research centers


Search results: Found 8

Listing 1 - 8 of 8
Sort by

Article
Studying and Modeling The Effects of Quartz Addition and Heat Treatment on Corrosion Properties of Ceramic Coating

Authors: Ali H. Ataiwi --- Ibtihal A. Mahmood --- Jabbar H. mohmmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 12 Pages: 2564-2579
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, by using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results of corrosion resistance tests indicated that the acid resistance was greatly improved by addition of quartz into enamel frit but at same times decreased the alkali corrosion resistance, while the heat treatments improved both acid and alkali resistance for all cases, this is attributed to the formation of complex network from crystalline phases. The results also indicated that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for acid resistance property which are improved by 86.66%, while the optimum values for alkali resistance property was brought with free quartz added samples which were treated at 600˚C for 120min. Mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the experimental data for acid and alkali corrosion rate. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (82.58%, and 96.7%) for acid and alkali resistance properties respectively.


Article
Wear Resistance of a New Glass Ceramic Coating
مقاومة البلى لطلاء سيراميك زجاجي جديد

Authors: Jabbar H. mohmmed --- Ibtihal A. Mahmood --- Ali H. Ataiwi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 6 Part (A) Engineering Pages: 1472-1484
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

A new wear resistance glass-ceramic coating system iron (low alloyed low carbon steel) based substrate was developed. The effects of heat treatment conditions and mill additions on wear resistance of developed coatings resistance were studied. The coating materials showed excellent properties for protection the iron substrate from wear. Also, in this work mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the experimental data for wear rate. Comparing the predicted and measured values gives high prediction accuracy.

في هذا البحث تم تطوير طلاء سيراميك زجاجي جديد مقاوم للبلى لمعدن الحديد(فولاذ منخفض السبك منخفض الكاربون) كمادة اساس. تم دراسة متغيرات المعاملة الحرارية زاضافات الطحن على مقاومة البلى للطلاءات المطورة. ابدى الطلاء المستخدم خواص حماية ممتازة لمادة الاساس الحديد ضد البلى. كذلك في هذا البحث تم عمل موديل رياضي وتم الحصول على معادلات انحدار باستخدام برنامج (SPSS) للتنبأ بالبيانات العملية لمعدل الطلاء. اعطت مقارنة النتائج المقاسة بالنتائج المتنبئة دقة تنبأ عالية.


Article
Modeling of The Corrosion Behavior of Enamel Coatings in Different Aggressive Media
نمذجة سلوك التاكل لطلاءات المينا في اوساط اكالة مختلفة

Authors: Ibtihal A. Mahmood --- Jabbar H. mohmmed --- Bayda'a A. Khalaf
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 6 Part (A) Engineering Pages: 1530-1543
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In this study an attempt has been made to formulate materials for glass ceramic enamel coating that can be applied directly onto cast iron substrate for corrosion control. Different 'proportions(4.95) %wt. to form four batches. The batches were mixed with water to form slips which were used to coat already prepared cast iron surfaces and were allowed to dry in the oven. The coated cast iron plates were fired at temperatures of 850˚C to mature and factually heat treated at 680˚C. The coatings were observed and also chemical tests were conducted to determine the corrosion properties of the resultant coatings. The chemical tests were evaluated using a suitable standard methods and special attention was paid to the type of aggressive solution, and temperature.The results show that the coatings matured and adhered very well to the sub strateand showed good corrosion resistance in H2SO4,HCl,C6H8O7, H3PO4, and NaOH solutions. The results indicated that the corrosion rate in both acid and alkali media was increased strongly with the increasing temperature.The coatings prepared with the zircon showed better results in terms of acidcorrosion resistance than those prepared with the other crystalline agents. However, the corrosion rate of the zircon containing coating in sulfuric acid was higher than that in hydrochloric acid. Also, it is found that there is absolutely no weight loss for any of the four types of the coating in neither citric nor phosphoric acids. At the same time, the results for alkali corrosion resistance indicate that the act of the four series is very similar to each other, for the four coatings there is no high corrosion rate until the temperature exceed 100˚C after that the rate increases in a very quick manner. From the results it is found that the enamel with lithium oxide was not affected by the alkali solution at all, this behavior is associated with the presence of crystalline β-Spodumene, and β-Eucryptite, which have an extremely high corrosion resistance especially for alkali medium. Mathematical modeling is implemented and regression equations are obtained by using (SPSS) software to predict the experimental data for acid and alkali corrosion rate. Comparing the predicted and measured values gives high prediction accuracy.

في هذه الدراسة تم عمل محاولة لتكوين خلطة مواد مناسبة لطلاءات السيراميك الزجاجي والتي يمكن استخدامها بصورة مباشرة على الحديد الزهر للسيطرة على التآكل. تم اضافة عوامل تبلور مختلفة(Li2O،TiO2، ZrSiO4، و CaO.Al2O3.2SiO2) وبنسب ثابتة (4.95)% لتكوين اربع خلطات. تم خلط هذه الخلطات مع الماء لتكوين مادة الطلاء ال(slip) والتي يتم بها طلاء اسطح حديد الزهر المحضرة ثم تترك لتجف في فرن التجفيف. بعدها الواح الحديد الزهر المطلية تحرق عند درجة 850مْ للاندماج واخيرا تعامل حراريا عند درجة 680مْ.الطلاءات تم ملاحظتها وكذلك تم اجراء الفحوص الكيميائية عليها لتحديد خواص التاكل لها. تم اجراء الفحوص الكيميائية باستخدام طرق قياسية ملائمة وتم توجيه انتباه خاص لنوع المحلول الاكال المستخدم وكذلك لدرجة الحرارة. بينت النتائج ان الطلاءات قد اندمجت والتصقت بصورة جيدة جدا بالمعدن الاساس واظهرت مقاومة تاكل جيدة في المحاليل (H2SO4، HCl، C6H8O7، H3PO4، وNaOH). بينت النتائج ان معدل التاكل قد ازداد بصورة كبيرة مع زيادة درجة الحرارة في كلا من الاوساط الحامضية والقاعدية. اظهرت النتائج كذلك ان الطلاءات المحضرة من الزركون لها خواص افضل من ناحية مقاومة التاكل الحامضي مقارنة مع الطلاءات الاخرى. لكن معدل التاكل للطلاءات المحتوية على الزركون في حامض الكبريتيك يكون اعلى منه في حامض الهايدروكلوريك. كذلك، وجدنا عدم حدوث أي فقدان بالوزن للطلاءات الاربعة في حامض النتريك او الفسفوريك. في نفس الوقت بينت نتائج مقاومة التاكل في المحاليل القاعدية ان السلوك كان متشابه جدا للطلاءات الاربعة، حيث لم يلاحظ أي معدل تاكل عالي حتى درجة 100مْ بعدها ازداد معدل التاكل بصورة سريعة جدا. وقد وجدنا من خلال النتائج ان الطلاء الحاوي على اوكسيد الليثيوم لم يتاثر بالمحلول القاعدي بصورة تامة، وهذا نتيجة وجود الاطوار البلورية (β-Spodumene، وβ-Eucryptite) والتي لها مقاومة تاكل عالية جدا وخصوصا للاوساط القاعدية. تم أيضا استخدام موديل رياضي و تم الحصول على معادلات انحدار باستخدام برنامج (SPSS)والتي تكونت لغرض التنبؤ بالبيانات المختبرية لخواص الطلاء. بينت النتائج من خلال المقارنة بين القيم المتنبئة والحقيقية إن هذا البرنامج يعطي دقة تنبؤ عالية.


Article
Studying and Modeling the Effects of Quartz Addition and Heat Treatment on Mechanical Properties of Glass-Ceramic Coating
دراسة ونمذجة تأثيرات اضافة الكوارتز والمعاملة الحرارية على الخواص الميكانيكية لطلاء الزجاج السيراميكي

Authors: Ali H. Ataiwi --- Ibtihal A. Mahmood --- Jabbar H. mohmmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 7 Part (A) Engineering Pages: 1811-1824
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results showed the suitability of this coating for protection the metal substrate which was used in present work. The results of tests also indicated that the mechanical properties ( hardness, adhesion strength, and thermal stability) of resultant coating were greatly improved by both addition of quartz into enamel frit and heat treatments for all cases, this is attributed to the formation of complex network from crystalline phases(Li2SiO3, Li2TiSiO5, NaAlSi2O6, and SiO2) which are the main phases in the resultant glass-ceramic coating. It has been found that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for ( hardness, adhesion strength, and thermal stability) of resultant coating which are improved by (70.58%, 33.84%, and 39.68%) respectively. Mathematical modeling is implemented and regression equations are obtained using ( SPSS ) software to predict the experimental data for mechanical properties of resultant coating. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (98%, 98.5%, and 97.4%) for ( hardness, adhesion strength, and thermal stability) respectively.

في هذا العمل تم تطوير طلاء سيراميكي جديد واستخدامه، كطبقة طلاء واحدة بدون معاملة كيميائية مسبقة للسطح، باستخدام طريقة التغطيس على المعدن الاساس. صمم الطلاء للاستخدام على الانواع المختلفة للفولاذ المنخفض السبك، المادة الاساس المختارة كانت فولاذ منخفض السبك منخفض الكاربون (0،2)% كاربون. تم استخدام معاملات حرارية مختلفة عند درجات حرارة (500، 550، 600) درجة مئوية وبازمان مختلفة(60، 120) دقيقة مع اضافات كوارتز بحدود (0-15)% للحصول على الخواص المثلى لطلاء السيراميك الزجاجي. تم توصيف هذه الطلاءات باستخدام تحليل حيود الاشعة السنية حيث اثبتت النتائج وجود عدد من الاطوار البلورية الدقيقة والتي تكونت خلال المعاملات الحرارية. بينت النتائج ملائمة هذا الطلاء لحماية المعدن الاساس المستخدم في هذا العمل. كذلك بينت نتائج الاختبارات ان الخواص الميكانيكية ( الصلادة، متانة الالتصاق، والاستقرارية الحرارية) للطلاءات الناتجة قد تحسنت بصورة كبيرة من خلال كلا من اضافة الكوارتز الى مادة الطلاء (الفرت) وكذلك من خلال المعاملة الحرارية وفي جميع الحالات. هذا التحسن مرتبط بتكون شبكة معقدة من الاطوار البلورية (Li2SiO3 Li2TiSiO5, NaAlSi2O6, and SiO2) والتي كانت الاطوار الرئيسية في طلاءات السيراميك الزجاجي الناتجة. وقد وجد ان المعاملة الحرارية عند (600) درجة مئوية واضافة (15)% كوارتز قد جاءت بالقيم المثلى ل (الصلادة، متانة الالتصاق، والاستقرارية الحرارية) للطلاء الناتج حيث تحسنت بنسبة (70،58%، 33،84%، و 39،68%) على التوالي. تم استخدام موديل رياضي والحصول على معادلات الانحدار باستخدام برنامج(SPSS) للتنبا بالبيانات العملية للخواص الميكانيكية للطلاء الناتج. اعطت المقارنة بين قيم النتائج المنتبئة والمقاسة دقة تنبأ عالية. حيث كانت دقة التنبأ (98%، 98،5%، و 97،4%) لخواص (الصلادة، متانة الالتصاق، والاستقرارية الحرارية )على التوالي.


Article
Experimental Study for the Effects of Crystalline Agents on Properties of Glass-Ceramic Coating

Authors: Ibtihal.A. Mahmood --- Ahmed.A.Zainulabdeen --- Jabbar.H. Mohmmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 2 Part (A) Engineering Pages: 179-184
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In this work, four series of glass-ceramic coatings were developed and applied by using the dipping technique to cast iron sheets. The influence of different types of crystallization agents (Li2O, TiO2, ZrSiO4, and CaO.Al2O3.2SiO2) was investigated in relation to the mechanical features of the coatings. The resultant coating is characterized using X-ray diffraction analysis. The properties of micro-hardness and adhesion strength are evaluated using suitable standard tests. The X-ray analysis of resultant coatings showed the existence of some of crystalline phases formed depending on the type of the crystallization agent. The results also indicated that the coating properties were strongly dependent on composition and concentration of crystallization agent. Coating with feldspar gives the highest value of hardness and adhesion index. In general, properties of the resultant coatings were improved in all cases; this is related to the formation of a complicated network from crystalline phases.


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

Loading...
Loading...
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
Effect of Annealing Treatment on the Anisotropy Behavior of Cold Rolled Stainless Steel 304 Sheets

Authors: Ahmed A. Zainulabdeen احمد عميد زين العابدين --- Jabbar H. Mohmmed --- Najmuldeen Y. Mahmood
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2018 Volume: 11 Issue: 2 Pages: 84-89
Publisher: Diyala University جامعة ديالى

Loading...
Loading...
Abstract

Anisotropy of materials has harmful effects during deep drawing operations and reduce it will strongly enhance the productivity and quality of deep drawing yields. In this work the effect of annealing treatment on texture and anisotropy behavior of cold rolled stainless steel 304 sheets were investigated. Uniaxial tensile test samples cut at 0o, 45o and 90o to the rolling direction were prepared in order to measure the anisotropy parameters (normal anisotropy, r_n, and planar anisotropy, ∆r). Two annealing temperatures (1050, and 1150) °C were used to study their effects on anisotropy behavior. The results show that the normal anisotropy value of annealed samples at 1150°C increases by (31%) as compared to the received samples. This indicates that the annealed samples at 1150 °C have the highest formability. Also, results show significant reduction (about 88.7%) in planar anisotropy value for 1150°C annealed samples. This gave rise to an increase in deep drawing yield.


Article
THE EXPERIMENTAL STUDY AND MATHEMATICAL MODEL OF THE EFFECT OF ALUMINA PARTICLES REINFORCEMENT ON MECHANICAL PROPERTIES OF EPOXY
دراسة عملية وموديل رياضي لتأثير التقوية بدقائق الالومينا على الخواص الميكانيكية للايبوكسي

Loading...
Loading...
Abstract

This article describes some mechanical properties of alumina-filled epoxy composites. In this work, the epoxy matrix was reinforced with increasing amount of alumina particles in the range of 0-40% by weight with different particle size (d≤8, 18≤d≤25, 33≤d≤45, 50≤d≤62)µm. From the flexural test results, it was observed that the flexural modulus increases with increasing α-alumina content from 10 to 40 wt%. At the same time, the results indicated that there are no much effect on the flexural modulus with change the particle size in the range of (d≤8, 18≤d≤25)µm. The highest value of flexural modulus was recorded with 40 wt% of α-alumina content and (d≤8)µm particle size. It was also found that the 40 wt% alumina content and (d≤8)µm particle size recorded the highest value of fracture toughness (Gc), fracture toughness (Kc), hardness (HB), and wear resistance which were improved by (253%, 282%, 230%, and 82%), respectively. Also, in this work a mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the properties of alumina filled epoxy composites. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (90.13%, 85.95%, 90.28%, 89.76%, and 84.36%) for flexural modulus, toughness, fracture toughness, hardness, and wear rate respectively.

يصف هذا ألبحث بعض الخواص الميكانيكية لمتراكبات الايبوكسي المقواة بدقائق الالومينا. حيث تم في هذا البحث اضافة دقائق الالومينا لتقوية راتنجات الايبوكسي بنسب وزنية مختلفة (0-40)% مع احجام حبيبية مختلفة (d≤8, 18≤d≤25, 33≤d≤45, 50≤d≤62) مايكرومتر. بينت نتائج اختبار الانحناء زيادة قيمة معامل الانحناء بزيادة نسبة الالومينا. وفي نفس الوقت بينت النتائج عدم وجود تأثير كبير لتغيير الحجوم الحبيبية في حدود(d≤8, 18≤d≤25)مايكرومترعلى قيمة معامل الانحناء. أعلى قيمة لمعامل الانحناء تم الحصول عليها عند اضافة الالومينا بنسبة40 % من الوزن بحجم حبيبي (d≤8) مايكرومتر. من ناحية اخرى فقد وجد ايضا أن اعلى القيم للمتانة, متانة الكسر, الصلادة, ومقاومة البلى والتي تحسنت بمقدار( 253%، 282%، 230%، و82% ) على التوالي قد سجلت ايضا عند اضافة الالومينا بنسبة40 % وحجم حبيبي (d≤8) مايكرومتر. تم ايضا في هذا البحث استخدام موديل رياضي وتم الحصول على معادلات الانحدار باستخدام برنامج (SPSS) لغرض التنبؤ بخواص متراكبات الايبوكسي المقواة بالالومينا. بينت النتائج من خلال المقارنة بين القيم المتنبئة والحقيقية إن هذا البرنامج يعطي دقة تنبؤ عالية. فقد كانتدقة التنبؤ بمقدار (90.13%, 85.95%, 90.28%, 89.76%, 84.36%) لمعامل الانحناء، المتانة،ومتانة الكسر، الصلادة، ومعدل البلى على التوالي.

Listing 1 - 8 of 8
Sort by
Narrow your search

Resource type

article (8)


Language

English (8)


Year
From To Submit

2018 (2)

2016 (1)

2014 (4)

2011 (1)