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Article
The Effect of Thermo-Mechanical Treatment on Mechanical Properties & Microstructure for (Cu-Al-Ni )Shape Memory Alloy

Authors: Muna Khethier Abbass --- Munther Mohamed Al-Kubaisy --- Raad Suhail Ahmed Adnan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 13 Part (A) Engineering Pages: 2518-2526
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This paper aims to study the effect of thermo mechanical treatment in different temperatures of (260 ,280& 300) ◦C on the microstructure and mechanical properties of Cu-14wt%Al-4.5wt%Ni shape memory alloy which prepared by casting method in induction furnace under argon atmosphere. Then thermo –mechanical treatment was performed upon the alloy by applying stress of 190MPa with heating upto 260◦C,280◦C,300◦C, then cooled to room temperature performingstrain recovery measurement. Many tests and inspections such as optical and SEM examinations , DSC Measurement ,XRD inspection , compression and Vickers hardness tests were investigated. The results showed that there is an increase in the transformation temperatures, shape memory limits at 300◦C .It was found that hardness increases and Young modulus decreases Also It was found that the thermo-mechanical treatment at 260 ◦C gave better properties , 2%in recovery strain , increase hardness due to the formation of martensitic phase and austenite phase in structure.


Article
Mechanical Properties of Self Compacting Concrete Made with Local Materials
الخواص الميكانيكية للخرسانة ذاتية الرص المعمولة من المواد المحلية

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Abstract

The main objective of this research is to investigate the properties of fresh and hardened self-compacting concrete (SCC) made from locally available materials in Basrah governorate-Iraq. The study consists of investigation the influence of volume ratio of coarse aggregate, limestone powder (LSP) to total powder ratio, and powder/water ratio. This is to obtain more information which will contribute to a better understanding to the use of local materials in production of SCC. To achieve these aims, 18 different mixes (17 SCC mixes and one normal concrete (NC) mix were prepared, tested and evaluated. It has been noticed that, with the same W/C ratio, SCC mixes prepared with higher coarse aggregate volume ratio showed higher strengths and modulus of elasticity than mixes prepared with lower coarse aggregate volume ratio. The increment of LSP as a replacement of cement leads to lower strengths and static modulus of elasticity. For the same compressive strength at 28 days, SCC showed 11%, 20% and 26.4% higher flexural, splitting tensile and bond strengths than NC respectively.

الهدف الرئيسي لهذا البحث هو التحري عن خواص الخرسانة ذاتية الرص الطرية والمتصلبة المعمولة باستخدام المواد المتوفرة في محافظة البصرة- العراق. البحث يحتوي دراسة تأثير النسبة الحجمية للركام الخشن و نسبة مسحوق الحجر الجيري إلى الوزن الكلي للمسحوق، و نسبة الماء الى المسحوق على الخواص الطرية والمتصلبة للخرسانة ذاتية الرص وذلك للحصول على مزيد من المعلومات التي تساهم في فهم أفضل لاستخدام المواد المحلية في صناعة الخرسانة ذاتية الرص ,ولتحقيق هذه الأهداف، تم تجهيز وفحص وتقييم 18 خلطة (17 خلطة خرسانة ذاتية الرص وخلطة واحدة خرسانة اعتيادية). لوحظ أنه لنفس نسبة الماء إلى الاسمنت، الخرسانة ذاتية الرص التي أعدت باستخدام نسبة حجمية اعلى للركام الخشن أظهرت ارتفاع المقاومات ومعامل المرونة بالمقارنة مع نظيرتها التي أعدت مع نسبة حجمية اقل للركام خشن. الزيادة في نسبة مسحوق الحجر الجيري كبديل للإسمنت ادت إلى انخفاض المقاومات، ومعامل المرونة والانكماش، ولكن مع امتصاص اعلى .لنفس مقاومة انضغاط في عمر 28 يوم، الخرسانة ذاتية الرص اظهرت مقاومة انحناء ومقاومة شد انشطاري ومقاومة ترابط اعلى ب 11% و 20 % و26.4% من الخرسانة الاعتيادية على التوالي.


Article
EVALUATION OF MECHANICAL PROPERTIES OF HIGH PERFORMANCE SELF-CONSOLIDATED CONCRETE ENHANCED BY DISCRETE STEEL AND POLYPROPYLENE FIBERS
تقييم الخواص الميكانيكية للخرسانة عالية الأداء الذاتية الرص المعززة بالألياف الحديدية المنفصلة وألياف البولي بروبلين

Author: Ali Adel Abdulhameed
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 4 Pages: 34-52
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

High performance self-consolidating concrete HP-SCC is one of the most complex types of concrete which have the capacity to consolidated under its own weight, have excellent homogeneity and high durability. This study aims to focus on the possibility of using industrial by-products like Silica fumes SF in the preparation of HP-SCC enhanced with discrete steel fibers (DSF) and monofilament polypropylene fibers (PPF). From experimental results, it was found that using DSF with volume fraction of 0.50 %; a highly improvements were gained in the mechanical properties of HP-SCC. The compressive strength, splitting tensile strength, flexural strength and elastic modulus improved about 65.7 %, 70.5 %, 41.7 % and 80.3 % at 28 days age, respectively with retaining the main properties of HP-SCC. Furthermore, using PPF with volume fraction up to 0.10 %; an enhancement in the compressive and elastic modulus of HP-SCC about 47.4 % and 31 % was obtained at age of 28 days, respectively. Moreover, using PPF with volume fraction of 0.15 %, the splitting tensile strength and flexural strength of HP-SCC improved about 44.5 % and 20.3 %, respectively.

تعتبر الخرسانة العالية الأداء والذاتية الرص واحدة من أعقد أنواع الخرسانة التي لها القابلية على الرص تحت تأثير وزنها الذاتي فضلاً عن تجانسها الممتاز وديمومتها العالية. هذه الدراسة العملية تهدف إلى إستخدام أبخرة السليكا كمنتج صناعي ثانوي في إنتاج الخرسانة عالية الأداء والذاتية الرص والمعززة بألياف حديدية منفصلة وألياف البولي بروبلين أحادية الشعيرة. بينت نتائج الفحوصات العملية، إن أستخدام الألياف الحديدية المنفصلة بنسبة 0.5 % من حجم الخرسانة أدى إلى تحسن عالي في الخواص الميكانيكية لها حيث زادت كل من مقاومة الأنضغاط ، مقاومة إنفلاق الشد، مقاومة الإنثناء و معامل المرونة بنسبة 65.7 % ، 70.5 % ، 41.7 % ، 80.3 % وعلى الترتيب لمعدل النماذج الخرسانية المختلفة وبعمر 28 يوماً. علاوة على ذلك، إن أستخدام ألياف البولي بروبلين أحادية الشعيرة بنسبة لاتتجاوز 0.10 % من حجم الخرسانة أدى إلى زيادة مقاومة الأنضغاط ومعامل المرونة للخرسانة عالية الأداء والذاتية الرص بنسبة 47.4 % ، 31 % بعمر 28 يوماً، على الترتيب. أيضاً، إن أستخدام الألياف الأخيرة بنسبة حجمية مقدارها 0.15 % أدى إلى تحسن مقاومة إنفلاق الشد ومقاومة الإنثناء للخرسانة وبعمر 28 يوماً لمعدل النماذج الخرسانية المختلفة بنسبة 44.5 % ، 20.3 %، على الترتيب.


Article
Improvement of mechanical properties of polyvinyl alcohol by addition of biomaterial (Okra shell and peel peas) for production of environmentally friendly products

Author: Falak O. Abas
Journal: Mesopotamia Environmental Journal بيئة وادي الرافدين ISSN: 24102598 Year: 2016 Volume: 2 Issue: 4 Pages: 1-8
Publisher: Babylon University جامعة بابل

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Abstract

A bio-based automotive parts are currently astonishing applied such as, DaimlerChrysler of biggest proponent with up to 50 components in its European vehicles. The properties of natural fibers are closely related to the nature of cellulose and its crystallinity properties. Where, fibers with higher cellulose content possess impressive specific mechanical properties.In making of natural fibers composites, the natural fibers are usually collected, dried, ground and sieved to obtain the desired size prior to processing between (125-250) μm. The processing method that used to prepare natural fiber based composites is moulding ,where the natural fiber for new composites are processing at low temperature limited to 100OC with a shorter processing time reached 24hr in order to avoid the degradation of natural fibers.PVA/natural fibers green composites processing methods and applications in various fields have been investigated. From results these green composite based on okra shell and peel Pease fibers reinforced PVA composites showed good fiber/matrix bonding and exhibited high tensile strength with the maximum fiber content in addition to other mechanical properties as (impact strength, compression strength, and bending distortion) with preference to the combined fibers composite that selected to be a best optimum one.


Article
Preparation of Metal Organic Compounds containing Schiff Bases and Study Some of its Mechanical Properties

Authors: Abdulazeez O. Mousa --- Ali Jassim Al-Zuhairi --- Zainab Mkee Abid --- Jassim M. Salman --- et al.
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2016 Volume: 24 Issue: 3 Pages: 701-711
Publisher: Babylon University جامعة بابل

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Abstract

This research included preparation of complexes for Ni ion chloride(II) Cr ion chloride(III) and aqueous iron chloride (III) with Schiff bases ligand (N, N) di methyl of the amino Benzaldhyde. The prepared complexes were characterized by IR, UV and visible spectra. Also the mechanical properties by technique of ultrasonic waves velocity at 40 KHz frequency were studied include the ultrasonic waves velocity, absorption coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance compressibility, and bulk modules. The Results showed that all properties decrease with increase the ultrasonic waves velocity except the specific acoustic impedance and bulk modules which directly proportional to the velocity and all the results were compared with with those for similar compounds.

تضمن هذا البحث تحضير معقدات لايون النيكل الثنائي التكافؤ((II والكروم المائي الثلاثي التكافؤ (III) وايون الحديد الثلاثي التكافؤ (III) مع ليكاند (المادة الحرة) قاعدة شف –N‘N)]ثنائي مثيل أمينو بنزلديهايد [(. تم تحليل المعقدات المحضـرة بوساطة طيف الأشعة تحت الحمراء وطيفي الأشعة فوق البنفسجية والمرئية , كما اشتمل البحث على دراسة الخصائص الميكانيكية بوساطة تقنية الموجات فوق الصوتية وبتردد KHz(40), فقد تم قياس سرعة هذه الموجات ومعامل الامتصاص وزمن وسرعة الاسترخاء والممانعة الصوتية النوعية والانضغاطية ومعامل المرونة وأظهرت النتائج إن جميع هذه الخصائص تتناقص مع زيادة السرعة ماعدا الممانعة الصوتية ومعامل المرونة فإنها تزداد بزيادة السرعة وقد قورنت جميع النتائج مع مركبات شبيهة .


Article
The Effect of Ferrite Content on the Thermomechanical and Dielectric Strength Properties of Epoxy Composite
تأثير التقوية بالفرايت على الخواص الحرارية و الميكانيكية ومقاومة العزل لمتراكبات الايبوكسي

Authors: Lamees S. Faiq --- Zahraa F. Attiyah
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 1 Part (A) Engineering Pages: 186-192
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Different concentrations of cadmium ferrite (2%, 5%, 8%, 10% and 15%) were incorporated into epoxy resin. Cadmium ferrite was prepared by conventional ceramic technique. Composites are prepared by mixing the ferrite with epoxy by hand lay - up method at different percentages. The effect of ferrite content on tensile strength, hardness, thermal properties such thermal conductivity, thermal diffusivity and specific heat beside the dielectric strength were investigated. Using ferrite powders as filler to form particulate composite could lead to composite properties improvement. All the measured properties were improved with the increasing of the filler content. The results showed the important role of perfect adhesion between the filler and the polymer on the composite properties. It is found that the uniform distribution of filler particles in all directions of composite leads to the improved properties.

تراكيز مختلفة من الكادميوم فرايت (2%, 5%, 8%, 10%, 15%) ادرجت في راتنج الايبوكسي. الكادميوم فرايت اعد بتقنية السيراميك التقليدية . المتراكبات تم تحضيرها عن طريق خلط الفرايت مع الايبوكسي بالطريقة اليدوية وبنسب مختلفة . تم دراسة تأثير محتوى الفرايت على خواص الشد والصلادة والخواص الحرارية مثل التوصيلية الحرارية , الانتشلر الحراري , الحرارة النوعية بالاضافة الى مقاومة العزل. استخدام مساحيق الفرايت كتقوية لتكوين المتراكبات ادى الى تحسين خواص هذه المتراكبات . جميع الخواص التي تم قياسها تحسنت مع زيادة محتوى التقوية. اظهرت النتائج الدور المهم للالتصاق ما بين التقوية والبوليمر على خواص المتراكب. وقد وجد ان التوزيع المنتظم لدقائق الحشوة في جميع اتجاهات المتراكب يؤدي الى تحسين الخواص .


Article
Study the Effect of Mica as Filler in Natural Rubber properties

Author: Abeer Adnan Abd
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2016 Volume: 24 Issue: 3 Pages: 773-781
Publisher: Babylon University جامعة بابل

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Abstract

In the current, Studying the effect of mica upon the characteristics of curing system of natural rubber (NR) rubber has been carried out by using oscillating disk rehometer according to the ASTM D-2084 specification. Results indicate that the addition of cheap material (Mica) to natural rubber in proportions of (4, 8, 12, 16, and 20) % of mica enhanced the hardness, the tensile strength and reometric properties of the rubber. The mix of NR/mica (100: 20) shows promising mechanical properties than other composition. The result showed that the curing time, scorch time and minimum torque decreased with filler content increase therefore the processing time decreased. Also the tensile strength, maximum torque, specific density and hardness advanced with the filler content increase. The hardness developed significantly from (40) to (46) shore (A) when mica content was increased therefore the modulus increased and the elongation decreased. The maximum tensile strength and the minimum wear rate at (10) % of mica.

في البحث الحالي تم دراسة تاثيرالمايكا على خواص الانضاج لمطاط NR ) ) وذلك باستخدام reometric oscillating disk وطبقا للمواصفة العالمية ASTM D2084 اظهرت النتائج ان اظافة الماكا الرخيصة الثمن لمطاط NR ) ) وبنسب ( 20,16,12,8,4)% حسنت الصلادة و مقاومة الشد و خواص الانسياب للمطاط. ان خلط المايكا مع المطاط بنسبة (20/100) قد اظهر الخواص الميكانكية المرغوب بها اكثر من باقي النسب . النتائج اظهرت ان زمن الانضاج والاصلاد العزم الاصغر يقل مع زيادة محتوى المالى لذلك زمن التصنيع يقل .بالاضافة الى ذلك ان مقاومة الشد والعزم الاكبر والكثافة النوعية تزداد مع زيادة محتوى المادة المالئة و الصلادة تطورت بشكل ملحوظ من (40-46shore A(عندما تضاف المايكا لذلك معامل المرونة يزداد والاستطالة تقل.اكبر مقاومة شد واقل معدل بلى يحدث عند اضافة (10)% من المايكا.


Article
EFFECT OF Ti AND Sn ADDITIONS ON MECHANICAL PROPERTIES OF ALUMINUM- SILICON - COPPER ALLOY
تأثير اضافة Ti و Sn على الخواص الميكانيكية لسبيكة الومنيوم – سليكون - نحاس

Authors: Muhammad A. Fakhri --- Israa A. Alkadir اسراء عبد القادر عزيز
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2016 Volume: 9 Issue: 4 Pages: 48-61
Publisher: Diyala University جامعة ديالى

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Abstract

This research is devoted to study the effect of adding alloying elements (Ti and Sn) with different percentages (1, 3 and 5) wt% on the microstructure, mechanical properties, and dry sliding wear resistance of Al-6.9wt%Si-1.7%Cu alloy.The particle size of Ti powder is 200 µm, but the Sn adding as a small bits to the alloy. The microstructures were examined with optical microscope for the base alloy before and after adding alloying elements. This examination showed that the changing occurs on the morphology of grain, precipitated intermetallic compounds and other phases (TiAl, TiAl2, Al2Cu and β-Sn) determined by the x-ray diffraction. The mechanical properties studied in this research were the tensile strength, impact toughness, and hardness. The results depicted that the ơu, ơy and hardness increase with increasing the percentage of Ti, while they decrease with increase the percentage of Sn. On the other hand, the alloys with Ti additions revealed that El% decrease with increasing Ti additions, but El% increase with increasing the Sn addition to the base alloy. Also, the impact toughness, was examined, and it was found alloying element was lower than the base alloy for both elements (Ti and Sn). The pin-on-disk technique was used to determine the wear resistance for base alloy before and after adding the alloying elements. The wear resistance increased with increasing the percentage of the Sn, but it decreased with increasing the percentage of Ti at different applied loads (2.5, 5 and, 7.5) N at a constant sliding speed of (3.7) m/sec.


Article
High Performance Concrete Improvement by Styrene-Butadiene Rubber Addition

Authors: Alaa Abdulhasan Atiyah --- Saad B. H. Farid --- Ahmed Saad Kadhim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 12 Part (A) Engineering Pages: 2296-2309
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper, the properties of high performance concretes modified by polymer were studied. Liquid synthetic styrene-butadiene rubber (SBR) was added (5%, 10% and 15%) by weight of cement to high performance concrete (HPC) to elucidate the effect of the polymer additive to their properties.The compressive strength, splitting tensile strength, flexural strength, porosity, dry density and total water absorption were measured.Thermal conductivity, thermal diffusivity and specific heat of HPC isalso measured. In addition, SEM micrographs are compared reference and polymer modified HPC.The results show that there is an improvement in the workability for HPC after the addition of the polymer. Furthermore, the density of the set concrete was increased and both the porosity, total water absorption was decreased. Thermal conductivity, thermal diffusivity, and specific heat show improvement after polymer addition, which indicate better endurance.The SBR modified HPC, exhibits a significant improvement in splitting tensile strength and flexural strength, although it was at the expense of the compressive strength to some extent.The HPC has shown balanced microstructure before and after the addition of polymer, although they noticed improved on the ductile properties.


Article
Mechanical Performance of CO2 and Autoclave Cured Date Palm Fiber Reinforced eco-mortar Composites

Authors: Maan Salman Hassan --- Wahad Marwan Salih
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 14 Part (A) Engineering Pages: 2754-2765
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Using nature waste fibers in construction industries had shown important character "environmental friendly" which paid a great interest around the world. The aim of this paper was to investigate the suitability of agriculture waste date palm fibers as lignocellulosic materials for the production of wood-cement composite, in addition to enhance their compatibility with cement using accelerated curing like carbonation or autoclave.Three percentages of date palm fibers were used (2, 6, and 10)% by weight of cement in cement composites specimens. Compressive, flexural and direct tension strengths were examined as strength properties and X-ray diffraction (XRD) as microstructure properties. The results show that carbonation curing was the most effective curing for compressive strength property while autoclave curing leads to better performance in flexural strengths. Curing type effects on direct tension property were fluctuated. This could be attributed to the variation in cellulose fiber roles with respect to each property evaluated. X-ray diffraction confirmed that CO2-curing led to increased CaCO3 content compared with autoclaved composites.

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