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Determination of Optimum Welding Parameters for FSW AA2024-T351
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Abstract

Friction stir welding is a relatively new joining process, which involves the joining of metals without fusion or filler materials. In this study, the effect of welding parameters on the mechanical properties of aluminum alloys AA2024-T351 joints produced by FSW was investigated.

Different ranges of welding parameters, as input factors, such as welding speed (6 - 34 mm/min) and rotational speed (725 - 1235 rpm) were used to obtain their influences on the main responses, in terms of elongation, tensile strength, and maximum bending force. Experimental measurements of main responses were taken and analyzed using DESIGN EXPERT 8 experimental design software which was used to develop the response surface methodology (RSM) models. Mathematical model of responses, as functions of used welding conditions, were obtained and analyzed by ANOVA variance to verify the adequacy of these models. The resultant quadratic models showed that as the rotation speed or welding speed increases, the tensile strength and elongation of the joint firstly increase to a maximum value and then decrease more likely due to the occurrence of void defect. Increasing both welding speed and rotational speed leads to increase the maximum bending force firstly to a maximum value and then decreases. However, the welding speed was found more significant than rotational speed. A good agreement was found between the results of these models and optimization with the experimental ones with confidence level of 95%.

Keywords: Friction stir welding, DOE, RSM, Mechanical properties, Modeling and Optimization .

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Publication Date
Sun Feb 05 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
STUDY OF OPTIMUM CONDITIONS FOR REMOVAL OF HEAVY METAL ELEMENTS BY LOCALLY ISOLATED FUNGI Aspergillus niger.: STUDY OF OPTIMUM CONDITIONS FOR REMOVAL OF HEAVY METAL ELEMENTS BY LOCALLY ISOLATED FUNGI Aspergillus niger.
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The best optimum temperature for the isolate was 30○C while the pH for the maximum mineral removal was 6. The best primary mineral removal was 100mg/L, while the maximum removal for all minerals was obtained after 8 hrs, and the maximum removal efficiency was obtained after 24 hrs. The results have proved that the best aeration for maximum removal was obtained at rotation speed of 150 rpm/ minute. Inoculums of 5ml/ 100ml which contained 106 cell/ ml showed maximum removal for the isolate.

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Engineering
Theoretical and Experimental Investigation of Transient Temperature Distribution in Friction Stir Welding of AA 7020-T53
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Finite element modeling of transient temperature distribution is used to understand physical phenomena occurring during the dwell (penetration) phase and moving of welding tool in friction stir welding (FSW) of 5mm plate made of 7020-T53 aluminum alloy at 1400rpm and 40mm/min.
Thermocouples are used in locations near to the pin and under shoulder surface to study the welding tool penetration in the workpiece in advance and retreate sides along welding line in three positions (penetrate (start welding) , mid, pullout (end welding)).
Numerical results of ANSYS 12.0 package are compared to experimental data including axial load measurements at different tool rotational speeds (710rpm.900rpm.1120rpm and 1400rpm) Based on the experiment

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Publication Date
Fri Apr 29 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
The net effect of the nominal protection coefficients in the production of table eggs and poultry meat in Iraq For the period 1990- 2013.: The net effect of the nominal protection coefficients in the production of table eggs and poultry meat in Iraq For the period 1990- 2013.
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The research aims to measure the net nominal protection coefficients for the products table eggs and poultry meat and the extent of its impact on domestic production volume for the period of 1990- 2013 has been the use of mathematical formulas simplified in the calculation of the transaction process with a view to the extent of support and protection offered by the state pricing policy for products Resources Sector Animal in Iraq and reach search Highlights and most important, there are volatile price state policy with regard to eggs and poultry meat, as it ranged net nominal protection coefficients between the larger and less than the right one, which means that values are unstable to support local producers or consumers, and can be The

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Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Optimum diameter for laser beam and effect of temperature rise on the optical bistability hysteresis loops
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 In this research, analytical study for simulating a Fabry-Perot bistable etalon (F-P cavity) filled with a dispersive optimized nonlinear optical material (Kerr type) such as semiconductors Indium Antimonide (InSb). An optimization procedure using reflective (~85%) InSb etalon (~50µm) thick is described. For this etalon with a (50 µm) spot diameter beam, the minimum switching power is (~0.078 mW) and switching time is (~150 ns), leading to a switching energy of (~11.77 pJ) for this device. Also, the main role played by the temperature to change the etalon characteristic from nonlinear to linear dynamics.

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Publication Date
Sun Jun 07 2015
Journal Name
Baghdad Science Journal
Optimum conditions for Inulinase production by Aspergillus niger using solid state fermentation
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Thirty local fungal isolates according to Aspergillus niger were screened for Inulinase production on synthetic solid medium depending on inulin hydrolysis appear as clear zone around fungal colony. Semi-quantitative screening was performed to select the most efficient isolate for inulinase production. the most efficient isolate was AN20. The optimum condition for enzyme production from A. niger isolate was determined by busing a medium composed of sugar cane moisten with corn steep liquor 5;5 (v/w) at initial pH 5.0 for 96 hours at 30 0C . Enzyme productivity was tested for each of the yeast Kluyveromyces marxianus, the fungus A. niger AN20 and for a mixed culture of A. niger and K. marxianus. The productivity of A. niger gave the highest

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Publication Date
Tue Jun 30 2015
Journal Name
Al-khwarizmi Engineering Journal
Laser Peening on Aluminum Alloy 7049 Using Black Paint Surface Coating
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Abstract

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 behav

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Publication Date
Sun Jan 01 2017
Journal Name
Aes-atema International Conference Series - Advances And Trends In Engineering Materials And Their Applications
Behavior of back filler friction spot welded joints of similar AA2024-T3 & AA6061-T6 aluminum alloy sheets
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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Eatimation Availability Function Through Determination The Optimal Imperfect Preventive Maintenance Period By using Simulation
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This paper deals with the modeling of a preventive maintenance strategy applied to a single-unit system subject to random failures.

According to this policy, the system is subjected to imperfect periodic preventive maintenance restoring it to ‘as good as new’ with probability

p and leaving it at state ‘as bad as old’ with probability q. Imperfect repairs are performed following failures occurring between consecutive

preventive maintenance actions, i.e the times between failures follow a decreasing quasi-renewal process with parameter a. Considering the

average durations of the preventive and corrective maintenance actions a

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Publication Date
Thu Jun 01 2023
Journal Name
Baghdad Science Journal
Determination of fungal and parasitic infections caused vaginitis: molecular identification of Candida parapsilosis in Al-Nasiriyah city, Iraq
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The current study aims to determine the prevalence of Trichomonas vaginalis and Candida spp., and also to identify Candida parapsilosis and some virulence genes. It was conducted in Bint Al-Hoda Hospital of Maternity and Children in Thi-Qar province, south of Iraq for the period from the beginning of January to the end of December 2020. Two hundred and fifty samples were collected from the female genital tract for women whose age ranged between 17-50 years. Microscopic, traditional and molecular tests were used in the sample examination. The results recorded 12 (4.8%) samples infected with T. vaginalis parasite, whereas 130 (52%) samples showed Candida yeast distributed as follows: 75 (30 %) <

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Publication Date
Tue Dec 31 2019
Journal Name
Biochemical & Cellular Archives
DETERMINATION OF MYELOPEROXIDASE, HOMOCYSTEINE AND RELATED OTHER PARAMETERS WITH YOUNG SMOKERS OF CIGARETTE AND NARGHILE IN BAGHDAD CITY
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Smoking is the inhalation of smoke tobacco burning that cover with narghile and cigarettes. There are a many problems result smoking such as, deterioration of health in general, undesirable social phenomenon, waste of money and time and stress.This study design to identify the effects of smoking narghile and cigarettes on levels of MPO, HCY and lipidprofil via determination of those parameters in cohort younger of Baghdad city. So to found the correlation coefficient of MPO and those parameters in groups that smoking cigarette and narghiledaily.As well as, to consider the MPO as biomarker to predictor coronary heart diseases. Increased levels of MPO, HCY total cholesterol (TC), triglyceride (TG), very low-density lipoprotein (VLDL) and low-

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