@article{ author = {Hajizadeh, M. and Emami, S. and Saeid, T.}, title = {Influence of rotational speed on the development of microstructure in a friction stir welded 304 austenitic stainless steel}, abstract ={Friction stir welding was conducted on AISI 304 austenitic stainless steel sheet with dimensions of 100 mm × 100 mm × 2 mm. The FSW was performed at a welding speed of 150 mm/min and rotational speeds of 400 and 800 rpm. The results showed that high frequency of low angle grain boundaries (LAGBs) were formed through dynamic recovery in the thermo-mechanically affected zone (TMAZ). Higher amount of LAGBs were developed in the TMAZ of welded sample with 800 rpm due to the higher amount of strain and heat generated. High fraction of high angle grain boundaries were formed in the stir zone (SZ) of the welded samples through the occurrence of continuous dynamic recrystallization (CDRX). A very fine microstructure developed in the sampled welded with lower rotational speed. Analysis of texture using {111} Pole figures showed the formation of shear texture components in the SZ of both welded samples. The intensity of the obtained texture for the sample welded with 800 rpm was greater. The formation of shear texture components in the SZ of both samples implied the occurrence of CDRX mechanism}, Keywords = {Friction stir welding, Stainless steels, Dynamic recovery, Dynamic recrystallization, Shear texture}, volume = {6}, Number = {1}, pages = {1-8}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-290-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-290-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {DelirNazarlou, Ramin and Omidbakhsh, Faraz and MollaeiMilani, Jav}, title = {Effect of rotational speed in friction stir welding on the material transfer mechanism in commercial pure aluminum}, abstract ={Friction stir welding (FSW) is an economic and high quality technique at aluminum welding and joining methods. The most important factor in the soundness of this type of welding, is the mechanism of material transfer in each tool rotation. The materials transfer during the welding process involves horizontal and vertical movement that caused by extrusion process and forging force (the tilt angle due to forging force and on the other hand, shape of pin due to the extrusion process). One of the most important parameters in FSW process is the effect of rotational speed in the welded zone. In this study, the effect of rotational speed at constant welding speed, in the butt joint of pure commercial aluminum, was investigated. The results of the study showed that, increasing the rotational speed due to increases the amount of material transfer in the weld zone. The welded zone was investigated by appearance weld zone experiments and using radiography tests. Also weld zone was investigated in macro and microstructure by using cross section. Then the micro hardness testing has been used by cross section at welded zone. In order to investigate the mechanism of materials transfer during the process, the electrical resistivity test has been used to analyses the amount of materials transfer in the weld zone. Results shows that, increasing rotational speed due to increasing the amount of materials transfer in the weld zone and decreasing the amount of defects in the weld zone.  }, Keywords = {Friction stir welding, Material flow path, radiography, Rotational Speed, Pure commercial Aluminum}, volume = {6}, Number = {1}, pages = {9-17}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-245-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-245-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {HashemiMilani, S. A. A. and Tavangar, R. and Azadbeh, M. and Kahinpoor, and Sadeghi-Nasab, H.}, title = {Effect of NOCOLOK® flux dry-off temperature on brazed joint strength of aluminum-based heat exchangers}, abstract ={During the brazing of aluminum-based heat exchangers, the flux dry-off temperature plays a crucial role to get sound joints with maximum strength. In the present study, the NOCOLOK® flux consists of two phases of K2AlF5.H2O and KAlF4 with a melting point around 580 °C was used for brazing AA3003 as base metal with a clad-coating of AA4343 as filler metal. The slurry was applied on the joints and they dried at 220, 300 and 380 °C in air. The tensile shear test revealed that when the slurry dried at 300 °C, the joint withstand maximum shear stress of 44 MPa without defective features. At 220 °C and 380 °C, joint shear stresses were 34 MPa, 30 MPa respectively. However, drying at 380 °C under protective nitrogen gas enhanced the shear strength of up to 39 MPa. Having applied a change in current dryer temperature in the factory from 360 °C to 300 °C reduced the percentage of heat exchangers leakage from 3.2% to 0.6%, approximately, on a weekly basis.}, Keywords = {Brazing of aluminum, NOCOLOK® flux, Aluminum-silicon.}, volume = {6}, Number = {1}, pages = {19-32}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-293-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-293-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {F.Pahnaneh, and M.Aghakhani*, and R.EslamiFarsani, and M.Karamipour1,}, title = {Analysis and predicting the effect of ZrO2 nano-particles on penetration and HMZ in GMAW of low carbon steel using fuzzy logic}, abstract ={This paper reports the applicability of fuzzy logig (FL) to predict the hardness of melt zone (HMZ) during the gas metal arc welding (GMAW) process, which is affected by the combined effect of ZrO2 nano-particles and welding input parameters. The arc voltage, welding current, welding speed, stick-out, and ZrO2 nano-particles were used as the input parameters and HMZ as the response to develop FL model. The predicted results from FL were compared with the experimental data. The most important input parameter affecting the HMZs was the addition of ZrO2 nanoparticle coatings with a thickness of 1 mm, which increased the hardness from 78 to 84 HRB. The correlation factor value obtained was 99.98% between the measured and predicted values of HMZ. The results showed that FL is an accurate and reliable technique for predicting HMZ because of its low error rate. Also, the presence of ZrO2 nano-particles in the weld pool has increased the penetration up to 2 times.  }, Keywords = {Gas metal arc welding, Hardness of melted zone, ZrO2 nano-particles, Fuzzy logic, Weld penetration.}, volume = {6}, Number = {1}, pages = {33-48}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-299-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-299-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {S.Emami, and T.Saeid,}, title = {Friction stir welding of accumulative roll bonded single phase brass}, abstract ={Single phase brass strips with 2 mm thickness were severely deformed through 1 and 3 cycles of accumulative roll bonding process (ARB). ARB process effectively increased the hardness, yield strength, and the ultimate strength of the processed materials. The hardness of processed material increased from 95 HV in annealed material to 225 HV in 3 cycle ARBed material, and the yielding and ultimate strengths increased more than 5 and 2 times of the annealed sample, respectively. Friction stir welding (FSW) process was successfully conducted on the annealed and ARBed samples to investigate and compare the microstructure and the mechanical properties of the joints obtained in bead on plate configuration. Microstructural observations showed that very fine dynamically recrystallized grains developed in the stir zones (SZs) of all welded samples. Mechanical properties were evaluated by hardness and tensile testing. Hardness test for the ARBed and FS welded samples showed that the hardness value decreased by 110 Hv in the resultant SZs. Results of tensile testing revealed that yield and ultimate strength of the FS welded ARBed samples 1.3 and 1.8 times are greater than that of the annealed FS welded sample .}, Keywords = {Severe plastic deformation, Friction stir welding, Single phase brass, Dynamic recrystallization.}, volume = {6}, Number = {1}, pages = {49-55}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-300-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-300-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Ghandi, A. and Shamanian, M. and Salmani3, M. R.}, title = {Investigation of structural changes in resistance spot welding of advanced high strength steel DP590}, abstract ={The structural and hardness developed in advanced high-strength steel DP590 have been investigated with the help of optical microscopy and scanning electron microscopy on resistance spot welded specimens. The hardness diagram of the weld sections was prepared by microhardness test and the temperature peak and heat distribution were simulated by menas of the Abaqus software. The results show that according to the temperature generated in each region of the weld nugget, the HAZ and base metals have different microstructures, and these difference affects the hardness of the regions. The presence of tempered martensite islands with a fraction of 44% in ferrite matrix in base metal, mainly martensitic structure in the nugget, and martensitic structure along with scattered areas of ferrite in the HAZ was observed. The results of the microhardness tests showed difference in hardness values of the regions, and also it was observed that the hardness values increased in the HAZ and weld zone. The hardness values measured in the nugget, base metal, and HAZ were around 400, 200, and 450 HV which were in accordance with the observed structures}, Keywords = {Advanced high strength steel DP590, Spot resistance welding, Microstructure, Microhardness, Simulation}, volume = {6}, Number = {1}, pages = {57-65}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-301-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-301-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Alinaghian, H. R. and SadoughVanini, S. A. and MonirVaghefi, S. M.}, title = {Evaluation of microstructure and hardness in repair with OAW method in copper DHP moulds}, abstract ={The surface of continuous casting moulds with high number of castings may be worn or destructed. As result, an approach for increasing these moulds life is necessary. In this project, the goal is the restoration of the DHP copper sample. In this project, the destruction of the copper sample is done by creation of groove using a CNC machine. The restoration of the sample is done using OAW and filler to fill groove area. In this project, the effect of preheating temperature, filler type and heat treatment of welding area on hardness, microstructure, chemical analyses of welding area and thermal conductivity of the weld are investigated. The preheating temperature range of 300 to 450oC was selected. The Cu-P and Cu-Ag-P fillers were chosen to fill the groove of the weld area. The scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDS), micro hardness tester, optical microscope and thermal conductivity meter were employed for evaluation of the results in this project. The results showed that the increase of preheating temperature creates oxide layers and the decrease of preheating temperature causes the incomplete filling of the welding area. Finally, the preheating temperature of 400 oC was a proper choice considering the above mentioned factors. The stress relieving operation to decrease stress and preserve the mechanical properties in the temperature of 250 to 400 oC and duration two hours was carried out. The result demonstrated that the selected temperature causes no unwanted decrease on the hardness. It was also found that increasing the annealing duration, decreases the hardness of weld for Cu-P filler for Cu-Ag-P filler increasing the annealing duration, first decreases the weld hardness and then increases the weld hardness. The Cu-P filler was compared with Cu-Ag-P filler. The results showed that the Cu-Ag-P filler has less hardness (around 10 percent) than the filler without silver. On the other hand, the thermal conductivity of the Cu-Ag-P filler was around 10 percent more than the thermal conductivity of the Cu-P. It is obvious that the selection of the filler type depends on the type of base metal and its geometry. The results showed that the segregation in the Cu-P filler with 7.2 percent phosphorous, because of the proximity of the weld structure to the eutectic point, has slightly happened; while, the selection of the Cu-Ag-P filler with 6 percent silver caused severe segregation of silver to 90 percent silver at the center of weld at the non-dendrite area}, Keywords = {DHP copper, Repair of failing, Welding filler, Micro-hardness, Microstructure, Annealing}, volume = {6}, Number = {1}, pages = {67-80}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-302-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-302-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {}, title = {Effect of the TLP process parameters on microstructure, mechanical properties and corrosion resistance of 316L stainless steel to pure commercial titanium joint with pure copper interface}, abstract ={In this research, effect of time and temperature of TLP process on the microstructure, mechanical properties and corrosion resistance of CP-Ti to 316L stainless steel joint evaluated. For this purpose pure copper foil with 100 µm thickness was used as interlayer and joining process carried out at 950˚C, 1000˚C and 1050˚C and for 90, 120 and 150 minutes. After the joining process, shear and micro-hardness test and corrosion resistance were applied in the samples. The test results revealed that the shear strength of the sample 1000˚C is better than two other soaking temperatures. The main reason was the formation of less intermetallic compounds at the interface, as well as the presence of less athermally solidification zone area. Microstructural examinations for the sample after TLP at 950˚C revealed no iron and titanium bearing intermetallic compounds in the interface while for two other samples, there exist considerable amount of intermetallics in the microstructure. Corrosion test results showed that the resistance against corrosion depends on the intermetallic compounds formed in the interface. Intermetallic phases includes FeTi, TiCu, Ti2Cu, and TiCu2. The sample prepared at 1000˚C for 120 minutes had less intermetallic compounds and as a result, had the best corrosion resistance. Fe and Ti containing intermetallics had good corrosion resistance in simulated body fluid, as comparison with Ti and Cu containing compounds.}, Keywords = {Transitional liquid phase bonding process, Dissimilar metal bonding, 316 L steel, Commercial pure titanium.}, volume = {6}, Number = {1}, pages = {81-95}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-305-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-305-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Rostami, M. and Khorsand, H.}, title = {Optimal SQUID based non-destructive test for detecting sub-surface defects with the help of advanced SQUID superconducting sensors and an experimental approach for optimal production method of these sensors from the YBCO superconductor materials}, abstract ={The conventional eddy current method for non-destructive inspection of welding joints has limitations that can examine defects to a certain depth below the surface of the sample and is not suitable for determining deep defects. This limitation can be overcome using the SQUID superconducting sensors. The nonstoichiometric composition of YBCO due to its superconducting temperature and desired critical current density is widely used including the use of highly sensitive SQUID sensors. The properties and temperature of the superconducting compound are related to producing pure and homogeneous with a precise ratio of this non-stoichiometric compound in phase Y:123. In this study, the production of this high-temperature superconductor was carried out using a sol gel self-combustion process with nitrate forming elements and then produced powder analyzed by TGA, XRD, scanning electron microscopy, and EDX method and optimum conditions for production of Y:123 superconducting nanopowder were obtained by sol gel self-combustion method. In these conditions, the superconducting phase Y:123 was produced and the impurities were removed and on the other hand, the need for further thermal treatment and the costly annealing process were removed. Finally, optimal conditions for deposition of this compound on the substrate for producing the SQUID sensor were investigated and an optimal condition was presented to produce thin layer YBCO deposited by pulsed laser deposition method and patterned to produce SQUID High temperature Superconductor SQUID sensor. Finally the SQUID based NDT test for detecting sub-surfaces defects was investigated.}, Keywords = {High temperature superconductor, SQUID, YBCO, SrTiO3 substrate, Sol-gel self-combustion, Non-destructive test.}, volume = {6}, Number = {1}, pages = {97-113}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-306-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-306-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Bekrani, M.}, title = {Phased array ultrasonic imaging using an improved beamforming based total focusing method for non destructive test}, abstract ={One of the novel ultrasonic phased array based scanning methods for ultrasonic imaging in non-destructive test is total focusing method (TFM). This method employs maximum available information of the phased array elements and leads to an improved defect detection accuracy compared to conventional scanning methods. Despite its high detection accuracy, TFM behaves weak in distinguishing the real defects from noise which is because of its high background noise level. In this paper, a low complexity technique is presented for performance improvement of TFM which employs a beamforming method on the phased array received signals and leads to a reduction of the background noise and increase in the accuracy of the defect detection. To this end, a thresholding technique along with three-level clipping of the array received data is applied for low-complexity approximation of the correlation matrix inverse employed in the beamforming. Experimental results for detection of drilled holes on a steel pipe show a background noise reduction of 4.45 dB and improvement in the hole distinction of about 3 dB in comparison to those of TFM. In addition, as shown in the simulation results, the minimum distinguishable distance between two neighbor reflector points for the proposed method is 0.21 mm which is 0.23 mm lower than that for TFM.}, Keywords = {Ultrasonic phased array, Non-destructive testing, Welding inspection, Total focusing method, Beamforming.}, volume = {6}, Number = {1}, pages = {115-132}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-307-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-307-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Samadi, M.R. and Mostaan, H. and Rafiei, M. and Salehi, M.}, title = {A study on the effect of pulsed current gas tungsten arc welding parameters on the microstructural evolutions, corrosion behavior and mechanical properties of AA 5456 weld joints}, abstract ={Nowadays, aluminum and its alloys have extensive applications in marine and aerospace industrious owing to their excellent properties. Among these alloys, 5xxx series of aluminum alloys have also excellent corrosion resistance, high toughness and strength and also good weldability. Decrease in yield strength and also tensile strength due to the grain growth in the heat affected zone is of the main problems in the welding of these series of Al alloys. In this research work, gas tungsten arc weld joints in two modes i. e. direct current and pulsed current were compared in order to study the effect of this parameter on the microstructure, mechanical properties and corrosion resistance of weld joints. Also, the effect pulsed current parameters such as peak current and basic current were investigated. Microstructural evolutions and fracture surfaces of weld joints were examined by optical microscope and scanning electron microscope, respectively. It was found that the fracture behavior of all joints is in a ductile manner. Also, tensile test and electrochemical polarization were conducted in order to study the mechanical properties and corrosion behavior of weld joints.}, Keywords = {5xxx series Al alloys, Filler metal, Gas tungsten arc welding, Corrosion, Microstructure}, volume = {6}, Number = {1}, pages = {133-146}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-308-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-308-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Shayanfar, P. and Daneshmanesh, H. and Janghorban, K.}, title = {The effect of overlapping percent on microstructure and mechanical properties of laser cladding of Inconel 625 powder on ASTM A592 steel}, abstract ={In this study, the effect of overlapping percentage on microstructure and mechanical properties of a single-pass coating by Inconel 625 powder laser has been investigated for quench-tempered ASTM A592 steel. In order to have a structural analysis, the inter dendritic distance was evaluated. For this purpose, scanning electron microscopy (FESEM) and Digimizer software were adopted. In order to investigate mechanical properties, elastic modulus, toughness, and micro hardness were evaluated. For the evaluation of elastic modulus, Noop indentation method was used, and for toughness studies, Evans method was applied. After the investigation, it was found that in the overlapping of single-pass 50% coatings, the heat input value is lower than overlapping in single-pass 75% coatings. It also contains a finer structure with much higher mechanical properties. This is in such a way that the inter dendritic distance in single-pass 50% coatings is about 0.91 µm. The average diameter of the dendritic columns is about 0.32 µm, hardness value is about 10%, Knoop hardness is about 9 units, elastic modulus is about 37 GPa, and toughness is about 9 MPa m1/2 higher in comparison with the 75% overlapping case.}, Keywords = {Laser cladding, Inconel 625, A592 steel, Microstructure, Mechanical properties}, volume = {6}, Number = {1}, pages = {147-156}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-309-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-309-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Ebrahimzadeh, H. and Farhangi, H.}, title = {Fabrication of synchronized hammer peening with pulsed laser welding and its effect on 6061 aluminum alloy weld}, abstract ={The non-continuous laser beam in pulsed lasers allows the mechanical peening between two consecutive beams on a still hot weld bead. At a very short time (20, 150 and 300 ms) after laser pulse application, mechanical peening was performed on the welding bead. To achieve these short times, the light sensor detects the nth laser pulse and the mechanical arm starts moving. Upon reaching the tip of the pin near the workpiece, the n + 1th pulse was irradiated to the workpiece surface, and so the pin impact to the weld bead after traveling a short distance. Desirable mechanical properties were obtained at the highest time (300 ms) and highest pressure (6 bars). In this time and pressure the weld beads were not broken due to bending forces of peening.}, Keywords = {Pulsed laser welding, Synchronized hammer peening, 6061 aluminum alloy, Delay time, Pneumatic pressure, Mechanical properties.}, volume = {6}, Number = {2}, pages = {1-12}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-321-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-321-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Ashiri, R. and Shamanian, M. and Salimijazi, H. R. and Park, Y. and Salmani, M. R.}, title = {Welding challenges facing advanced automotive steels in resistance spot welding process: A review}, abstract ={Nowadays, the use of advanced high strength steels (AHSSs) in body-in-white is one of the hot applied strategies which is followed by the most of the automakers. The study of weldability and weld challenges facing these steels in resistance spot welding process as the most widely used process in the assembly lines of the automotive industry is essential to use the outstanding mechanical responses of AHSSs. This study can result in improvement of mechanical performance of the resistance spot welds of AHSSs. Our results indicate that AHSSs experiences different welding challenges which this work aims to study them by discussing their causes, mechanisms involved and potential ways to address them.}, Keywords = {Advanced automotive steels, Resistance spot welding, Weldability, Susceptibility to welding defects and discontinuities, Segregation}, volume = {6}, Number = {2}, pages = {13-27}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-325-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-325-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {GhorbaniAmir, Y. and Zolriasatein, A. and Torabian, H.}, title = {Effect of rotary friction welding variables on mechanical and physical properties of aluminum-copper tube joints}, abstract ={The aim of this study is to investigate the effect of rotary frictional welding process variables on microstructure, mechanical and physical properties of copper-aluminum dual-tube pipes. For this purpose, using a thermosetting friction welding machine, a copper pipe (99.44% purity) with a similar diameter aluminum tube (1050), was welded in three different conditions with different friction pressures and forging, and then by metallographic, hardening and microstructural testing it placed. The results of this study showed that with increasing friction pressure from 10 and 15 Bar respectively, in the interconnected phase, fuzzy interclass metal samples were created and caused a great loss in the deformation percentage and tensile strength of the interconnected sample. Also, with the reduction of frictional pressure and the removal of forging pressures down to 5 Bar, there is no proper bond between the two samples and formed in the interface between porosity and cracking. The most suitable result for the microstructure, mechanical and physical properties of the samples is in tubes with an outside diameter of 15 mm and an inner diameter of 10 mm, for samples having a friction pressure of about 10 Bar and a forge pressure of 15 Bar. The presence of intermetallic Al-Cu phases such as CuAl2, due to higher electrical resistance and ceramic nature, increases the electrical resistance of the joint and, on the other hand, the presence of cracks and pores has reduced the flow rate and eventually increased electrical resistance of the samples}, Keywords = {Rotary frictional welding, Tube sections, Aluminum-copper joints}, volume = {6}, Number = {2}, pages = {29-39}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-326-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-326-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {LoriAmini, A. and Sabet, H. and GhanbariHaghighi, M.}, title = {The effect of activated flux type on the weld profile and angular distortion of A-TIG welding of the AISI 2205 duplex stainless steel}, abstract ={In this investigation, the AISI 2205 duplex stainless steel was welded in the form of bead on plate by A-TIG process with different amount of the ZrO2 and TiO2 activated fluxes. The results of the visual inspection showed that the specimen with 50% ZrO2 and 50% TiO2 activated flux, had the lowest face width and the specimen with contains 90% ZrO2 activated flux, had the highest penetration depth. Also, the results showed that the angular distortion of the specimens with mix of the ZrO2 and TiO2 activated flux were 225% less than the specimen without activated flux. The results of macroscopic examination of different samples showed that the maximum length and width of the macroscopic grains were related to the sample with 90% ZrO2 activated flux and the smallest length and width of the macroscopic grains were related to the sample with 90% TiO2 activated flux. The hardness test results showed that the highest hardness of the samples was gained to 90% TiO2 activated flux specimen with 950 HV and the lowest hardness value for the sample with 90% ZrO2 activated flux with 410 HV. The results of all tests showed that surface activated fluxes (ZrO2 and TiO2) affected to the depth of penetration, face width, angular distortion, length and width of macroscopic grains and the hardness of weld metal by changing the longitudinal and transverse melt flow in the weld pool.}, Keywords = {A-TIG welding process, Duplex stainless steel, Activated flux.}, volume = {6}, Number = {2}, pages = {41-51}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-327-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-327-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Safari, M. and DeilamiAzodi, H.}, title = {Experimental study of formability of friction stir welded ultra-thin sheets of IF steel}, abstract ={In this paper, the experimental investigation of formability of friction stir welded ultra-thin sheets of IF steel is investigated experimentally. First, the sheets are joined by friction stir welding process based on the tests determined according to the Taguchi design of experiments. The investigated parameters in the welding process are as tool rotational and traverse speeds. Then, the tailor welded blanks are formed based on dome height test up to the defect stage and the dome height is measured for each test. Therefore, the effects of friction stir welding process parameters on formability of friction stir welded ultra-thin sheets of IF steel are evaluated. The results show that by increasing the rotational speed, the dome height in forming process decreases, while with increasing the traverse speed, the formability of tailor welded blanks by friction stir welding process improves.  Also, the results of optimization based on signal to noise ratio method show that the tool rotational speed has the greatest effect on the dome height of tailor welded blank.   }, Keywords = {Rotary frictional welding, Tube sections, Aluminum-copper joints.}, volume = {6}, Number = {2}, pages = {53-63}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-328-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-328-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Yousefieh, M. and Jabbari, A.}, title = {Modeling of temperature in friction stir welding of duplex stainless steel using multivariate lagrangian methods, linear extrapolation and multiple linear regression}, abstract ={In this study, the temperature in friction stir welding of duplex stainless steel has been investigated. At first, temperature estimation was modeled and estimated at different distances from the center of the stir zone by the multivariate Lagrangian function. Then, the linear extrapolation method and multiple linear regression method were used to estimate the temperature outside the range and center of the stir zone. Temperature estimation is based on three parameters rotational speed, welding speed and distance from the center of stir zone. In the first method, by generalizing the multivariate Lagrangian method, the multivariate Lagrangian temperature function was generalized according to the above parameters. In the second method, in order to investigate the effect of the variables in the regression model, a comparison of two complete models and a reduced model based on the sum of squares errors was used. Then, by analyzing the multiple regression equations governing the output variable, a multiple linear regression function was introduced. Since the temperature of the stir zone is not measurable by the thermocouple, so in general the best fit curve for estimating the function is when the modeling is based on parameters that minimize the error function.To implement the multiple linear regression method, the error function was introduced to minimize the sum of the error squares and the error derivative was calculated in relation to the parameters of tool rotation speed, welding speed and distance from the center of the stir zone. Therefore, multiple linear regression method was considered as the basic method and as a criterion with other methods. According to the results obtained from the prediction in the center of the stir zone, the temperature difference in all three methods is desirable and negligible. The maximum temperature difference of multiple linear regression method with multivariate Lagrangian method in all nodes was 18.8 oC and multiple linear regression method with linear extrapolation method was 26.36 oC. Therefore, the multivariate Lagrangian interpolation method is less different than the linear extrapolation method in the center of the stir zone and is more accurate.}, Keywords = {Duplex stainless steel, Friction stir welding, Multivariate lagrangian interpolation, Linear extrapolation, Multiple linear regression.}, volume = {6}, Number = {2}, pages = {65-76}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-329-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-329-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {BeheshtiBafqi, S. A. and Mosallaee, M.}, title = {The effect of bonding temperature on the characteristics of TLP bonded joints in AISI 2205/BNi-3/AISI 2205 assembly}, abstract ={In the present study, the transient liquid phase bonding of AISI 2205 dual phase stainless steel with amorphous BNi-3 interlayer was carried out. Based on the initial experimental and analytical studies, the parameters of temperature and bonding time were determined. In order to investigate the effect of bonding temperature on the microstructural changes of the joint, bonding was performed in the temperature range of 1050-1200℃ for 20 min. The microstructural and phase analyses indicated the completion of isothermal solidification and the formation of a uniform Ni-solid solution in the bonding zone centerline. The interdiffusion between the bonding zone and the adjacent base metal resulted in the formation of boride and nitride intermetallic compounds in the base metal adjacent to the bonding zone, which the area fraction of this intermetallics significantly decreased with increasing bonding temperature from 1050℃ to 1200℃ (reduction of the intermetallic area fraction from 85% to 40%). Evaluation of shear strength of samples showed that despite the completion of isothermal solidification in all samples and shear strength of bonded samples significantly depends of amount and morphology of intermetallic compounds on the transient liquid phase bonding shear strength. By increasing the bonding temperature to 1200℃ and reducing the area fraction of intermetallic compounds up to 40% of the shear strength of the samples increased from 450 MPa of TLP bonded specimen of 1050℃ to about 85% of base metal shear strength.}, Keywords = {Transient liquid phase bonding, Diffusion affected zone,AISI 2205, Cr-Boride, Microstructure.}, volume = {6}, Number = {2}, pages = {77-89}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-330-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-330-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Dehmolaei, R. and RaeisiSarani, M. S. and Ranjbar, K.}, title = {The evaluation of microstructure and mechanical properties of API 5L X80/DSS 2205 weld metals produced by PCGTAW}, abstract ={}, Keywords = {}, volume = {6}, Number = {2}, pages = {91-102}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-331-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-331-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Anvari, S. Z. and Daneshpour, S. and Oshaghi, S.}, title = {Microstructure and mechanical properties evaluation of diffusion bonded joints of titanium to AISI 304 austenitic stainless steel}, abstract ={In this study, diffusion bonding between titanium and AISI 304 austenitic stainless steel by Ag interlayer was investigated. In order to carry out this research, samples prepared after surface preparation were placed inside the fixture and placed at the temperatures of 750,800 and 850 °C in the 30,60 and 90 min in the furnace under argon protective gas. The phase transformation and microstructure of diffusion bonding interfaces of the joints were studied using optical microscopy, scanning electron microscopy and x-ray diffraction. Then, the hardness of the samples was measured using a hardness test apparatus. Finally, the samples were tested after being placed in the shear strength test holder using a pressure test device and the shear strength of the samples was measured. Examination of optical microscopic images shows the diffusion of silver in titanium and the partial diffusion of silver in stainless steel. On the other hand, increasing the temperature increases the diffusion region as well as increasing the grain size in the specimens. SEM images from the samples also confirmed the diffusion of silver in titanium and partially diffusion into stainless steel. The results of the XRD test on the samples showed that the temperature rise to 800 °C leads to the formation of TiAg and Ag3Fe2 intermetallic compounds, which the existence of TiAg intermetallic compound increases the hardness of the sample. For this reason, the sample at 800 °C showed the highest hardness. The shear strength of the samples showed that the increase in temperature increased the shear strength of the samples and decreased the shear strength by increasing the temperature above 850 ° C due to the formation of brittle intermetallic compounds.}, Keywords = {Titanium, Stainless steel, Diffusion bonding, Interlayer.}, volume = {6}, Number = {2}, pages = {103-117}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-344-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-344-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Shahryari, Z. and Keivanrad, I. and Gheisari, K. and Ranjbar, K. and Dehmolaei, R. and Mousavi, S. R.}, title = {Corrosion behavior of dissimilar welded joint between Inconel 617 alloy and A387-Gr.11 low-alloy steel}, abstract ={In this study, Inconel 617 alloy was welded to A387-Gr.11 low-alloy steel using ER309L filler metal via gas tungsten arc welding (GTAW). First, the corrosion behavior of Inconel 617, A387-Gr, and the weld metal was evaluated by the Tafel polarization test and electrochemical impedance spectroscopy (EIS) in acidic (H2SO4), neutral (NaCl), and combined (H2SO4 + NaCl) solution at ambient temperature. The results of polarization and EIS measurements in all corrosive solutions indicate that the corrosion resistance decreases from 617 alloy to weld metal and from weld metal to low-alloy steel, respectively. The Comparison of the polarization curves of the base metals and the weld metal showed susceptibility to galvanic corrosion between Inconel 617 / weld metal in 1M NaCl solution. The behavior of galvanic corrosion of this pair was evaluated using the mixed potential theory and the electrochemical noise measurement. The results showed that in a galvanic couple of alloy 617 / weld metal, the weld metal acts as anode and corrodes in such a way that its corrosion rate increases from 0.22 μA/cm2 before joining to 1 μA /cm2 after joining.}, Keywords = {Inconel 617 alloy, A387-Gr.11 steel, GTAW, Tafel polarization, Impedance spectroscopy, Electrochemical noise analysis.}, volume = {6}, Number = {2}, pages = {119-135}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-335-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-335-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {JabariRad, A. and Akbari, D. and Golzar, M.}, title = {Ultrasonic welding of thermoset matrix composites reinforced with glass fibers using a co-cured retaining layer}, abstract ={In this paper, ultrasonic welding of glass fiber reinforced thermoses, co-cured whit a thermoplastic has been studied. Co-curing process forms a connection between the thermoset and the thermoplastic while curing the composite. Considering that the calculated stress should not be related to the dimensions of the sample, a horn with a tip dimension smaller than the standard overlap was used. The results show that the actual weld dimensions are bigger than the intended weld dimensions. This has happened due to the movement of the melted thermoplastic to the sideways during the welding. The design of experiment has been done using response surface central composite, and a quadratic equation based on the lap shear strength of the welds containing three principle parameters time, force and amplitude was suggested, as well as predicting the optimum values. The equation shows that the force is an insignificant factor. In the samples with a higher time value the thermosetting resin started to degrade. The dominant failure mode of the specimens is segregation between the thermoset and fibers. The results show that the optimum parameters can result in a lap shear strength of 28.2 MPa, which is a very decent value compared to other methods of joining.  }, Keywords = {Ultrasonic welding, Thermoset, Co-curing.}, volume = {6}, Number = {2}, pages = {137-144}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-336-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-336-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} } @article{ author = {Soltanipour, A.R. and Soltanipour, A.R. and Farmanesh, K.}, title = {Evaluation of fatigue behavior of cast and ultra-fine processed Al-7075 by using friction stir technique}, abstract ={ This paper presents experimental results on the fatigue properties of the modified microstructure of cost Al-alloy 7075 via friction stir processing (FSP). The microstructural behavior was investigated by using optical microscope (OM). The grain size of cast FSP-ed at different locations was investigated via XRD. Uniaxial tensile and bending fatigue tests were carried out at room temperature on both cast and after FSP conditions. Fatigue properties were investigated using a fully reversible bending testing machine. Significance enhancement of mechanical properties was attributes to the elimination of porosities as well as uniform distribution of ultra-fine grains throughout the matrix. A fractographic study was done to understand the fracture behavior being changed from quasi-cleavage fracture to dimple fracture. The resultant ultra-fine grain structure causes significant increasing in tensile and fatigue properties.  }, Keywords = {}, volume = {6}, Number = {2}, pages = {145-160}, publisher = {Iranian Institute of Welding and Non Destructive Testing}, url = {http://jwsti.iut.ac.ir/article-1-337-en.html}, eprint = {http://jwsti.iut.ac.ir/article-1-337-en.pdf}, journal = {Journal of Welding Science and Technology of Iran}, issn = {2476-583X}, eissn = {2676-6787}, year = {2020} }