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List of Articles kamran amini

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1 - Corrosion Behavior Characterization of the Nugget Zone in Copper/Brass Metals of Dissimilar Friction Stir Welded Lap Joints
kamran amini Farhad Gharavi

The electrochemical behavior of the weld nugget zone (WNZ) in copper-brass plates was studied in this paper. These plates were welded by the friction stir lap welding method in 1M NaCl solution at low heating input (450 rpm-25 mm/min ) and high heating input (710 rpm-16 More

The electrochemical behavior of the weld nugget zone (WNZ) in copper-brass plates was studied in this paper. These plates were welded by the friction stir lap welding method in 1M NaCl solution at low heating input (450 rpm-25 mm/min ) and high heating input (710 rpm-16 mm/min) by using the electrochemical impedance spectroscopy (EIS) and Tafel polarization at ambient temperature. The morphology of nugget zone corroded surfaces was analyzed by SEM (scanning electron microscopy) technique. The welding process appeared to decrease the corrosion resistance of the welded nugget regions through increasing the welding heat input. The results from EIS measurements presented the welded joints of NZ which showed higher and lower values respectively than brass and copper. Due to changing of microstructural of weld nugget zone during welding process, the Icorr of nugget zone enhances with increasing welding heat input. In fact, the surface corrosion morphology analysis revealed that the surface of welded sample by high heating input was shielded with a roughly porous corrosion layer rather than the surface of the welded sample at low heating input Manuscript profile
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2 - Investigating the Effect of Manganese Content on the Properties of High Manganese Austenitic Steels
Seyyed Amin Torabi Kamran Amini Masab Naseri

In this study, in order to investigate the effect of increasing the manganese content on microstructure and mechanical properties of high manganese austenitic steels, three alloys with successive increases in weight percentages of manganese (7.55, 13.1, and 16.5) and ca More

In this study, in order to investigate the effect of increasing the manganese content on microstructure and mechanical properties of high manganese austenitic steels, three alloys with successive increases in weight percentages of manganese (7.55, 13.1, and 16.5) and carbon (0.8 and 1.2) were cast in the presence of a constant amount of chromium (1.5 wt.%) and silica (0.6 wt.%). The samples experienced solution annealing heat treatment comprised of austenitizing at 1100°C for 2 h followed by rapid quenching in stirred water. Hardness, tensile, and wear tests were conducted by dry sand/rubber-wheel abrasion method. Microstructural observations were performed by using optical (OM) and scanning electron microscopies (SEM) and energy dispersive spectroscopy (EDS). The obtained results revealed that after heat treatment a uniform austenite structure has developed in all three samples. With increase of weight percent of the elements from sample 1 to sample 3, the hardness value reaches from 191 to 218 Vickers. Also, with increase of manganese weight percent from 7.55 to 16.5, the ultimate tensile strength and wear resistance showed 11% and 29% increase, respectively, to the effect that the most enhanced mechanical properties and maximum wear resistance were observed in sample 3 with 16.5wt.% of manganese. This improvement in mechanical properties and wear resistance is related to the formation of the solid solution in the matrix, the increase of hardenability, and the increase of work hardening capacity resulted from the increase of manganese percentage. Examination of the abraded surfaces demonstrated that the involved wear mechanism was scratch wear mechanism. Manuscript profile
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3 - Effect of the Number of Welding Passes on the Microstructure and Wear Behavior of St52 Plain Carbon Steel Coated with a High Chromium-Carbon Electrode
Mohsen Barmaki Kamran Amini Farhad Gharavi

This study investigated the effect of the number of welding passes on the microstructure, hardness, and wear behavior of St52 plain carbon steel coated with an E10-UM-60R electrode in accordance with the DIN 8555 standard using SMAW method. An optical microscope (OM) an More

This study investigated the effect of the number of welding passes on the microstructure, hardness, and wear behavior of St52 plain carbon steel coated with an E10-UM-60R electrode in accordance with the DIN 8555 standard using SMAW method. An optical microscope (OM) and a scanning electron microscope (SEM) were used, and an EDS analysis was carried out to examine the microstructure. The Vickers micro hardness test and a reciprocating wear test were also used to examine the hardness and wear resistance. The results showed that the structure on the surface of the coated specimens is consisted of M7C3 carbides in the eutectic field (). In addition, the volume fraction of carbides increased in specimens that underwent two passes of welding relative to that in one pass-welded specimen. The reason for this was related to the decreased dilution of iron and increased dilution of chromium in the two-pass welded specimen and an increase in the volume fraction of M7C3 carbides. The increased percentage of carbides in the two-pass welded specimen increased the hardness and consequently the wear resistance relative to those in the one-pass welded specimen in a way that the surface hardness and weight loss in the wear test reached from 780 HV and 3.7 mg in the one-pass welded specimen to 910 HV and 2.5 mg in the two-pass welded specimen. Moreover, examining the wear surfaces indicated the occurrence of an adhesive wear mechanism in the specimens in a way that the adhesive wear rate decreased in the two-pass welded specimens. Manuscript profile
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4 - Influence of Tool Offset Distance on Microstructure and Mechanical Properties of the Dissimilar AA2024–AA7075 Plates Joined by Friction Stir Welding
Hossain Soleimany kamran amini Farhad Gharavi
10.30495/admt.2021.1897512.1193

In the present study, the effect of tool offset on microstructure and mechanical properties of dissimilar friction stir welding of Al2024 and Al7075 alloys were investigated. In this regard, base metals were welded by FSW under different tool offsetting conditions, 1.5 More

In the present study, the effect of tool offset on microstructure and mechanical properties of dissimilar friction stir welding of Al2024 and Al7075 alloys were investigated. In this regard, base metals were welded by FSW under different tool offsetting conditions, 1.5 and 2 mm shifted into Al2024 and Al7075 alloys, respectively, in addition to constant rotation rates and traverse speeds named as 710 rpm and 28 mm/min respectively. The microstructure of different welding zones and fracture surface were investigated by an Optical Microscope (OM) and Scanning Electron Microscopy (SEM), respectively. The results showed that by tool offsetting from the weld center through Al2024, an onion-shaped area has been created and mixture happens completely. However, by tool off-setting towards Al7075, onion-shaped microstructure fails to be formed in the stirred area. From the results of the tensile test, it is presented that maximum tensile strength is obtained in samples with a tool offsetting into the Al7075. With 1.5 mm tool offsetting into Al2024, first, joint tensile strength increases by 22.2 % in comparison to non-offset condition, and then, with more tool offset as much as 2 mm, tensile strength decreases by 22.2 %. In addition, by tool offsetting towards Al7075 by 1.5 and 2 mm, joint tensile strength decreases by 4.5 and 28.5 %, respectively. It is also concluded that in the offset samples towards the 7075 alloy, the microhardness in the HAZ area decreased compared to the microhardness of the offsets samples towards the 2024 alloy. Finally, the best mechanical behavior and microstructural properties were obtained in the sample with the tool offset of about 1.5 mm towards the welded Al2024 base metal (70215 samples) alloy. Manuscript profile

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