2024-03-29T19:18:32+04:30 http://jwsti.iut.ac.ir/browse.php?mag_id=3&slc_lang=fa&sid=1
3-93 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Evaluation of microstructure and mechanical properties of 410NiMo as an overlay layer on low alloy steel H. Ghasemi Tabasi hgt2006@gmail.com A. H. Kokabi The aim of this study is to reach an increased service life for parts using in sour environment by weld overlaying process. In this investigation, two successive layers of ER410NiMo were clad on low alloy steel substrates. To reduce the likelihood of Hydrogen Induced Cracking (HIC) and producing stable hydrogen traps, Post Weld Heat Treatment (PWHT) was conducted. Microstructural analysis, X-ray diffraction studies, and mechanical tests show significant increase for austenite volume fraction after second stage of PWHT. In fact, not only two-stage PWHT  reduce the samples hardness, but it also increases austenite volume fraction which is a more resistant microstructure against hydrogen cracking. Weld overlaying Hydrogen sulfide Hydrogen embrittlement Martensitic stainless steel Temper 2016 11 01 2 14 http://jwsti.iut.ac.ir/article-1-93-en.pdf
3-94 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Effect of geometrical variable and welding sequence on residual stresses and deformation in a 5083-H321 aluminum T joint S. Ansari E. Ranjbarnodeh islam_ranjbar@yahoo.com M. Iranmanesh Studies on welding process of Aluminium weldments shows that post-weld residual stress and deformation are influential on structure efficiency and there are different variable which affect these stresses and deformation. In this study the effect of geometrical variables and welding sequence on residual stresses and deformation in Aluminium H321 have investigated by the finite element software Ansys. Thermo elastic-plastic model was verified by metallography experiment and measurement of post-weld deformation afterward, weld leg, penetration depth and welding sequence were optimized to minimize the distortion. It was concluded that weld-volume increase post-weld distortion and it can be minimize by choosing an appropriate weld sequence friction Geometry Sequence Residual stress and distortion T joint 5083-H321 aluminum 2016 11 01 15 26 http://jwsti.iut.ac.ir/article-1-94-en.pdf
3-95 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Effect of heat treatment on the grain structure and mechanical properties of Al-7075 friction stir weld M. Mohammadi Zahrani mohsen.mohammadi@ma.iut.ac.ir M. Shamanian The fine grain structure of friction-stir welded aluminum alloys is unstable during post weld heat treatment and some grains abnormally grown. In this study, the sequence of abnormal grain growth during T6 heat treatment of Al-7075 friction-stir weld and its effect on mechanical properties of the weld was studied. The results showed that heat treatment in 510 ˚C resulted in drastic grain growth in stir zone and fine equiaxed grains in the stir zone of as-welded joint were substituted by millimeter-scale irregular grains. Post weld heat treatment resulted in decrease in the tensile elongation from about 10% to 1.5% although the joint tensile strength improved by 28%. In addition, post weld heat treatment changed the fracture location from the  heat-affected zone to the stir zone. Friction-stir welding Al-7075 Microstructure Abnormal grain growth Mechanical properties 2016 11 01 27 37 http://jwsti.iut.ac.ir/article-1-95-en.pdf
3-96 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Investigation on effect of holding time in brazing of steel to cemented carbide using Cu-Ag alloy filler metal M. Amelzadeh S. E. Mirsalehi Nowadays, cemented carbides-steels joints by brazing method are taken into consideration. One of the problems of these joints is the creation residual stresses that can reduce it with choose correct parameters of brazing. In this study, Silver base alloy filler containing copper, zinc and cadmium have been used in temperature 780°C and the effect of time parameter 5, 10 and 15 minutes on microstructure and mechanical properties were investigated. The results indicated that brazing in 15 minutes causes a columnar growth of solid solution phase of copper from cemented carbide side to steel and provides maximum strength of 94MPa. As well as, by passing of time wetting angle of cemented carbide surface reduces from 40° to about 27°. Cemented Carbide Steel Brazing Microstructure Mechanical Properties 2016 11 01 38 46 http://jwsti.iut.ac.ir/article-1-96-en.pdf
3-97 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Modeling of weld penetration in SAW process in the presence of boehmite nano-particles surface adsorbed by boric acid using MLP-ANN Y. Mollapour M. Aghakhani m.aghakhani@razi.ac.ir H. Eskandari H. Azarioun2 This paper investigates the effect of boehmite nano-particles surface adsorbed byboric acid (BNBA) along with other input welding parameters such as welding current, arc voltage, welding speed, nozzle-to-plate distance on weld penetration. Weld penetration modeling was carried out using multi-layer perceptron artificial neural network (MPANN) technique. For the sake of training the network, 70% of the obtained data from experimentation using five-level five-factor central composite rotatable design of experiments was used. The performance of the network shows a good agreement between the experimental data and the data obtained from the network. Hence, it is to be concluded that MPANN is highly accurate in predicting the weld penetration in SAW process. Submerged arc welding Weld penetration Boehmite nano-particles ANN 2016 11 01 47 55 http://jwsti.iut.ac.ir/article-1-97-en.pdf
3-98 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Optimization of gas tungsten arc welding (GTAW) to develop the NiAl coating using neural networks and genetic algorithm Hamid Gharaei h.gharaei@ma.iut.ac.ir Mahdi Salehi Mehran Nahvi Behzad Sadeghian In this research, artificial neural network (ANN) and genetic algorithm (GA) were used in order to produce and develop the NiAl intermetallic coating with the best wear behavior and the most value of hardness. The effect of variations of current, voltage and gas flow on the hardness and wear resistance were optimized by ANN and GA. In the following, the optimum  values of current, voltage and gas flow were obtained 90(A), 10(v) and 9 (Lit/min), respectively. Then, the wear behavior in the environment temperature and high temperature for optimized NiAl compound was compared with two other experimental samples. Intermetallic NiAl compound Cladding Artificial neural networks Genetic algorithm High temperature wear 2016 11 01 56 70 http://jwsti.iut.ac.ir/article-1-98-en.pdf
3-99 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Optimization of pulesd current gas tungsten arc welding process parameters to attain maximum weld metal toughness ofAISI 316/A387 Gr.91 weld joints with Taguchi method Mohammad Jula Reza Dehmolaei Dehmolaei@scu.ac.ir Seyed Reza Alavi Zaree In this paper, maximum value of energy to break at Charpy impact test as a criterion of fracture toughness of AISI 316/A387 Gr.91 weld joints with ERNiCrMo-3 filler metal were obtained by optimization of pulesd current gas tungsten arc welding process parameters. The selected parameters were peak current, background current, frequency and on time percentage that were changed in three levels. Therefore a L9 orthogonal array of Taguchi design including nine experiments for four parameters with three levels (34) was used. Analysis of signal to noise (S/N) ratio indicated that optimized values of peak current, background current, frequency and on time percentage were 120A, 90A, 10Hz and 80%, respectively. The welded specimen with optimized parameters showed an energy to break at Charpy impact test value of 65J at -20°c. The obtained results also demonstrated that the most influence on energy to break values belonged to background current, frequency, peak current and on time percentage, respectively.  Weld metal fracture toughness pulesd current gas tungsten arc welding Taguchi method AISI 316 steel A387 Gr.91 steel 2016 11 01 71 83 http://jwsti.iut.ac.ir/article-1-99-en.pdf
3-100 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Investigation on the corrosion behaviour of 420 welding martensitic steel with the ER308L, ER309L and ER420 fillers studied in 3.5% NaCl solution with and without CO2 Mahdi Lashkari Ghoochani Behrooz Beidokhti b.beidokhti@gmail.com In this research 420 martensitic stainless steel welded with the ER308L, ER309L and ER420 fillers by GTAW method. The corrosion properties of  the samples has been studied in 3.5% NaCl solution with and without CO2. Potentiodynamic polarization used to obtain the ER308L and ER309L have the best corrosion properties. In addition the welding process makes the 420 HAZ zone to be sensitized. The pitting potential of the samples has been decreased in presence of carbon dioxide. Furthermore, by adding CO2 to the solution the pH has been decreased and the corrosion potential reached near the -500 mV/SCE and the passivity current is also lowered. Corrosion Welding Stainless steel Martensit Potentiodynamic polarization 2016 11 01 84 91 http://jwsti.iut.ac.ir/article-1-100-en.pdf
3-101 2024-03-29 10.1002
Journal of Welding Science and Technology of Iran JWSTI 2476-583X 2676-6787 2016 2 2 Resistance spot welding of AISI 201 stainless steel: The relationship between welding current, microstructure, mechanical properties and failure mode M. Safari H. Mostaan In this paper, resistance spot welding process of AISI 201 stainless steel is studied experimentally. For this purpose, effect of welding current on quality of weld is investigated and relationships between welding current and fusion zone characteristics are examined. For determining mechanical properties such as maximum load and fracture mode, tensile - shear test of spot welds is performed.  Hardness and microstructural examinations are performed for study the influence of welding current on characteristics of welded joints. The results show that strength of resistance spot welds of AISI 201 stainless steel is increased with increase in welding current. Transition of fracture mode from interfacial to pullout and then pullout with tearing of sheet mode during tensile-shear tests of AISI 201 spot welds is investigated through experimental and theoretical approaches. It is concluded from results that increasing in welding current leads to change in fracture mode from interfacial to pullout mode due to increase in fusion zone size (weld nugget size). Also, it is observed that increasing in fusion zone size is accompanied by an increase in load carrying capacity of resistance spot welds. The minimum required fusion zone size to ensure pullout fracture mode is estimated using an analytical model.  Resistance spot welding AISI 201 stainless steel Microstructural evolution Mechanical properties Fracture mode 2016 11 01 92 105 http://jwsti.iut.ac.ir/article-1-101-en.pdf