543 to 3.3 compared to untreated fatigue and the increase in fatigue strength at 107 cycle was 21% . The bPLP cumulative fatigue life behavior was improved by 1.786 at L-H and 1.55 at H-L due to black paint coating .
Wavelength Division Multiplexing Passive Optical Network modeling Using Optical System Simulator.
Shibly Ahmed AL-Samarraie
Alaq Sabah Badri
Mustafa H. Mishary
Integral Sliding Mode Control Design for Electronic Throttle Valve System.
One of the major components in an automobile engine is the throttle valve part. It is used to keep up with emissions and fuel efficiency low. Design a control system to the throttle valve is newly common requirement trend in automotive technology. The non-smoothness nonlinearity in throttle valve model are due to the friction model and the nonlinear spring, the uncertainty in system parameters and non-satisfying the matching condition are the main obstacles when designing a throttle plate controller In this work, the theory of the Integral Sliding Mode Control (ISMC) is utilized to design a robust controller for the Electronic Throttle Valve (ETV) system. From the first instant, the electronic throttle valve dynamics is represented by the nominal system model, this model is not affected by system parameters uncertainty and the non-smooth nonlinearities. This is a consequence of applying the integral sliding mode control. The ISMC consists of two part; the first is the nominal control which is used to control the nominal system, while the second is a discontinuous part which is used to eliminate the effects of the parameters uncertainty and the non-smooth nonlinearities from system model. These features for the ISMC are proved mathematically and demonstrated numerically via seven numerical simulations and for different desired trajectories. The simulation results clarify that for different system parameters, the ETV behaves as a nominal system. This enables to freely and precisely select the system response characteristics and the time required for the throttle angle to reach the desired value. Moreover the ability to deal with the chattering problem is demonstrated through the worked simulation tests, where the chattering is eliminated via approximating the signum function by arc tan function.
Multi-Focus Image Fusion Based on Pixel Significance Using Counterlet Transform.
Tensile and Compressive Properties of Kaolin Rienforced Epoxy.
The toughening of epoxy resins with the addition of organic or inorganic compounds is of great interest nowadays, considering their large scale of applications. In the present work, composites of epoxy are synthesized with kaolin particles having different particle sizes as reinforcement. Composites of epoxy with varying concentration (0 to 40 weight %) of kaolin was prepared by using hand lay method. The variation of mechanical properties such as modulus of elasticity, yield, tensile, and compressive strength with filler content was evaluated. The composite showed improved modulus of elasticity and compressive properties on addition of filler. In contrast, the tensile and yield strength of the composites decreases with rising kaolin content. It is also observed that mechanical properties increase with decrease in particle size in all cases.