AHMED SAMIR ANWAR ALEMDAR | Salahaddin University-Erbil (original) (raw)
Papers by AHMED SAMIR ANWAR ALEMDAR
Heliyon
The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However,... more The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However, it has come under scrutiny due to its high cost. This study aims to decrease the cost of manufacturing through a hybrid design that uses AA2198-T8 alloys for the crucial parts and AA2024-T3 alloys for the remaining structure. The two main techniques for joining AA2024-T3 to AA2198-T8 are reversed double-sided friction stir welding (DS-FSW) and traditional single-sided friction welding (SS-FSW). They were carried out under unaltered tool rotation speed followed by five different welding speeds. The mechanical properties of the joints were explored, and the maximum joining efficiency of the welding process was 96% for reversed DS-FSW at 102 mm/min welding speed. The hybrid joint was tested for compliance with ASTM G34 standards to examine the welding joint's exfoliation corrosion (EXCO) for eight exposure times. The findings showed that joint efficiency decreased relative to as-welded joints, and mechanical property deterioration increased with EXCO exposure duration, reaching 40% for specimens exposed for 120 h to the corroding solution. It has been noted that morphology and grain size changes significantly impact EXCO.
ZANCO JOURNAL OF PURE AND APPLIED SCIENCES, 2018
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc. by introducing residual compressive stress into the surface of the work piece. In this study five pass of burnishing process was applied to machined 15 mm diameter AISI 316L austenitic stainless steel in five different depth of burnishing (0.1, 0.2, 0.3, 0.4 and 0.5 mm), burnishing time was one minute and spindle speed were 1050 rpm and 1800 rpm. Surface roughness of burnishing surface was detected. At low spindle speed 1050 rpm the lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L in fifth pass and depth of burnishing equal to 0.5 mm. While at higher spindle speed the best surface finish can be obtained during burnishing AISI 316L austenitic stainless steel in fourth pass and depth of burnishing equal to 0.4 mm.
International Journal of Mechanical and Production Engineering Research and Development, 2019
The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for ... more The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for oil works in KAR storage tanks. In this study we have found out the chemical and physical changes of the welded steel plate after the damage happened due to the ISIS attack in Bai-Hassan in Kirkuk. After receiving the samples of burned and heated steel plates, it has been machined the samples for tensile, hardness, chemical analysis and microstructural analysis. The plate thickness is reduced in certain areas of the plate due to oxidation at high temperatures of the material occurred especially at the weld area and the thickness of the plate is found to be between 13 and 18 mm. Due to the coarsening of the microstructure and the development of Widmanstatten ferrite which is a weak and undesirable microstructure has been seen in the microstructure of this steel. Extraction of Acoustic Emission (AE) signal features (magnitude, power, hit, time period and rise period varies with time and the relation between them) will use for identifying the corrosion level and diagnosing the type of corrosion of the steel plates of oil storage tank, and moreover to measure the corrosion severity of the complete storage tank.
Metals, 2017
In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite E... more In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite Element Model (FEM). The temperature distribution, microstructure, grain growth, and the hardness of the heat-affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close agreement between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheat temperature on the martensite formation is analysed, and it is shown that 225 • C preheating completely eliminates the martensite formations for the 12 mm thick plate.
Steel corrosion, 2019
The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for ... more The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for oil works in KAR storage tanks. In this study we have found out the chemical and physical changes of the welded steel plate after the damage happened due to the ISIS attack in Bai-Hassan in Kirkuk. After receiving the samples of burned and heated steel plates, it has been machined the samples for tensile, hardness, chemical analysis and microstructural analysis. The plate thickness is reduced in certain areas of the plate due to oxidation at high temperatures of the material occurred especially at the weld area and the thickness of the plate is found to be between 13 and 18 mm. Due to the coarsening of the microstructure and the development of Widmanstatten ferrite which is a weak and undesirable microstructure has been seen in the microstructure of this steel. Extraction of Acoustic Emission (AE) signal features (magnitude, power, hit, time period and rise period varies with time and the relation between them) will use for identifying the corrosion level and diagnosing the type of corrosion of the steel plates of oil storage tank, and moreover to measure the corrosion severity of the complete storage tank.
Welding, 2017
In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite E... more In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite Element Model (FEM). The temperature distribution, microstructure, grain growth, and the hardness of the heat-affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close agreement between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheat temperature on the martensite formation is analysed, and it is shown that 225 • C preheating completely eliminates the martensite formations for the 12 mm thick plate.
Burnishing cold working process, 2015
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc by introducing residual compressive stress into the surface of the work piece. In this study burnishing process was applied to machined AISI 316L austenitic stainless steel at two different spindle speed 560rpm and 1030 rpm, with five different depth of burnishing (0.04, 0.08, 0.12, 0.16 and 0.2mm) for two different burnishing time 30 sec. and 60 sec. Surface roughness of burnishing surface in addition of reduction in spindle diameter were detected. The lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L with lower spindle speed 560rpm, depth of burnishing equals 0.2mm and 60 second burnishing time.
Super duplex stainless steel SAF 2507, 2015
The purpose of this paper is to study the effect of heat treatment on sliding wear property of su... more The purpose of this paper is to study the effect of heat treatment on sliding wear property of super duplex stainless steel SAF 2507.Sliding wear volume determined as a function of aging temperature. Four different aging temperatures were selected 700C, 800C, 900C, and 1000C .The specimens remained at these temperatures for 60 minutes and then quenched in water. During aging super duplex stainless steel SAF 2507 various transformations at microstructure will induced involving precipitation of chromium carbides and nitrides, sigma (σ) phase and other intermetalic phases which influence the wear property. The specimens aged at (800C) exhibit highest wear resistance.
Burnishing process, 2018
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc. by introducing residual compressive stress into the surface of the work piece. In this study five pass of burnishing process was applied to machined 15 mm diameter AISI 316L austenitic stainless steel in five different depth of burnishing (0.1, 0.2, 0.3, 0.4 and 0.5 mm), burnishing time was one minute and spindle speed were 1050 rpm and 1800 rpm. Surface roughness of burnishing surface was detected. At low spindle speed 1050 rpm the lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L in fifth pass and depth of burnishing equal to 0.5 mm. While at higher spindle speed the best surface finish can be obtained during burnishing AISI 316L austenitic stainless steel in fourth pass and depth of burnishing equal to 0.4 mm.
Heliyon, 2023
The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However,... more The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However, it has come under scrutiny due to its high cost. This study aims to decrease the cost of manufacturing through a hybrid design that uses AA2198-T8 alloys for the crucial parts and AA2024-T3 alloys for the remaining structure. The two main techniques for joining AA2024-T3 to AA2198-T8 are reversed double-sided friction stir welding (DS-FSW) and traditional single-sided friction welding (SS-FSW). They were carried out under unaltered tool rotation speed followed by five different welding speeds. The mechanical properties of the joints were explored, and the maximum joining efficiency of the welding process was 96% for reversed DS-FSW at 102 mm/min welding speed. The hybrid joint was tested for compliance with ASTM G34 standards to examine the welding joint's exfoliation corrosion (EXCO) for eight exposure times. The findings showed that joint efficiency decreased relative to as-welded joints, and mechanical property deterioration increased with EXCO exposure duration, reaching 40% for specimens exposed for 120 h to the corroding solution. It has been noted that morphology and grain size changes significantly impact EXCO.
Advances in Materials Science and Engineering
The study presents the hybrid joining of the third generation AA2198-T8 aluminum lithium alloy to... more The study presents the hybrid joining of the third generation AA2198-T8 aluminum lithium alloy to AA2024-T3 aluminum copper alloy, which has been highly demanded recently in the aerospace industry. This investigation aims to reduce the cost of production in the industrial sector. As a result, an affordable alternative is to use hybrid designs using AA2198-T8 alloy in crucial parts and AA2024-T3 alloy in the rest of the structure. A joining method is required to create hybrid structures composed of last-generation and standard aluminum alloys. The joining process was successfully friction stir-welded using five different welding travel speeds—36, 76, 102, 146, and 216 mm/min—with an invariable spindle speed of 960 rev/min. Two reversed steps, double-sided friction stir welding (DS-FSW) and single-sided friction stir welding (SS-FSW) techniques with two appropriate tool designs, were employed to investigate the dissimilar material mechanical properties and their morphological changes....
Materials Research Express, 2019
In the brake friction composites (BFCs), fibres take part in significant attention as reinforceme... more In the brake friction composites (BFCs), fibres take part in significant attention as reinforcement in governing mechanical and thermal-mechanical properties. The current investigation aims to develop hybrid brake friction composites using recycled basalt-aramid fibre integration and to characterise for its mechanical and thermal properties. The experiments related to thermal (heat swell, loss of ignition and thermal conductivity) and mechanical (tensile, compression, flexural and impact) properties were conducted as per industrial standards. From the experimental investigations, it was concluded that fibre inclusion in the BFCs enhanced the mechanical and thermal properties considerably. Further, with the aid of scanning electron microscope (SEM), fracture interfaces of the tested friction composites were analyzed for various characteristics like pullout, void, fibre-matrix bonding etc.
Thesis Chapters by AHMED SAMIR ANWAR ALEMDAR
MSc Thesis, 2013
In the present study, arc welding of the AISI 1045 steel is modelled by using 2D-FEM for three ty... more In the present study, arc welding of the AISI 1045 steel is modelled by using 2D-FEM for three types of welding groove; V, double V and U. The temperature distribution, microstructure, grain growth, and the hardness of the heat affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close value between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheating temperature
on the martensite formation is analysed. It is shown that 225oC, 300oC and 350oC preheatings
eliminate completely the martensite formation for 12 mm thick, V, U and
double V-shaped butt welding of AISI 1045 steel. Among the welding grooves, the Vshape
is providing the lowest martensite formation and the lowest preheating
temperature for martensite elimination.
Heliyon
The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However,... more The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However, it has come under scrutiny due to its high cost. This study aims to decrease the cost of manufacturing through a hybrid design that uses AA2198-T8 alloys for the crucial parts and AA2024-T3 alloys for the remaining structure. The two main techniques for joining AA2024-T3 to AA2198-T8 are reversed double-sided friction stir welding (DS-FSW) and traditional single-sided friction welding (SS-FSW). They were carried out under unaltered tool rotation speed followed by five different welding speeds. The mechanical properties of the joints were explored, and the maximum joining efficiency of the welding process was 96% for reversed DS-FSW at 102 mm/min welding speed. The hybrid joint was tested for compliance with ASTM G34 standards to examine the welding joint's exfoliation corrosion (EXCO) for eight exposure times. The findings showed that joint efficiency decreased relative to as-welded joints, and mechanical property deterioration increased with EXCO exposure duration, reaching 40% for specimens exposed for 120 h to the corroding solution. It has been noted that morphology and grain size changes significantly impact EXCO.
ZANCO JOURNAL OF PURE AND APPLIED SCIENCES, 2018
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc. by introducing residual compressive stress into the surface of the work piece. In this study five pass of burnishing process was applied to machined 15 mm diameter AISI 316L austenitic stainless steel in five different depth of burnishing (0.1, 0.2, 0.3, 0.4 and 0.5 mm), burnishing time was one minute and spindle speed were 1050 rpm and 1800 rpm. Surface roughness of burnishing surface was detected. At low spindle speed 1050 rpm the lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L in fifth pass and depth of burnishing equal to 0.5 mm. While at higher spindle speed the best surface finish can be obtained during burnishing AISI 316L austenitic stainless steel in fourth pass and depth of burnishing equal to 0.4 mm.
International Journal of Mechanical and Production Engineering Research and Development, 2019
The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for ... more The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for oil works in KAR storage tanks. In this study we have found out the chemical and physical changes of the welded steel plate after the damage happened due to the ISIS attack in Bai-Hassan in Kirkuk. After receiving the samples of burned and heated steel plates, it has been machined the samples for tensile, hardness, chemical analysis and microstructural analysis. The plate thickness is reduced in certain areas of the plate due to oxidation at high temperatures of the material occurred especially at the weld area and the thickness of the plate is found to be between 13 and 18 mm. Due to the coarsening of the microstructure and the development of Widmanstatten ferrite which is a weak and undesirable microstructure has been seen in the microstructure of this steel. Extraction of Acoustic Emission (AE) signal features (magnitude, power, hit, time period and rise period varies with time and the relation between them) will use for identifying the corrosion level and diagnosing the type of corrosion of the steel plates of oil storage tank, and moreover to measure the corrosion severity of the complete storage tank.
Metals, 2017
In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite E... more In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite Element Model (FEM). The temperature distribution, microstructure, grain growth, and the hardness of the heat-affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close agreement between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheat temperature on the martensite formation is analysed, and it is shown that 225 • C preheating completely eliminates the martensite formations for the 12 mm thick plate.
Steel corrosion, 2019
The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for ... more The steel plate Grade S355GT st52 of KAR Group is used for the construction of storage tanks for oil works in KAR storage tanks. In this study we have found out the chemical and physical changes of the welded steel plate after the damage happened due to the ISIS attack in Bai-Hassan in Kirkuk. After receiving the samples of burned and heated steel plates, it has been machined the samples for tensile, hardness, chemical analysis and microstructural analysis. The plate thickness is reduced in certain areas of the plate due to oxidation at high temperatures of the material occurred especially at the weld area and the thickness of the plate is found to be between 13 and 18 mm. Due to the coarsening of the microstructure and the development of Widmanstatten ferrite which is a weak and undesirable microstructure has been seen in the microstructure of this steel. Extraction of Acoustic Emission (AE) signal features (magnitude, power, hit, time period and rise period varies with time and the relation between them) will use for identifying the corrosion level and diagnosing the type of corrosion of the steel plates of oil storage tank, and moreover to measure the corrosion severity of the complete storage tank.
Welding, 2017
In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite E... more In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite Element Model (FEM). The temperature distribution, microstructure, grain growth, and the hardness of the heat-affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close agreement between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheat temperature on the martensite formation is analysed, and it is shown that 225 • C preheating completely eliminates the martensite formations for the 12 mm thick plate.
Burnishing cold working process, 2015
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc by introducing residual compressive stress into the surface of the work piece. In this study burnishing process was applied to machined AISI 316L austenitic stainless steel at two different spindle speed 560rpm and 1030 rpm, with five different depth of burnishing (0.04, 0.08, 0.12, 0.16 and 0.2mm) for two different burnishing time 30 sec. and 60 sec. Surface roughness of burnishing surface in addition of reduction in spindle diameter were detected. The lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L with lower spindle speed 560rpm, depth of burnishing equals 0.2mm and 60 second burnishing time.
Super duplex stainless steel SAF 2507, 2015
The purpose of this paper is to study the effect of heat treatment on sliding wear property of su... more The purpose of this paper is to study the effect of heat treatment on sliding wear property of super duplex stainless steel SAF 2507.Sliding wear volume determined as a function of aging temperature. Four different aging temperatures were selected 700C, 800C, 900C, and 1000C .The specimens remained at these temperatures for 60 minutes and then quenched in water. During aging super duplex stainless steel SAF 2507 various transformations at microstructure will induced involving precipitation of chromium carbides and nitrides, sigma (σ) phase and other intermetalic phases which influence the wear property. The specimens aged at (800C) exhibit highest wear resistance.
Burnishing process, 2018
Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resis... more Burnishing is a cold working process improves surface roughness, wear resistance, corrosion resistance… etc. by introducing residual compressive stress into the surface of the work piece. In this study five pass of burnishing process was applied to machined 15 mm diameter AISI 316L austenitic stainless steel in five different depth of burnishing (0.1, 0.2, 0.3, 0.4 and 0.5 mm), burnishing time was one minute and spindle speed were 1050 rpm and 1800 rpm. Surface roughness of burnishing surface was detected. At low spindle speed 1050 rpm the lower surface roughness of burnished surface can be obtained during burnishing austenitic stainless steel AISI 316L in fifth pass and depth of burnishing equal to 0.5 mm. While at higher spindle speed the best surface finish can be obtained during burnishing AISI 316L austenitic stainless steel in fourth pass and depth of burnishing equal to 0.4 mm.
Heliyon, 2023
The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However,... more The third-generation alloy, AA2198-T8, is highly recommended for the aerospace industry. However, it has come under scrutiny due to its high cost. This study aims to decrease the cost of manufacturing through a hybrid design that uses AA2198-T8 alloys for the crucial parts and AA2024-T3 alloys for the remaining structure. The two main techniques for joining AA2024-T3 to AA2198-T8 are reversed double-sided friction stir welding (DS-FSW) and traditional single-sided friction welding (SS-FSW). They were carried out under unaltered tool rotation speed followed by five different welding speeds. The mechanical properties of the joints were explored, and the maximum joining efficiency of the welding process was 96% for reversed DS-FSW at 102 mm/min welding speed. The hybrid joint was tested for compliance with ASTM G34 standards to examine the welding joint's exfoliation corrosion (EXCO) for eight exposure times. The findings showed that joint efficiency decreased relative to as-welded joints, and mechanical property deterioration increased with EXCO exposure duration, reaching 40% for specimens exposed for 120 h to the corroding solution. It has been noted that morphology and grain size changes significantly impact EXCO.
Advances in Materials Science and Engineering
The study presents the hybrid joining of the third generation AA2198-T8 aluminum lithium alloy to... more The study presents the hybrid joining of the third generation AA2198-T8 aluminum lithium alloy to AA2024-T3 aluminum copper alloy, which has been highly demanded recently in the aerospace industry. This investigation aims to reduce the cost of production in the industrial sector. As a result, an affordable alternative is to use hybrid designs using AA2198-T8 alloy in crucial parts and AA2024-T3 alloy in the rest of the structure. A joining method is required to create hybrid structures composed of last-generation and standard aluminum alloys. The joining process was successfully friction stir-welded using five different welding travel speeds—36, 76, 102, 146, and 216 mm/min—with an invariable spindle speed of 960 rev/min. Two reversed steps, double-sided friction stir welding (DS-FSW) and single-sided friction stir welding (SS-FSW) techniques with two appropriate tool designs, were employed to investigate the dissimilar material mechanical properties and their morphological changes....
Materials Research Express, 2019
In the brake friction composites (BFCs), fibres take part in significant attention as reinforceme... more In the brake friction composites (BFCs), fibres take part in significant attention as reinforcement in governing mechanical and thermal-mechanical properties. The current investigation aims to develop hybrid brake friction composites using recycled basalt-aramid fibre integration and to characterise for its mechanical and thermal properties. The experiments related to thermal (heat swell, loss of ignition and thermal conductivity) and mechanical (tensile, compression, flexural and impact) properties were conducted as per industrial standards. From the experimental investigations, it was concluded that fibre inclusion in the BFCs enhanced the mechanical and thermal properties considerably. Further, with the aid of scanning electron microscope (SEM), fracture interfaces of the tested friction composites were analyzed for various characteristics like pullout, void, fibre-matrix bonding etc.
MSc Thesis, 2013
In the present study, arc welding of the AISI 1045 steel is modelled by using 2D-FEM for three ty... more In the present study, arc welding of the AISI 1045 steel is modelled by using 2D-FEM for three types of welding groove; V, double V and U. The temperature distribution, microstructure, grain growth, and the hardness of the heat affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close value between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheating temperature
on the martensite formation is analysed. It is shown that 225oC, 300oC and 350oC preheatings
eliminate completely the martensite formation for 12 mm thick, V, U and
double V-shaped butt welding of AISI 1045 steel. Among the welding grooves, the Vshape
is providing the lowest martensite formation and the lowest preheating
temperature for martensite elimination.