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Article
Studying the Effect of Mixture of Pomegranate Peel and Licorice on the Mechanical Properties of Epoxy

Author: Najmuldeen Yousif Mahmood
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2017 Volume: 20 Issue: 4 Pages: 871-875
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Reinforcement process of epoxy has been widely used to improvement of mechanical properties. Therefore, this work is concerned with the reinforcement of epoxy by adding natural materials (Pomegranate peel and Licorice particles) at epoxy. Different percentages of particles (5, 10, 15 and 20%) were used. The mechanical testing were included tensile, bending, hardness and impact tests. Hardness of epoxy was increased at increasing of Pomegranate peel (PP) and Licorice (L) percentages. Impact resistance of epoxy with Pomegranate peel (PP) has reached the highest at (10%), while with Licorice (L) has reached the highest at (5%). The results of tensile strength represent that increases of tensile strength at all percentages of (L), while (PP) showed that decreases at (5%) and increases at others percentage. Bending strength of epoxy has increased as increasing of (PP) at all percentage that used, but it has increased at (5, 10 and 20%) of (L), while it has dropped at (15%).

استخدمت عملية تقوية الايبوكسي على نطاق واسع لتحسين الخواص الميكانيكية. لذلك تعلقت الدراسة بتقوية الايبوكسي بأضافة المواد المواد الطبيعية (دقائق قشور الرمان وعرق السوس) الى الايبوكسي. استخدمت نسب مختلفة من الدقائق (5, 10, 15 و 20%). الاختبارات الميكانيكية تظمنت اختبارات الشد , الانحناء , الصلادة و الصدمة. تزداد صلادة الايبوكسي بزيادة نسبة قشور الرمان وعرق السوس. وصلت مقاومة الصدمة للايبوكسي اقصى قيمة عند (10%) من قشور الرمان بينما وصلت القيمة القصوى لمقاومة الصدمة عند (5%) من عرق السوس. بينت نتنائج مقاومة الشد زيادة عند كل نسب عرق السوس بينما تتناقص عند (5%) وازدات عند باقي النسب من قشور الرمان. مقاومة الانحناء للايبوكسي تزداد بزيادة قشور الرمان عند كل النسب في حين تزداد مقاومة الانحناء عند (5 , 10 و 20%) من عرق السوس وتنخفض عند (15%).


Article
STUDY THE MICROWAVE ENERGY EFFECTS ON MECHANICAL PROPERTIES AND ESTIMATED FATIGUE LIFE OF AA7075-T6

Authors: Ahmed Adnan AL-Qaisy --- Najmuldeen Yousif Mahmood --- Rasha Mohammed Hussein
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 6 Pages: 114-124
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This study is concerned with the effect of microwave heat treatment of AA7075-T6 on the mechanical properties and fatigue life. Specimens were divided into four groups, firstly, specimens were subjected for 60 min. of microwave heat as a dry, secondly, specimens were subjected for 30 min. of microwave heat as a dry, thirdly, specimens were subjected for 60 min. of microwave heat as a wet, and fourthly, specimens were subjected for 30 min. of microwave heat as a wet condition. Then, it is compared with original alloy (AA7075-T6). The mechanical tests that used in this research are tensile, hardness, surface roughness and fatigue. It is found that hardness of dry specimens is higher than wet specimens, and hardness of dry condition for 60 min. has higher enhancement (15%) as compared with original alloy. Hardness is increased with increasing of time inside the microwave. However, tensile strength of wet conditions has higher than dry conditions; also, tensile strength is increased with decreasing of time inside microwave furnace. Ultimate and yield strength of wet condition for 30 min. have 55% and 99% respectively, enhancement as compared with AA7075-T6. Surface roughness parameter (Ra) of dry conditions has higher than wet conditions and the decreases as decreasing of time inside microwave furnace. Fatigue strength results showed that decreasing as compared with original alloy.


Article
An Experimental Approach and Constructing a New Non-Linear Regression Model for Prediction the Anisotropy Parameters of Annealing Treated Commercially Pure Aluminum Sheets

Authors: Jabbar H. Mohmmed --- Ali A. Mohsen --- Bassam A. Ahmed --- Najmuldeen Yousif Mahmood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 14 Part (A) Engineering Pages: 2775-2783
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Earing is a common phenomenon in deep drawing process that increases the waste of metal. This phenomena is affected by material anisotropy, thus, it is important to study the effects of material parameters on this material behavior. This paper focuses on identify the optimal condition of annealing treatment which result in higher value of normal anisotropy and lower value of planar anisotropy which lead to reduce the waste material in subsequent forming processes. Therefore, in this study, anisotropic behavior and formability of commercially pure aluminum thin sheets was investigated after annealing the samples at different temperatures (350, 400, and 450) °C. Uniaxial tensile tests were carried out at room temperature (25°C) to evaluate formability parameters. For this purpose different tensile test samples in the directions of 0°, 45° and 90° in respect to the rolling direction were prepared. In addition to, metallographic test was carried out to as-received and annealed samples to observe the changes in microstructure. Plastic strain ratio and planar anisotropy of samples were calculated from the tensile test data. Based on the tensile test results of samples, the earing phenomenon due to planar anisotropy in commercially pure aluminum sheet was analyzed. The results indicate that the annealing at 400°C brought the optimum conditions.Moreover, new regressions model for prediction the anisotropy parameters of sheet metal using statistical techniques (SPSS software) were constructed in this work. The experimental data were compared to those predicting values. A comparison clearly indicates that there are good identification between measured and predicted values with multiple correlation coefficients R of 0.932 and accuracy of about 87 %. The results reveal that the proposed model is effective and reliable tool to obtain accurate prediction of the anisotropy behavior of metal sheets.


Article
Evaluation the Mechanical Properties of Shot Peened TIG Welded Aluminum Sheets
تقييم الخواص الميكانيكية لصفائح الالمنيوم الملحومة بطريقة قطب التنكستن المحمي بالغاز الخامل والمعاملة بطريقة القذف بالكرات

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Abstract

A tungsten inert gas (TIG) welding is one of the most popular kinds of welding used to join metals mainly for aluminum alloys. However, many challenges may be met with this kind of joining process; these challenges arise from decay of mechanical properties of welded materials. In the present study, an attempt was made to enhancing the mechanical properties of TIG weld joint of 6061-T6 aluminum alloy by hardening the surfaces using shoot peening technique. To optimize the shoot peening process three times of exposure (5, 10, and 15) min. was used. All peened and unpeened, and welded and unwelded samples were characterized by metallographic test to indicate the phase transformation and modification in microstructure occurring during welding process. Tensile test and Vickers micro-hardness measurements were performed for all samples to investigate the effect of shoot peening on mechanical properties of welded aluminum. The results indicated a significant improvement in properties for peened welded and unwelded samples compared with those unpeened one. Also, the results showed that the tensile and micro-hardness properties were increased with increasing the time of exposure to 15 min. due to generation of compressive residual stresses at surface.

تعتبر عملية اللحام بقطب التنكستن المحمي بالغاز الخامل (TIG) من اكثر انواع اللحام انتشارا والمستخدمة لربط المعادن وخصوصا سبائك الالمنيوم. رغم هذا فهناك العديد من التحديات والتي ممكن مواجهتها عند استخدام هذا النوع من عمليات الربط. هذه التحديات ناشئة من انخفاض الخواص الميكانيكية للمواد الملحومة. في الدراسة الحالية تم عمل محاولة لتحسين الخواص الميكانيكية لوصلة من سبائك الالمنيوم (6061-T6) ملحومة بطريقة اللحام بقطب التنكستن المحمي بالغاز الخامل (TIG) من خلال تصليد السطح باستخدام تقنية القذف بالكرات. وللوصول الى الاسلوب الامثل في عملية القذف بالكرات تم استخدام ثلاث ازمان للتعرض (5,10,15) دقيقة. تم توصيف جميع العينات المعاملة بالقذف بالكرات وغير المعاملة، الملحومة وغير الملحومة من خلال فحص سطح المعدن لبيان التحولات الطورية والتغيرات الحاصلة خلال عملية اللحام. تم اجراء فحص الشد وقياس صلادة فيكرز المجهرية لجميع العينات لدراسة تاثير القذف بالكرات على الخواص الميكانيكية لملحومات الالمنيوم. بينت النتائج تحسن ملموس في خواص العينات المعاملة بالقذف بالكرات الملحومة وغير الملحومة مقارنة بالعينات الغير معاملة. بينت النتائج ايضا ان خواص الشد والصلادة المجهرية قد ازدادت مع زيادة زمن التعرض الى 15 دقيقة نتيجة لتوليد مستويات اعلى من اجهادات الضغط المتبيقية عند السطح.


Article
Study the Effects of Microwave Furnace Heat on The Mechanical Properties and Estimated Fatigue life of AA2024-T3
دراسة تأثير الحرارة الناجمة عن أفران المايكروويف على الخواص الميكانيكية وعمر الكلال لسبيكة الألومنيوم 2024-T3

Authors: Ahmed Adnan AL-Qaisy أحمد عدنان عبد الجبار --- Sameh Fareed Hasan سامح فريد حسن --- Najmuldeen Yousif Mahmood نجم الدين يوسف محمود
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2017 Volume: 23 Issue: 10 Pages: 146-156
Publisher: Baghdad University جامعة بغداد

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Abstract

This research aims to study the effect of microwave furnace heat on the mechanical properties and fatigue life of aluminum alloy (AA 2024-T3). Four conditions were used inside microwave furnace (specimens subjected to heat as dry for 30 and 60min. and specimens subjected to heat as wet (water) for 30 and 60 min.), and compared all results with original alloy (AA 2024-T3). Tensile, fatigue, hardness and surface roughness tests were used in this investigation. It is found that hardness of dry conditions is higher than wet conditions and it increases with increasing of time duration inside microwave furnace for dry and wet conditions. Also, tensile strength has the same behavior of hardness, but it increases with decreasing of time. Dry condition for 60 min. shows the higher fatigue strength than other conditions. Surface roughness parameter (Ra) of dry conditions is higher than wet conditions and it decreases with increasing of duration of time.

يهدف هذا البحث لدراسة تأثير حرارة افران المايكرويف على الخواص الميكانيكية وعمر الكلال لسبيكة الالمنيوم (AA2024-T3). تم استخدام ابرع حالات داخل افران المايكرويف (عينات جافة تتعرض الى حرارة لمدة 30 دقيقة و 60 دقيقة و عينات رطبة (الماء) تتعرض الى حرارة لمدة 30 دقيقة و 60 دقيقة). في هذا البحث تم استخدام اختبار الشد , الكلال , الصلادة و خشونة السطح. وجدت ان الاصلادة للحالات الجافة اعلى من الحالات الرطبة وتتناقص الصلادة بزيادة الزمن داخل فرن المايكرويف بالنسبة للحالات الجافة والرطبة. مقاومة الشد لها نفس سلوك الصلادة ايضا ولكن تزداد مقاومة الشد بنقصان الزمن. مقاومة الكلال للحالة الجافة ولمدة 60 دقيقية ظهرت اعلى من باقي الحالات. عامل خشونة السطح للحالة الجافة ولمدة 60 دقيقة اعلى من الحالة الرطبة وتتناقص بزيادة الزمن للحالتين الجافة والرطبة.

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