Preferred Language
Articles
/
alkej-405
Effect of optimal shot peening time on fatigue life for aluminum alloy 6061-T651
...Show More Authors

The compressive residual stresses generated by shot peening, is increased in a direct proportional way with shot peening time (SPT). For each metal, there is an optimum shot peening time (O.S.T) which gives the optimum fatigue life. This paper experimentally studied to optimize shot peening time of aluminium alloy 6061-T651 as well as using of and analysis of variance (ANOVA).

Two types of fatigue test specimens’ configuration were used, one without notch (smooth) and the other with a notch radius (1,25mm), each type was shot peened at different time. The (O.S.T) was experimentally estimated  to be 8 minutes reaching the surface stresses at maximum peak of -184.94 MPa.

A response surface methodology (RSM) is presented to optimize the surface properties of fatigue life due to effect of two parameters (shot peening time and fatigue stresses). A statistical software was used to perform analysis of variance (ANOVA)  to predict the optimum shot peening time. The results were 8.007 minutes without notch and 7.53 minutes with notch. Two 2nd degree polynomials were obtained for the two studied cases with confidence level of 95%. Experimentally26.67% enhancement in fatigue life was obtained, but after using (RSM), the results gave 61% improvement, compared with ref. [2].

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Experimental Study on the Effect of Using Metallic Brushes on the Charging and Discharging Time of Thermal Energy Storage Unit
...Show More Authors

Phase change materials are known to be good in use in latent heat thermal energy storage (LHTES) systems, but one of their drawbacks is the slow melting and solidification processes. So that, in this work, enhancing heat transfer of phase change material is studied experimentally for in charging and discharging processes by the addition of high thermal conductive material such as copper in the form of brushes, which were added in both PCM and air sides. The additions of brushes have been carried out with different void fractions (97%, 94% and 90%) and the effect of four different air velocities was tested. The results indicate that the minimum brush void fraction gave the maximum heat transfer in PCM and reduced the time

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Proceeding Of The 1st International Conference On Advanced Research In Pure And Applied Science (icarpas2021): Third Annual Conference Of Al-muthanna University/college Of Science
Effect of etching time on the track density of fission fragments human teeth samples with Lexan detector
...Show More Authors

View Publication
Scopus (1)
Scopus Crossref
Publication Date
Sun May 01 2011
Journal Name
Thin Solid Films
Effect of temperature and deposition time on the optical properties of chemically deposited nanostructure PbS thin films
...Show More Authors

View Publication
Scopus (56)
Crossref (48)
Scopus Clarivate Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Influence of the annealing time on the structural properties for Flash evaporated InSb films
...Show More Authors

Indium Antimonide (InSb) thin films were grown onto well cleaned glass substrates at substrate temperatures (473 K) by flash evaporation. X-ray diffraction studies confirm the polycrystalline of the films and the films show preferential orientation along the (111) plane .The particle size increases with the increase of annealing time .The transmission spectra of prepared samples were found to be in the range (400-5000 cm-1 ) from FTIR study . This indicates that the crystallinity is improved in the films deposited at higher annealing time.

View Publication Preview PDF
Crossref
Publication Date
Sun Jun 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Different Thermal Treatments on Corrosion Behavior of the Hydroxyapatite Coated on Ti-6Al-4V Alloy by Electrophoretic Deposition and Dip Coating
...Show More Authors

    In this research, the study of thermal treating by laser, plasma glow discharge and tubular furnace on Ti-6Al-4V alloy coated with hydroxyapatite by methods of dip coating and electrophoretic deposition .A group of samples was coated by dip coating and another group was coated by electrophoretic deposition. The first group was treated by pulse laser 10 (mJ) as energy for samples from both coating with uniform distributed pulses on every single sample surface, The second thermal treating was made by plasma glow discharge in a locally made system with argon atmosphere, 600 Volt , and 6 cm distance between the electrodes, The third treating was made by tubular furnace in air atmosphere and 400 °C for 1 hour duration. T

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Performance Comparison of Different Advanced Control Schemes for Glucose Level Control under Disturbing Meal
...Show More Authors

Abstract

In this work, diabetic glucose concentration level control under disturbing meal has been controlled using two set of advanced controllers. The first set is sliding mode controllers (classical and integral) and the second set is represented by optimal LQR controllers (classical and Min-, ax). Due to their characteristic features of disturbance rejection, both integral sliding mode controller and LQR Minmax controller are dedicated here for comparison. The Bergman minimal mathematical model was used to represent the dynamic behavior of a diabetic patient’s blood glucose concentration to the insulin injection. Simulations based on Matlab/Simulink, were performed to verify the performance of each controll

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study of Fatigue and Bending Properties For Epoxy / Kevlar - Glass Fibers and Hybrid Composite
...Show More Authors

In this research a study of the effect of quality, sequential and directional layers for three types of fibers are:(Kevlar fibers-49 woven roving and E- glass fiber woven roving and random) on the fatigue property using epoxy as matrix. The test specimens were prepared by hand lay-up method the epoxy resin used as a matrix type (Quick mast 105) in prepared material composit . Sinusoidal wave which is formed of variable stress amplitudes at 15 Hz cycles was employed in the fatigue test ( 10 mm )and (15mm) value 0f deflection arrival to numbers of cycle failure limit, by rotary bending method by ( S-N) curves this curves has been determined ( life , limit and fa

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Dec 05 2022
Journal Name
Baghdad Science Journal
Effect of Secondary Metabolite Crude of Metarhizum anisopliea Fungus on the Second Larval Stage of the Housefly Musca domestica
...Show More Authors

         The house flies Musca domestica )Diptera:musidae) are the primary carrier of many pathogens such as cholera, typhoid, anthrax, and others. The use of chemical pesticides as a basic method of control leads to many problems at the environmental and health level. The use of safe alternatives to chemical pesticides has become an urgent necessity. The research aims to find biological alternatives that are environment-friendly and non-pathogenic to humans in controlling house flies through the possibility of extracting and diagnosing some secondary metabolites produced by the fungus Metarhizium anisopliae and testing their effects on the second larval stage of house flies using different treatment methods that include

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Spectral Technique for Baud Time Estimation
...Show More Authors

A new approach for baud time (or baud rate) estimation of a random binary signal is presented. This approach utilizes the spectrum of the signal after nonlinear processing in a way that the estimation error can be reduced by simply increasing the number of the processed samples instead of increasing the sampling rate. The spectrum of the new signal is shown to give an accurate estimate about the baud time when there is no apriory information or any restricting preassumptions. The performance of the estimator for random binary square waves perturbed by white Gaussian noise and ISI is evaluated and compared with that of the conventional estimator of the zero crossing detector.

View Publication Preview PDF
Crossref
Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
Wavelet Analysis For Sunspot Time Series
...Show More Authors

Abstract

In this research we study the wavelet characteristics for the important time series known as Sunspot, on the aim of verifying the periodogram that other researchers had reached by the spectral transform, and noticing the variation in the period length on one side and the shifting on another.

A continuous wavelet analysis is done for this series and the periodogram in it is marked primarily. for more accuracy, the series is partitioned to its the approximate and the details components to five levels, filtering these components by using fixed threshold on one time and independent threshold on another, finding the noise series which represents the difference between

... Show More
View Publication Preview PDF
Crossref