البحث — المستودع الرقمي العراقي

نتائج البحث: 25 من أصل 68

الحماية من التاكل لقواعد الاعمدة الكهربائية في الترب ذات المقاومية المنخفضة == Corrosion Protection of Electrical Bar Stands In Low Resistivity Soil

اسم المؤلف: اياد نصيف جاسم

اسم المشرف: سامي ابراهيم جعفر الربيعي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: يستخدم الفولاذ المغلون في تصنيع الاعمدة الكهربائية لامتلاكه خواص ميكانيكية جيدة ومقاومة تاكل عالية. وتحت الظروف الاعتيادية يعاني العمود من التاكل بعد عدة سنوات من الخدمة.يصنع عمود الكهرباء من فولاذ St - 52 والمطابق للمواصفة DIN الالمانية ويتالف من ثلاثة | Galvanized steel is used in electrical poles because of the good combination of its mechanical properties and the corrosion resistance. Under normal conditions, electrical pole suffered from corrosion after some years in service. Electrical poles, which were made according to Germany standard DIN st.52, consist of three parts; the upper, mid and lower part. This study focuses on the last part because the surrounding soil of electrical pole is more corrosive than the atmospheric environment, which surrounds to other two parts of the electrical pole. Soil resistivity is the one variable that has the greatest influence on corrosion rate. Electrical poles which at buried in low resistivity soils will generally be anode, whereas electrical poles buried in adjacent high resistivity soils will generally low corrosion.The electrolyte in this work was prepared according to the values of Iraqi soil resistivity. Sodium chloride (NaCl) was used in different concentrations of (2, 2.5, 3 and 3.5) wt. %, which are equivalent to 27, 24, 20 and 18 ohm.cm. Two methods were used in this work in order to improve corrosion resistance, the first method galvanizing process in different thicknesses (80, 90,100,110,120 and130) µm and the second method is coating by different types of Iraqi paints (D - 5547) with hardener (H - 1457)and(G - 5532,G - 5533,D - 5542) with hardener(H - 5533) The corrosion rate and corrosion potential of steel increases and decreases with the increase in NaCl wt.% concentration respectively. Corrosion rates (mpy) with coating thickness are achieved as a function of environment in different soil resistivities. The more corrosion resistance occurs at 120 µm galvanized layer. Micro cracks appear at 130 µm galvanized thickness.In this work, two mixed ratios of paint and hardener were used. These ratios are 2 : 1 and 1 : 1. Paint with mixing ratio equal to 2 : 1 of G - 5532 + G 5533and mixing ratio 1 : 1 D 5542 with hardener 5530 gave the more corrosion resistance.The coating thickness has a direct influence on the performance or life of the electrical pole. As the thickness of galvanized layer increases, the life of protection increases until 120 µm. The life of a zinc coating is a linear function of coating weight for any specific environment. The efficiency of coated electrical pole either by galvanization or paint process was a proximately between 94% to 97% and 98% to 99.6% respectively.

سلوك المواد فائقة اللدونة ذات البنية المجهرية الناعمة لسبيكة المغنيسيوم نوع AZ31B والمشكلة بواسطة التشكيل العالي الانفعال == Superplastic Behavior of Fine Grained AZ31B Magnesium Alloy Processed By Severe Plastic Deformation

اسم المؤلف: زياد طارق عبد الوهاب

اسم المشرف: ازل رفعت اسماعيل

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: Superplastic properties and microstructure evolution of commercial AZ31B magnesium alloy processed by two different severe plastic deformation methods Equal Channel Angular Pressing (ECAP) and Equal Channel Angular Rolling) ECAR) were studied. Samples were tested in tension at temperature of 623 K and strain rate ranging from 2.4×10 - 4 1×10 - 2 s - 1. ECAP die with 10 ×10 mm cross section channel, oblique angle of ?=90° and ?=13° was designed to refine the alloy microstructure at temperature of 473 K using route BC. Application of ECAP showed a remarkable grain refinement for AZ31B Mg alloy from 14.1 to 2.1?m after three ECAP passes. Maximum superplastic elongation of 261% was achieved at 623 K and strain rate of 2.45×10 - 4 s - 1. The measured strain rate sensitivity was m = 0.33 demonstrating that viscous glide control creep was the dominant deformation mechanism. In most investigation used ECAR process, the die temperature was set to room temperature, in order to avoid cracking intermediate annealing was used for AZ31B Mg alloy which has poor formability at room temperature. This is caused by a lack of active slip systems, especially in the <c+a> direction. However, in this study a special isothermal ECAR die capable of operating without intermediate annealing was used to process AZ31B Mg alloy. The ECAR was carried out at 623 K using a die of ?115 ° channel angle and without rotation. Processing by ECAR showed less effect on the microstructure refinement where the grain size was reduced from 10?m to 4.2?m after six ECAR passes. ECAR increases the yield and ultimate stress and decreases the elongation corresponding to increasing the number of ECAR passes, the as - received material exhibits large amount of superplastic elongation compared to ECAR processed specimens. Therefore superplastic behavior of the AZ31B magnesium alloy was evaluated at temperatures 623 K and strain rate ranging from 7.8×10 - 4 s - 1? 1×10 - 2 s - 1. The test showed that maximum elongation of 367% can be achieved at 623 K and strain rate of 7.8×10 - 4 s - 1. The strain rate sensitivity (m) was evaluated by two different methods, uniaxial tensile test on the basis of the true stress true strain curve and by strain - rate jump test. The results show small differences between the two method) m = 0.42 - 0.45), which demonstrate that the grain boundary sliding (GBS) is the dominant deformation mechanism during superplastic test Keywords : Superplasticity. Severe plastic deformation. AZ31B magnesium alloy.

نظام ذكي لتقييم الخشونة السطحية لعملية تشكيل الصفائح التزايدية == Intelligent Surface Roughness Evaluation System of Ismf Process

اسم المؤلف: اوس خالد ابراهيم

اسم المشرف: وسام كاظم حمدان

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: تعد عملية تشكيل الصفائح التزايدية تقنية حديثة نسبيا لتشكيل الصفائح المعدنية والتي توفر امكانية تصنيع اجزاء معقدة الشكل وذلك باستخدام مكائن التفريز المبرمجة (CNC milling machines) بدون الحاجة الى قوالب خاصة لكل منتج والتي تتطلب وقتا طويلا للتصنيع مقارنة مع | Incremental Sheet Metal Forming (ISMF) is a modern sheet metal forming technology which offers the possibility of manufacturing 3D complex parts of thin sheet metals using the CNC milling machine. The surface quality is a very important aspect in any manufacturing process. Therefore, this study focuses on the surface quality of parts produced by single point incremental forming (SPIF) process. As a consequence, the objective of this study is to control the surface roughness by studying five forming factors, namely; (tool diameter, step size, tool shape, rotational speed and slope angle).In order to evaluate the surface quality, practical experiments for forming pyramid like shapes have been carried out on sheets of aluminum AA1050 with thickness 0.9 mm. As a result, two Adaptive Neuro - Fuzzy Inference systems (ANFISs) are conducted for predicting the surface roughness. The first system depends on the five forming factors as a direct contact estimation method while the second system utilizes contactless parameters (average gray level, standard deviation and mean frequency) that are extracted from the products images using a vision system as a contactless prediction method. A third model is developed using Sugeno Fuzzy Inference System (SFIS) for the evaluation of forming factors by which the surface roughness for a certain slope angle is obtained.Both quantitative and qualitative assessments have been used to explore the effects of the five forming factors on surface quality of parts produced by SPIF process. The ANOVA and MEP results show that the incremental step size and the forming tool shape are the most important factors affecting the surface roughness. These two factors are directly and inversely proportional to the surface roughness respectively. The maximum and minimum surface roughness, which is achieved from all the 24 experiments is (Ra = 4.3 & Ra = 0.18 µm) respectively. As a result, a surface with roughness smaller than the initial roughness of the sheet (0.27 µm) has been obtained. The qualitative assessment reveals that the surface roughness tends to increase towards the part deep.It can be concluded that the image based estimation of roughness using ANFIS is superior in terms of prediction accuracy. This vision system can achieve (97.856%) testing prediction accuracy compared to (85.799%) that is reached by the direct contact estimation of roughness. Conclusions also show that the vision system is capable of predicting the surface roughness of a hyperboloid part as a non - linear shape with prediction deviation (14.411%), thus enabling to evaluate the surface quality of complex parts that cannot be measured by the stylus. It can also be concluded that the SFIS is a successful approach for estimating the forming factors by which the surface roughness for a particular slope angle is obtained.

متغيرات اللحام المثلى بالقوس الكهربائي المغمور باستخدام طريقة تاكوشي == Optimizing of Submerged Arc Welding Parameters Using Taguchi Method

اسم المؤلف: هشام جواد كاظم

اسم المشرف: احمد علي اكبر اكبر

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: اللحام بالقوس الكهربائي المغمور غالبا مايستخدم في الصناعات الثقيلة. يستخدم في هذا النوع من اللحام سلك لحام مستمر يكون معدنن الملئ. االقوس يكون مغمور في مساعد الصهر والذي يتم تغذيته من خلال انبوب في حاوية اعلى سلك اللحام الذي يغذى باستمرار. مساعد الصهر يع | Submerged arc welding (SAW) is often used for heavy industries. The SAW process employs a continuous bare wire electrode that is consumed to produce filler, the arc is submerged in the flux, and the flux is supplied through a funnel located ahead of the filler wire which is fed continuously from a hopper, the flux contributes to deoxidize the base metal, and protect the molten weld metal from atmospheric contaminants In order to achieve best weld quality and good mechanical properties in manufacturing industries which need to be optimized. Selection of appropriate SAW parameters is essential to ensure a predictable weld bead which is important for obtaining high quality welding.Manufacturing industries and training centers often face the problem of selecting appropriate or optimum combinations of input welding parameters for achieving the required weld quality. Three input parameters of SAW were used to weld the steel plates, and four levels for each parameter, and three output response variables were used The experimental work consists of welding of sixteen low carbon steel plates of (AISI 1005) specimen measured 300 mm × 50 mm × 12 mm were submerged arc welded using welding currents (280, 340, 400, 460) amp, voltage (26, 29, 32, 35) volt and welding speeds (3.3, 5, 6.6, 8.3) mm/s This work details the application of Taguchi design to determine the optimal SAW parameters. An effort has been made to study the effect of SAW process parameters (current I, voltage V, speed S) on the bead geometry dimensions (depth of penetration P, bead width W, heat affected zone width w).Signal to noise ratios are computed to determine the optimum parameters. Statistical models have been developed based on multiply regression analysis relating the bead geometry with process parameters. The adequacy and significance of the models were checked by using ANOVA technique, also the models are validated using normal probability plot, and residual versus fit plots.The models were employed easily in form of executed program designed by using Visual Basic 6 software. The objective of such models and designed program is to predict weld bead geometry which enables selecting the desired weld parameters and select the weld bead dimensions. The effect of SAW parameters on heat affected zone and weld metal hardness also has been studied by means of hardness measurements, and grain size measurement using intercept method. Main and interaction effects of the process parameters on bead geometry are presented graphically. The experimental results were analyzed by using Minitab 16 software.It was found that current (280 to 460) amp causes increase in depth of penetration from (1.742 to 3.752) mm and HAZ width (1.222 to 1.512) mm. Bead width increases from (10.99 to 13.13) mm with increase in voltage from (26 to 35) volt and decreases from (12.61 - 11.80) mm with increase in welding speed from (3.3 to 8.3) mm/s. The welding speed and voltage do not affect appreciably the depth of penetration. Also change in weld speed reduces the width of the HAZ from (1.462 to 1.295) mm. The hardness of HAZ reaches maximum value 122.39 HV at the center of HAZ and decreases gradually toward the BM 109.22 HV; also it was found that the executed program is a useful tool used to predict weld bead geometry dimensions from welding parameters for SAW process.

التفريز المبرمج باستخدام ملفات STL == Cnc Milling Using Stl Files

اسم المؤلف: نادية سامي حسن

اسم المشرف: ليث عبد الله محمد

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: تعد ملفات (STL) من الملفات المهمة في برامج الرسم والتصميم المعان بالحاسوب (CAD) والشائعة الاستخدام حاليا في النمذجة السريعة وانظمة التصنيع المعان بالحاسوب (CAM). يتناول هذا البحث اقتراح وتطوير خوارزميات لقراءة ملفات (STL) واستخلاص السمات الهندسية اللازم | Stereolithography (STL) files are considered very important files in both computer aided drawing and design (CAD) programs and are commonly used now days in both rapid prototyping and computer aided manufacturing (CAM) systems.This thesis proposes and develops algorithms to read (STL) files and extract engineering entities required in CNC milling processes. The proposed algorithms are dependent on some mathematical modeling and manipulations of the engineering model by slicing an (STL) file to many slices and then building the required algorithms to adopt these slices to generate CNC machining paths as G - Code.The proposed system in this work is divided to three parts, in the first part of this thesis an algorithm is proposed to extract engineering object entities to some proposed models based on their (STL) files using Matlab program. The proposed models include cube, cylinder, dome, cone and cavity models. In the second part of this thesis, a slicing algorithm is proposed to enable the slices along the proposed models z - axis to find and navigate the required manufacturing data. UGS CAM program was used also to generate the tool paths and to simulate the machining process and then generate NC part program of the proposed objects (G - Code). The machining process was achieved using 3 - axis CNC milling machine, at spindle speed of (700 rpm) and feed rate (60 mm/min).Finally, the third part of this thesis includes comparing results produced based on both (STL) and (UGS), to achieve the required aim by experimentally comparing both objects surface roughness and evaluate their geometrical variations.According to the experimental results, the objects produced using STL models are clearly have rough surfaces compared with the surfaces produced by UGS with average percentage of 13µm, and according to the geometrical variations experiments, CAD readings are in good agreement with experimental results and confirm the validity of the proposed approach with 4.5mm of shape error.

دراسة مقارنة بين T - spline وNURBS في النمذجة والتشغيل باستخدام ماكنة التفريز المبرمجة == Comparison Study of T - Spline And NURBS In Modeling And Machining Using CNC Milling Machine

اسم المؤلف: مهند مصدق جعفر

اسم المشرف: ليث عبد الله محمد

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: نمذجة السطوح باستخدام تقنية الـ (T - spline ) تعد من اهم الوسائل المتسخدمة الان في التصميم المعان بالحاسوب (CAD).يهدف البحث الى زيادة الانتاجية من المنتجات المعقدة من خلال تعزيز عملية النمذجة السطحية للمنتج وتعزيز التصنيع باستخدام T - SPLINE للنمذجة السط | Surface modeling utilizing T - spline technique is one of the most important tool now in computer aided design (CAD).ThisThesisaims to increase the productivity of complicated products through enhancing the process of product surface modeling and manufacturing by using T - spline for surface modeling. This method provides the designer with many powerful tools to add details only where necessary on the CAD modeling, create non - rectangular topology of the surface, easily edit complex freeform models, and besides maintaining NURBS (non - uniform rational B - splines) compatibility of the model.ThisThesisuses T - spline for surface modeling and compare it with NURBS modeling to get the best modeling points between the two methods. The comparison will be through surface analysis and manufacturing process.ThisThesisincludes design of two types of models : convex model (bicycle seat) and concave model (longitudinal section of the bottle) for each T - spline surface and NURBS surface using Rhinoceros 5.0 software which has been transformed to UG - NX8.5 software to get the machining process simulation and G - code programs for the models. The models have been machined using 3 - axis vertical CNC machine (C - tek) type.Finally, analysis of surfaces (Environment Map analysis, Zebra analysis, Naked Edges analysis, Gaussian Curvature analysis, data structure analysis, Draft Angle analysis) by Rhinoceros 5.0 software and measurement of the roughness by Pocket Surf equipment and measurement runtime for machining by timer, shows that the T - Splines surfaces typically have (50 - 70%) less geometric data structure [ surfaces , 3d curve , 2d curves , vertices , edges , trims , loops , faces ] than the equivalent NURBS surface, inEnvironment Map analysis, the image of T - Spline surface for the models is reflected moreclearly than a NURBS surface, in Naked Edges analysis, the T - Spline surface for the models has a number of naked edge less than the NURBS surface, in measurement runtime for machining (roughing and finishing), the T - spline surface for the bicycle seat model is machined in (16 minutes) less than machining the NURBS surface, and the T - Spline surface for the longitudinal section of the bottle model is machined in (10 minutes) less than machining the NURBS surface. In measurement of roughness, the T - Spline surface for the bicycle seat model has (2.4861 µm) average (Ra) for patches measured roughness average (Ra), and the NURBS surface has (4.9216 µm) average (Ra) for patches measured roughness average (Ra).

تحليل مسار العدة في عملية التشكيل التزايدية للصفائح المعدنية == Analysis of Tool Path In Incremental Sheet Metal Forming Process

اسم المؤلف: ميثم سعد علي

اسم المشرف: وسام كاظم حمدان

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: التشكيل التزايدي للصفائح المعدنية هو عملية مرنة للغاية ومتعددة الاستعمالات للتصنيع السريع لاجزاء الصفائح المعدنيه المعقدة حيث تمتلك امكانية التكيف بامتياز مع انظمة التحكم الرقمي بالحاسوب (مكائن التفريز المبرمج CNC) من خلال السيطرة المباشرة على بيانات CAD | Incremental sheet forming (ISMF) is a highly versatile and flexible process for rapid manufacturing of complex sheet metal parts. It has excellent adaptability to computer numerical control (CNC) systems through direct control of CAD data, minimizing the use of specialized tooling and presses. A sheet of metal is formed by a progression of localized plastic deformation using simple forming tool controlled by a CNC machine - tool. The aim of the presented thesis is to investigate the feasibility of incrementally forming of 3D complex shape (like automotive heat shield shape) and the solar cooker shape by Single Point Incremental Forming process without using a dedicated die depending on different tool paths. Six different forming tool paths (unidirectional ZLVTP, bidirectional ZLVTP, FPRTP, ZGZTP, BSLTP and HSLTP) were generated byUnigraphics - NX8 (UGS - NX8) programing system and applied to realize solar cooker shape and automotive heat shield shape. The feasibility investigation and development of automotive heat shield shape is based on three control factors are tool path type, forming tool head shape and the Z - increment (vertical pitch). For each of these factors, levels were tested. The tool head shape and vertical pitch contain their both on two levels while the tool path type on six levels. Hence, 24 experiments applied to realize automotive heat shield shape based on a full factorial design of experiments, and 6 experiments applied to realize solar cooker shape. Hybrid tool paths are tested to explore the applicability these paths in ISMF process. This thesis discussed the impact of tool paths types and other control factors (tool shape and vertical pitch) on the three different quality characteristic namely geometrical accuracy, thickness variation and forming time. The significant of the control factors are explored using two statistical methods are analysis of variance ANOVA and main effect plot. All experiments were carried out on sheets of Aluminum Alloy (AL1070) with thickness 1.5 mm by using 3axis CNC machine. The CNC machine and dial gauge are used to measure dimensional accuracy and final thickness of formed parts respectively. Depending on the results of this work, Helical - Streamline tool path (HSLTP) and follow periphery tool path (FPRTP) are achieved higher geometrical accuracy when forming the solar cooker shape and the automotive heat shield shape respectively. On the other hand, Z Level profile tool path (ZLVTP) is the best tool path to achieve homogeneous thickness distribution and minimum forming time of formed parts. Hybrid tool paths are undesirable in incremental sheet metal forming. The ANOVA results show that all control factors have influence on the accuracy, especially the tool path type. The tool shape and vertical pitch have no influence on the thickness of the formed parts. But, the vertical pitch has major effects on the forming time and accuracy. In contrast, the tool path shape has a great influence on the process implementation.

التحقيق التجريبي والعددي للصفائح الرقيقة المثقوبة تحت الشد == Experimental And Numerical Investigations of Thin Tensioned Plates With Holes

اسم المؤلف: ارشد عبد الله راشد

اسم المشرف: كريم محسن يونس

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: ان الصفائح المثقوبة تستخدم عالميا في تصنيع الھياكل في التطبيقات الميكانيكية والانشاءات كمثال على ذلك ھياكل الطائرات والتراكيب الطبية ووصلات الربط الخ. ومن المعروف جيدا ان استعمال الثقوب في الھياكل المجھدة تولد اجھادا موقعيا عاليا في منطقة من الثقب تعرف بم | The plates with holes are used in cosmopolitan for manufacturing structures in mechanical and civil engineering applications like aircrafts, medical structures, joint connection applications etc. It is well known that utilizing holes in stressed structures produces highly localized stresses at area of the holes known as the stress concentration area,which leads to reduce the mechanical strength of the structures.The main objective of this study is to investigate the effect of three parameters on the stress concentration factor in plate with two holes having different size holes and subjected to uniaxial tension. The three parameters include firstly, the location of holes when oriented with respect to axis of loading, parallel, transverse and inclined with line of uniaxial tension load at different angles. Secondly, the aspect ratio for the hole size (large to small radius).The last parameter effect is the distance between two holes.Numerical simulation using finite element method for two - dimensional model is developed to determine the maximum value of Von Mises stress with commercial software package ANSYS V.11.The experimental photoelastic technique is carried out on fabricated polycarbonate model loaded in one direction. From the analysis of the results, it is found that the maximum stress concentration factor is at the point tangent to the edge of the hole. The comparison between the finite element method and experimental photoelastic technique results showed the stress concentration factor, which obtained experimentally and with finite element method are congruent, since the maximum variation between the two results is about 7.03% As well as the highest and lowest value of the stress concentration factor equal to 3.1973, 2.0640 at value of angle 60°, 90° respectively.It is recommended from the above conclusions that manipulating the three parameters which effect the stress concentration factor are namely, holes position, size, and distance between two holes on the plate that used in the application will play essential role to reduce the value of stress concentration factor which subsequently crucially minimize or avoid fast failure. This can be translated into saving precious lives preventing money wastage due to structures damage ending into catastrophe.

فحص بلى عدة القطع المعان بالرؤيا الحاسوبية خلال عملية الخراطة == Computer Vision Aided Inspection of Cutting Tool Wear In Turning

اسم المؤلف: علي كريم علوان العكيلي

اسم المشرف: علي عبار خليف

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: في الوقت الحاضر , تحظى مكائن القطع المبرمجة باھمية كبيرة في المعامل والورش التصنيعية بسبب دقتھا العالية ومرونتھا لكن لسوء الحظ لا تزال ھذه المكائن غير قادرة على التاكد من جودة السطوح المنتجة. الاتجاه نحو اتمتة عمليات القطع سير للحاجة الملحة للحصول على ج | Nowadays, computerized numerically controlled (CNC) machines have high importance in manufacturing factories and workshops due to their high accuracy and flexibility. Unfortunately they still cannot ensure the quality of machined products. The trend towards automation in machining has been driven by the need to maintain high product quality with improving production rate, these improvements can be possible by monitoring and control of machining process. In this research a vision based monitoringsystem was introduced for the on - line direct automated measurement of the cutting tool flank wear width based on a new algorithm on the basis of canny edge detection and morphological operations for the captured images.Twelve specimens were prepared using STARCHIP CNC turning with four cutting speeds (57,98,110 and 125 m/min) and three depths of cut (0.5,1 and 2 mm) and constant feed of (0.04 mm/rev). Maximum and minimum absolute error and error percentage in the maximum flank wear width was (0.058,0.002 mm) (9.7,0.54 %) respectively. The results show the effectiveness of the proposed method in the monitoring of the tool condition.Also, Vision based monitoring system was proposed for the measurement of tool nose wear which have direct interaction with the workpiece during machining. Measurement operation is done by comparing reference and worn tool images; the algorithm is composed of image preprocessing, Otsu thresholding, conforming method for the exact alignment between the two images and image subtraction is performed in order to detect the nose wear area. Morphological opening by reconstruction was used to remove isolated foreground pixels result in due to the quantization errors. The maximum and minimum error percentage in tool nose wear area (6.72,0.48 %) respectively; the experimental results show that nose wear occurs after the flank wear exceeded its maximum standard limit in roughing operations Keywords : tool wear, flank wear, nose wear image processing, automated visual inspection, tool condition monitoring.

دراسة سلوك البلى الانزلاقي الجاف لسبائك المنيوم - 7% سليكون عمليا وباستخدام تقنية تصميم التجارب == Studying Dry Sliding Wear Behavior of Al - 7% Si Alloys Using Experimental And DOE Techniques

اسم المؤلف: قاسم سعد عبد الواحد

اسم المشرف: عقيل ظاهر صبحي | علي عبار خليف

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: تعد سبائك الالمنيوم - سليكون والتي تحتوي على التيتانيوم احدى المواد التي تتميز بمقاومتها للبلى كما بينت الدراسات والابحاث العلمية ذلك.في هذا البحث تم صب سبيكة المنيوم - 7% سليكون وبنسب مختلفة من التيتانيوم (0.5 , 1 , 1.5%) وتحت معدلات تبريد مختلفة في قال | Aluminum - silicon alloys that contain Titanium can be considered one of the wear resistant materials and attract several researchers recently.In this work ,Al - 7%Si alloy with different percentages of Ti ( 0.5 , 1 , 1.5% ) was poured under different solidification conditions into the metal mould.All prepared alloys were dry slided under different bearing pressures ( 5 , 10 , 15 , 20 , 25 N ) on the steel counterface surface using pin on disk wear apparatus. Optical microscope and scanning electron microscope (SEM) were used to study the microstructure and determine wear mechanism of Al - Si alloys respectively. On the other hand , X - ray diffraction technique (XRD) was used to determine the phases that were present in the matrix of Al - Si alloys.Microstructural analysis and X - ray diffraction showed that two phases are presented in the matrix of Al - 7%Si alloys.These phases are ? - aluminum and eutectic and three phases are present in the matrix of Al - Si alloys that contains Ti. These phases are ? - aluminum ,eutectic and titanium aluminide Ti9Al23.Significant refinement occurred for ? - aluminum, eutectic and titanium aluminide Ti9Al23 phases when using metallic mould cooled with cold water in comparison with heated and unheated metallic moulds Hardness was increased with increasing Ti percentage and with increasing the severity of solidification condition used.Remarkable changes in the wear rate occurred for Al - Si alloys during dry sliding in which the magnitude of wear rate was dependent on the Ti percentage ,load and solidification condition used.Design of experiment (DOE) was used to optimize the effect of process variables ( load and Ti percentage) on the wear rate under different solidification conditions using computational statistical software (Mintab 16).

تاثير التشكيل على البنية المجهرية وسلوك البلى للمواد المعدنية المتراكبة النانوية Al2O3 / A356 == The Role of Forming On Microstructure And Wear Behavior of Metal Nano Composite Al2O3 / A356

اسم المؤلف: مروان باسل حسين

اسم المشرف: نوال عزت عبد اللطيف | عقيل ظاهر صبحي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: في هذا البحث تم تحضير المواد المركبة النانوية اساس معدني (A356/Al2O3) باستخدام تقنية (rheocasting) ومن ثم تم اجراء عملية التشويه على الساخن عند درجة حرارة °250 م.في البداية تم صهر السبيكة A356 في درجة حرارة °730 م بعدها تم تبريدها الى درجة حرارة الشبه ص | In the present work Al2O3/A356 nano composites have been prepared using rheocasting technique, the nano composites were then processed using hot deformation at 250 °C.Firstly A356 matrix alloy was melted at about 730 °C, the superheated molten alloy was allowed to cool to the semi - solid temperature at 600 °C, then Al2O3 nano - particles with different size (10,20) nm and different weight percentages (1 and 2)%wt were added inside the vortex formed due to stirring , hot deformation carried out with different ratio 30% and 40% at the temperatures of 250 °C and strain rates 0.1 s?1. The produced nano composites samples were characterized using optical and scanning electron microscopy ,X - ray diffraction , hardness test and wear test using pin on disc apparatus. The results of microstructural observations showed that the Al2O3 nano particles cluster mostly near the grain boundaries and form a band surrounding the grain boundaries. The dendritic structure of ? - Al phase is fragmented and the ? grains became more uniform and smaller than their corresponding as - cast 356 alloy. On other hand the microstructures of nano - Al2O3/A356 composites after casting and hot deformation at 250°C, showed modification of ? - Al and Si eutectic. The columnar dendrites ? - Al phase changed to the nearly equiaxed grains or globular morphology. The results of hardness test showed that the nano Al2O3/A356 composite were exhibited higher hardness than the as - cast A356 alloy The nano - composites hardness, increase with increases the size and increases in weight percentage of the Al2O3 nano - particles, and with increasing percentage deformation. The result of wear test showed that the hot deformed nano Al2O3 /A356 composites have greater wear resistance compared with hot deformed A356 alloy. Furthermore, with increasing the particle size and the percentage of Al2O3 nano particles, wear rate will decrease. The results also revealed that the optimal results was achieved at the nano - composites containing 20nm Al2O3 particles after hot deformation with 40%. SEM studies of the worn surface of nano composites showed that the main wear mechanism was oxidative in conjunction with metallic wear.

دراسة تاثير التوزيع الحجمي والشكل الحبيبي ومحتوى الفضة على خواص متراكبات النحاس - كرافيت المنتجة بطريقة ميتالورجيا المساحيق == Study The Effect of Particle Size And Shape And Silver Content on Properties of Copper - Graphite Composites Prepared By Powder Metallurgy Route

اسم المؤلف: عباس عبد الكريم حسين

اسم المشرف: فاروق منصور مهدي | رائد نجيب رزوقي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج والمعادن

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم هندسة الميكانيك

اللغة: العربية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

دراسة تاثير السباكة بالعصر وتقانة ميتالورجيا المساحيق على بعض خواص المواد المتراكبة ذات اساس المنيوم والمقواة بدقائق ZrO2 وY2O3 == Study The Effect of Squeeze Casting And Powder Metallurgy Technique on Some Properties of Aluminum Matrix Composites Reinforced With (ZrO2) And (Y2O3) Particles

اسم المؤلف: عبد القادر احمد عناز عثمان الجميلي

اسم المشرف: فاروق منصور مهدي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج والمعادن

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم هندسة الميكانيك

اللغة: العربية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

تحليل اساليب الادارة الهندسية وتطبيقاتها في صيانة محطة كهرباء بيجي الحرارية == Analysis of Engineering Management Methods And Its Application in Maintenance of Baiji Thermal Power Plant

اسم المؤلف: منصور حماد عبد العكيدي

اسم المشرف: سالم عبد الله صالح الدليمي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج والمعادن

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم هندسة الميكانيك

اللغة: العربية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

تاثير اضاقة الكرافيت على الخواص الميكانيكة و التشغيلية لسبيكة الالمنيوم برونز == Graphite Effects On Mechanical And Machining Properties Of Aluminum Bronze

اسم المؤلف: هالة حازم عبد الحق القيسي

اسم المشرف: حيدر عبد الحسن العذاري | علي هوبي حليم

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: جامعة بابل

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

استخدام مسيطر المنطق الضبابي للسيطرة على الدرفيل القائد في عملية درفلة الحلقات على البارد == Implementing Fuzzy Logic Controller For Guide Roll On Cold Ring Rolling

اسم المؤلف: مهند محمد حسين الخفاجي

اسم المشرف: جمال حسين محمد | جن ونليانغ

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة الانتاج

الدرجة: دكتوراه

الجامعة: الجامعة التكنولوجية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

سلوك الكلال التاكلي لسبيكة الالمنيوم 1100-H12 تحت تاثير القذف بالكريات بازمان مختلفة == Corrosion - Fatigue Behavior Of 1100 - H12 Al Alloy Under Different Shot Peening Times

اسم المؤلف: زينب عزيز بطي

اسم المشرف: حسين جاسم العلكاوي | عامر حميد مجيد

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المواد

الدرجة: ماجستير

الجامعة: الجامعة المستنصرية - كلية الهندسة

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

دراسة تاثير عوامل التشغيل الكيميائي للفولاذ المقاوم الصدا 420 == Studying The Influence Of Chemical Machining Parameters For Stainless Steel 420

اسم المؤلف: نسرين داخل فهد

اسم المشرف: حيدر عبد الحسن العذاري | كاظم فنطيل السلطاني

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

تـحضير الـولاســتونايت مــن مواد خام محـلية == Preparation Of Synthetic Wollastonite From Local Raw Materials

اسم المؤلف: محمد ميثم عبيد

اسم المشرف: ماجد محي شكر | الهام عبد المجيد ابراهيم

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: السيراميك

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم هندسة المواد

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

تحسين خصائص سمنت البورشايت الحياتي المحضر بواسطة دقائق نانوية من الهايدروكسي ابتايت == Improvement Of Prepared Brushite Biocement Properties By Hydroxyapatite Nanoparticles

اسم المؤلف: محمد ستار راضي نصيف الخفاجي

اسم المشرف: شاكر جاهل ادريس المحنا | عماد علي دشر الحيدري

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: السيراميك

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم هندسة المواد

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

المعالجة بالمزج الاحتكاكي لسبائك الالمنيوم من نوع 6061-T6 و 7075-T73 == Friction Stir Processing For 6061 - T6 And 7075 - T73 Aluminum Alloys

اسم المؤلف: علي عبد سلمان

اسم المشرف: كاظم كامل رسن | اياد مراد طخاخ

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المواد

الدرجة: ماجستير

الجامعة: الجامعة المستنصرية - كلية الهندسة

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

استخلاص ومزج الشيتوزان مع البولي مثيل ميثا اكريليت ودراسة خواصهم الفيزيوكيمياوية == Extraction And Blending Of Chitosan With Poly (Methyl Methacrylate) And Study Of Their Physiochemical Properties

اسم المؤلف: سرى فاهم عباس الخفاجي

اسم المشرف: جليل كريم احمد | زهير جبار عبد الامير

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: البوليمر

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم هندسة المواد

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

التاكل والسيطرة على التاكل في مصانع الاغذية == Corrosion And Corrosion Control In Food Industry

اسم المؤلف: سارة كريم نايف كاظم

اسم المشرف: عبد الواحد كاظم بكري | كاظم فنطيل السلطاني

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: هندسة المعادن

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

دراسة التصرف الريولوجي والميكانيكي والحراري لخليط البولي بروبلين مع مخلفات ما قبل الحقن باتجاه استخدامه لانتاج المحاقن الطبية == Study The Rheological, Mechanical And Thermal Behavior Of PP - Runner Waste Blends Towords Using For Medical Syringes Production

اسم المؤلف: زينب عبد الرحيم عبد الحسن السعدي

اسم المشرف: نجم عبد الامير سعيد | نزار جواد هادي

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: البوليمر

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم هندسة المواد

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

تحضير وتوصيف سيراميك الكورديرايت من الكاؤولين العراقي والمغنسايت == Preparation And Characterazation Of Cordierite Ceramic From Iraqi Kaolin And Magnesite

اسم المؤلف: زينب جواد كاظم

اسم المشرف: محسن عباس اسود | ماجد محي شكر

الموضوع العام: هندسة الانتاج والمعادن والمواد

السنة: 2014

الموضوع الدقيق: السيراميك

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم هندسة المواد

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى: