Main Subjects : Production & Metallurgy
Neam F. Mohammed; Bahaa S. Mahdi; Amin D. Thamir
Hydrogen embrittlement is a diffusible Hydrogen that is harmful to the toughness of iron. It follows, therefore, that the harmful influence of diffusible Hydrogen can be mitigated by preventing its entry into steel. This approach was achieved by usingthree coating layersas a coating nanostructure thin layer by DC sputtering on steel structural (AISI l018) and hydrogen charging (HC) effect on uncoated and different Nano coated tensile specimens. The first layer was Titanium as a bonding layer, the second layer was TiO
2 with Al
2O
3, and the third layer was Al
2O
3. Using a titanium Nano layer coating on AISI1018 steel tensile specimens increased the tensile strength from 570 to 659 MPa with 16 hours of charging, which is considered a good increase. In contrast, the elongation remained in a steady-state with little difference in values compared to changing the charging time and the coating of the double layer. Furthermore, it was found that samples coated with TiO
2 and Al
2O
3 by the DC method had advanced hydrogen embrittlement resistance and increased tensile strength (from 565 to 680 MPa with 8 hours of charging process). Moreover, the maximum adhesion value was related to the triple layer at 596 psi, and the lowest value was 309 psi using the titanium layer alone. The coating time was 5 hours of the sputtering process for all specimens. Thecoating layers are considered a good barrier for hydrogen permeation through steel structures (AISI 1018).
Ayat Sabah; Luma A.H. Al-Kindi; Zainab Al-Baldawi
The main challenge facing industrial companies is how to stay competitive in a fast changing world. They should adopt an effective supply chain that enables them to deliver products in a short period of time. This forced organization to change their pattern of processing and become lean. Lean manufacturing system is the best philosophy to achieve the objectives of the industrial organizations and to reduce the waste activities. The unnecessary movement, defective, waiting, inadequate processing, unnecessary inventory, excessive transport, overproduction, and the underutilization of people and facilities are the most types of waste found in the industries. Many industries have experienced the benefits of applying the lean concept in their area to improve the production processes, resources utilization, reduce production lead time, and eliminate wastes in the activities which is the goal of lean concept in the manufacturing industry. In this research, the lean concepts are presented in the leather shoes manufacturing industry in the city of Baghdad, it aimed to decrease the lead time of production, minimize the non-value time, and improve the production line. By using the most essential lean tool, value stream mapping, where the current and future map capture the flow of material and information of the production line before and after the implementation of the proposed improvement. The hybrid push/pull strategies and Kanban production were implemented to improve the production line. After adopting the suggested improvement, the production lead time reduced from 130.6 to 14.8 hours and the non-value added reduced from 118 to 10.8 minutes.
Momena M. Mohammed; Mohanned M. H. AL-Khafaji; Tahseen F. Abbas
The main contribution of this paper is to develop an innovative algorithm to accurately detect and identify the shape and color of objects under various light intensities and find their location to be manipulated by a pick-and-place robotic arm. Workpieces of various shapes and colors are dispersed on the robot's work plane and manipulated according to its specifications. The proposed algorithm utilizes the HSV color model to distinguish between different object colors and shapes. The S channel is used to detect the shapes of objects. After that, a series of filters (Median, Bilateral, and Gaussian) are applied to reduce the noise of the segmented image to make the process of discovering the shape and coordinates of the objects successful. The draw-contour method is used to discover the object’s shapes. After the shape of the object is discovered, the centroid coordinates are calculated. After extensive testing on 354 images that are captured in various lighting conditions in the range of (5-7000 lux), the overall system performance of 93.83% is achieved, and the average execution time is 2.21s. Finally, we had a dependable flexible automatic pick and place system that could correctly detect and identify the objects based on their features.
Tahseen F. Abaas; Alaa H. Shabeeb
In the mobile robot workplace, the path planning problem is crucial. Robotic systems employ intelligence algorithms to plan the robot's path from one point to another. This paper proposes the fastest and optimal path planning of the wheeled mobile robot with collision avoidance to find the optimal route during wheeled mobile robot navigation from the start point to the target point. It is done using a modern meta-heuristic hybrid algorithm called IPSOGWO by combining Improved Particle Swarm Optimization (IPSO) with Grey Wolf Optimizer (GWO). The principal idea is based on boosting the ability to exploit in PSO with the exploration ability in GWO to the better-automated alignment between local and global search capabilities towards a targeted, optimized solution. The proposed hybrid algorithm tackles two objectives: the protection of the path and the length of the path. During, Simulation tests of the route planning by the hybrid algorithm are compared with individual results PSO, IPSO, and GWO concepts about the minimum length of the path, execution time, and the minimum number of iterations required to achieve the best route. This work's effective proposed navigation algorithm was evaluated in a MATLAB environment. The simulation results indicated that the developed algorithm reduced the average path length and the average computation time, less than PSO by (1%, 1.7%), less than GWO by (1%, 1.9%), and less than IPSO by (0.05%, 0.4%), respectively. Furthermore, the superiority of the proposed algorithm was proved through comparisons with other famous path planning algorithms with different static environments.
Zainab Z. Ali; Baha S. Mahdi; Ameen D. Thamer
This work studies the protection from corrosion in the inner surface of petroleum storage tanks by applying nano-coating on the AISI1018 steel type used in these tanks. BNi-2 alloy, used as coating layer, was deposited using the DC sputtering technique to obtain protection layers of nano-coating. The cyclic potential dynamic polarization technique is used to study and evaluate the resistant metal to localize corrosion, for example, pitting and crevice corrosion. The samples were evaluated in a 3.5% NaCl aqueous solution using the polarization method to determine the corrosion rate. The input parameters of deposition included ion current 16 mA, vacuum 10
-1 mbar, time of deposition was 60 minutes, and the distance between target and substrate was 2.5 cm. The surface roughness of the uncoated specimens was (0.1466 µm), and after coating, it decreased to (0.0933µm). The most important factor that affects the corrosion of the coated steel surface is the surface topography of steel before coating, as it is known that the spattering process coats the facing surface to target better than the inclined surface topography. Therefore, some micro scratches non-coated well worked as nucleation for corrosion as detected in stereo microscope images for coated and uncoated surfaces. By calculating the corrosion rate from cyclic potential dynamic polarization for coated and uncoated workpieces, pitting and crevice corrosion improved approximately ten times compared to the uncoated AISI1018 steel surface.
Ahmed M. Marheb; Akeel D. Subhi
In this work, the cyclic expansion extrusion (CEE) process was applied to ZK60 Mg alloy. The correlation between the evolved microstructure and mechanical properties was investigated. The CEE process was performed at a constant ram speed (15 mm/min) and at different processing temperatures (190, 270, and 350
°C). Optical and scanning electron microscopes, X-ray diffraction instruments, Vickers hardness tester, and tensile testing machine were utilized to examine the influence of CEE processing temperature on the characteristics of ZK60 Mg alloy. The XRD analysis showed that two phases were presented in the matrix of ZK60 Mg alloy, namely α-Mg and MgZn
2, in small amounts. The CEE process reduced the size of α-Mg grains due to dynamic recrystallization, especially at the processing temperature of 190
°C. A slight coarsening of the α-Mg grains was observed with increasing processing temperature to 270 and 350
°C. The hardness value of ZK60 Mg alloy was enhanced by about 11 to 19% using the CEE process compared to the as-extruded sample. The processing temperature greatly affected the mechanical properties, where a significant improvement of about 24% yield strength, 9% ultimate tensile strength, and 38% elongation was observed using a processing temperature of 190
°C. The characterization of the tensile fracture surface of the tested samples indicated that the ductile-brittle fracture mode was responsible for the failure.
Mustafa M. Hadi; Mohanned M.H. AL-Khafaji; Akeel D. Subhi
A full-dimensions 3-D numerical model based on the Lagrangian approach has been employed to predict the peak temperature and the plastic strain distribution in the FSW of (AA5754) joints using ABAQUS software. The material’s model utilizes the classical plasticity model in addition to defining the thermophysical properties of the alloy using JMatPro software to increase the accuracy of the numerical results. The basic variables of FSW were three rotational speeds (930, 1460, and 1860 rpm) and three traverse speeds (35, 65, and 95 mm/min). The influence of the rotational and traverse speed on temperature profile and plastic strain has been studied. The simulation results showed that increasing the rotational speed led to increasing the peak temperature, which concentrated under the tool’s bottom surface while increasing the traverse speed decreased the peak temperature recorded. The highest peak temperature was (497
oC) at a rotational speed of (1860 rpm) and a traverse speed of (35 mm/min). It was also found that the rotational speed increased the plastic strain starting from the tool’s neck and continuing along the pins’ position and gradually decreasing towards the bottom. In addition, a V-shape pattern has appeared in the temperature distribution across the workpiece’s cross-section, representing the heat loss during the FSW by the backplate due to heat conductance.
Maria F. Jasim; Tahseen F. Abbas; Abdullah F. Huayier
Fused deposition modeling (FDM) is an additive manufacturing (AM) process often used to build geometrically complex prototypes and parts. It is becoming more popular since it improves products by eliminating the need for high-priced equipment. Materials, printing methods, and printing variables all impact the mechanical characteristics of printed items. The process parameters of FDM affect the parts' quality and functionality. This study examines the influence of different infill patterns on test specimens made of polylactic acid (PLA) tensile strength. Total of 10 different infill patterns (IPs): Grid, Lines, Triangles, Tri-Hexagon, Cubic, Gyroid, Zig-zag, Concentric, Octet, and Cubic subdivision were taken as process variables. Samples were printed using processing parameters (speed 60 mm/s, layer height 0.1 mm, infill density 80%, extruded at 200◦C). The ASTM D638 tensile test was used to determine the tensile strength based on this printing parameter. According to tensile test results, the infill pattern significantly affects the tensile strength. The results showed that the concentric infill pattern has a higher tensile strength of 32.174 MPa, whereas the triangles infill pattern has a lower tensile strength of 20.934 MPa.
Zaman A. Abdulwahab; Sami I. Jafar; Sami A. Ajeel
The present paper investigates the nanomaterial coatings effect on turbine blades by laser processing. The present paper explores the impact of laser cladding parameters on the corrosion behavior of the resulting surface. Powders of Inconel 600 were deposited on the steel substrate. The surface can be thought of as the most important part of every engineering component. Unlike the rest of the component's volume, the surface is exposed to wear and becomes the place where most cracks form and corrosion initiates. Corrosion is one of the most harmful problems affecting turbine blades. In the current investigation, coating nanomaterials, namely Inconel 600, have been used to resist corrosion. The specimens of tests have been obtained from the part of the turbine blades in Al-Doura Station, located south of Baghdad. These specimens are separated into two groups: The 1st group is received specimens, and the 2nd group is with nanoparticle coating, including Inconel 600 coating applied by laser cladding. The procedure of cladding was implemented utilizing the following parameters :(11 j) pulse energy, (6 Ms.) pulse width, (12 Hz) pulse frequency, (132 W) laser average power, and (1.83 KW) laser peak power. The results show that the microstructure of steels after laser processing is greatly refined with equiaxed grains and highly homogeneous as compared with those of steels before laser treatment, resulting in a significant improvement in strength, toughness, and fatigue corrosion.
Asma A. Mohammed Ali; AllaEldin H. Kassam
Choosing a suitable supplier of materials and equipment in the healthcare sector is essential because it directly affects the patient's health and the organization's effectiveness and quality of services. Moreover, studies on supplier ranking are few in the field of health, particularly in the dental sector. For this purpose, an integrated fuzzy (AHP-TOPSIS) model has been developed for supplier ranking in the dental sector. The F-AHP is used to evaluate the importance of criteria, and then the F-TOPSIS method is applied to the supplier ranking process. A real case study is conducted on dental composite filling suppliers. Six evaluation criteria are identified, and five potential suppliers are selected through a direct interview with a group of experts. Then a questionnaire is applied to 12 experts (dentists) to rate the importance of evaluation criteria and to evaluate suppliers based on evaluation criteria. Evaluating the importance of criteria using F-AHP indicated that quality is the most important criterion. It has a weight of 0.22, followed by esthetic and durability with a weight of 0.21 for both. Moreover, the result of ranking using F-TOPSIS indicated that supplier A5 is the top supplier with a value of (0.532).
Abdul Jabbar S. Jomah; Akeel D. Subhi; Fadhil A. Hashim A. Hashim
The welding process is one of the fabrication processes in which tubes can be performed for structural purposes and transport liquids or gases. This study is focused on the manufacturing, characterization, and evaluation of mechanical properties of welded tubes made from oxygen-free copper (C1020) sheets using friction crush welding. The welded tubes were produced using different tool rotation speeds (1500, 1600, and 1700 rpm) and feed rates (130, 140, and 150 mm/min). The flanged edge height of 2.5 mm and 0.5 mm gap between the ends of the copper sheet was used. All examinations on welded tubes were achieved using different instruments such as optical microscopy, SEM, hardness, and tensile testers. The microstructure study showed good weld quality and good material flow between the two ends of the copper sheet in the weld zone. Moreover, the weld zone was not defective. The lowest hardness was identified in the crush zone due to the coarseness of the copper grains. The highest tensile strength of 105 MPa was obtained at the tool rotation speed of 1500 rpm and 130 mm/min feed rate. The results also showed that ductile fracture is the main source of failure.
Farhan K. Challab; Maan A. Tawfiq; Salah K. Jawad
The present work studies three variables (cutting velocity, feed rate, and cut depth) on hard turning cutting temperature of uncoated and multilayer-coated carbide (TiN, TiN/TiCN, TiN /Al2O3/ TiCN) inserts are used in AISI 1045 alloy steel. The tool's temperature was measured simultaneously, measuring the temperature of the tool-chip interface using infrared radiation (IR) pyrometer in this investigation. This study investigated the performance of four distinct coated and uncoated PVD and CVD tools during turning operations. Four cutting speeds (56, 88, 112, 141) m/min, four feed rates (0.065, 0.08, 0.16, 0.228) mm/rev., in the experiments, a constant cutting depth of (1) mm was used. The results also show that Coarse cutting tools have a lower tool temperature than uncoated ones. In comparison to uncoated and other coated tools, the three-layer (TiN/ Al2O3/ TiCN) coating is especially effective in a range of (32% to 39%) than uncoated inserts at various cutting velocity and constant feed rates, with varying feed rates and consistent cutting velocity and lower by approximately( 34% to 40%) than uncoated inserts.
Shukry H. Aghdeab; Anwer Q. Abdulnabi
Electrical Discharge Machining process (EDM) is a nontraditional metal removal technique that uses thermal energy to erode the workpiece without generating any physical forces of cutting between the tool and the machining part. It is used to cutting of hard and electrical conductivity materials and product intricate shapes of products. The aim of this work is to study the effect of changing voltage values on electrode wear rate (EWR). The machining parameters includes voltage (V), peak current (Ip), pulse duration (Ton) and finally, pulse interval (Toff). The results show that the EWR was increase with rising in voltage, peak current and pulse duration values but when the pulse interval value rises, the electrode wear rate reduce. The best (EWR) value was (0.093507) mm3/min that obtained at voltage (140) V, Ip (12) A, Ton (400) µs and Toff (12) µs.
Adnan I. Mohammeda; Ibrahim K. Ahmed; Munir A. Allow
The mechanical components are produced by various fabrication methods, although forged products have excellent mechanical characteristics at a minimal cost. The stress and temperature analysis process in the closed die hot forging contributed to finding failure regions in these dies through simulations in the FE program. This enables the process to be improved and reduced time and mineral losses. A simplified model was used to represent the forming process, with a temperature of (1150-950 °C) was simulated using MSC Simufact software. The forge fastener head product is formed with a horizontal mechanical press of 800 tones. In this research, the workpiece material used Ck45 alloy steel, 56NiCrMoV 7 tool material. The results illustrate the maximum equivalent stresses values, and the maximum value was 739.70 MPa / 240.64 on lower die and product at a heating temperature of 950 °C, respectively. The local plastic deformation would be expected at places where the maximum stress is generated and exceeds the yield strength of the die material.
Naeem A. Abdulhusein; Abbas F. Ibrahim; Abdullah F. Huayier
This study discussed the influence of chemical machining parameters such as (machining time, type of etchant, etching temperature, and concentration of the solution) on the surface roughness of ceramic material (silicon carbide) as a workpiece in the chemical machining (CHM) process. To achieve the best value for surface roughness. In this research, four levels of factors affecting the chemical etching process were used, the values of etching temperature (60, 80, 100, and 120) °C, the etchant concentration (50, 60, 70, and 80) %, and machining time (30, 50, 70, and 90) min, and two etchant type (HBr, HCl). Experiments proved the best value of surface roughness is obtained (2.933) µm experimentally and (2.958) µm at a predictable program when using hydrochloric acid (HCl) at a temperature (80) °C, time (50) min, and etchant concentration (50) %. The coefficient determination (R-sq) to predict the surface roughness is ((93.7).
Ameer J. Nader; Saad K. Shather
Abrasive water jet (AWJ) is one of the most advanced and valuable non-traditional machining processes because of its massive advantages of removing metal from hard and soft metals. This paper has studied the effect of jet pressure, feed rate, and standoff distance on material removal rate throughout abrasive water jet cutting of carbon steel metal workpieces. The material removal rate was assessed using a precision balance device by performing sixteen experiments to identify the ratio of weight loss to total cutting time. The Taguchi method was introduced to implement the experiments and indicate the most influential process parameters on material removal rate. The experimental results showed that feed rate and pressure jet had the most effect on material removal rate. The best material removal rate value was 3.71 g/min at jet pressure 300 MPa, feed rate 30 mm/min, and standoff distance 4mm.
