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WOS: 000514814600011, The use of aluminum alloys in industry have been increased in due to their excellent low weight, corrosion resistance also other good features. Different aluminum alloys are joined with together when need of a structure presents different physical or mechanical properties with together. in this study, different aluminum alloys AA5754 and AA6013 joined by GMAW (gas metal arc welding) method under different welding parameters. After that, three-point bending test was carried out and notch impact test was performed to determine toughness behavior of the joints. in addition, the weld zone is characterized with hardness test and microstructure studies. While the welded samples joined with convenient parameters were bended 180 degrees, the cracks and fractures were occurred on the fusion line boundary of some samples due to unsuitable parameters. According to impact toughness test results, the highest toughness value was obtained from the HAZ (Heat affected zone) of AA5754. Besides, toughness values evaluated from the HAZ of AA6013 on the joints and weld metal were nearly same. With respect to hardness test results, the maximum hardness value was measured at the HAZ of AA6013 and this was followed by the weld metal and the HAZ of AA5754 sequentially. From the point of microstructure inspections, structures of all the weld metals were dendritic.

The use of aluminum alloys to reduce weight in air, sea, and land vehicles is increasing rapidly, especially due to their low density, excellent corrosion resistance, good forming properties, and increasable mechanical properties. A common aspect of all the relevant industrial sectors is the need to join the many parts of manufactured technological products using welding methods. In these industries, using welding to join different aluminum alloys having high mechanical properties is especially important. However, despite the widespread usage areas, it is very difficult to join different aluminums and their alloys via welding. In this study, AA5754/AA6013 aluminum alloys were joined using automatic gas metal arc welding (GMAW). Welded joints were created at two different welding speeds (150 and 180 mm/min) and three different welding current values (130, 140, and 150 A). This study investigated the microstructural and mechanical properties of AA5754/AA6013 aluminum alloy sheets joined at different welding speeds and current values. The macro and microstructures of samples taken from the welded joints were examined. In addition, hardness, tensile, bending, and fatigue tests were performed on the welded samples. The findings obtained as a result of the tests were evaluated and interpreted in light of the literature. Karabuk University Scientific Research Project CommitteeKarabuk University [KBUBAP-17-DR-406] The authors would like to thank the Karabuk University Scientific Research Project Committee for providing funding for this study (Project No. KBUBAP-17-DR-406) . WOS:000691196000005 2-s2.0-85112379090

WOS: 000490124400003 Aluminum alloys exhibit good strength, excellent corrosion resistance and good forming properties along with low specific density. Due to these superior properties, they are widely used in the automotive, chemical, and food industries, especially in shipbuilding and the yacht industry. It is important to join these alloys used in the mentioned industrial areas. However, it is very difficult to join Al and its alloys via traditional welding methods despite its widespread use. In this study, 5754-H111 and 6013-T6 aluminum alloys were joined by friction stir welding. Welding operations were carried out at 1250 rpm using welding feed rates of 12.5, 25, and 32 mm x min(-1). Metallographic investigations were carried out to determine the microstructural and macrostructural properties of the weld zones. Tensile, bending, and hardness tests were also performed to determine the mechanical properties of the welded samples. The results obtained as a result of the tests were evaluated and interpreted. Micro-void defects were found to occur in the weld metal-HAZ transition zones. It was established that the welding speed affected the tensile strength. The highest tensile strength was obtained at a feed rate of 25 mm x min(-1). It was determined that no cracking or fraction occurred in the welded samples as a result of the bending test. Karabuk UniversityKarabuk University [KBUBAP-17-DR-406] The authors would like to thank the Karabuk University Scientific Research Project Committee for the provision of funding for KBUBAP-17-DR-406.

Diffusion welding/bonding has been successfully used to joint dissimilar metals widely. In this study, pure Ti and AISI 430 ferritic stainless steel plates were joined through diffusion welding using a Ni interlayer at various temperatures (800, 825, 850 and 875 °C), holding times (15, 30, 60 and 120 min) and under a constant pressure (3 MPa) under argon shielding media. The welded joints were subjected to tensile-shear tests and hardness tests in order to determine their interfacial strength. In addition, microstructural properties of the joined interface were examined using optical and scanning electron microscope (SEM). The tensile-shear test results showed that the fractures occurred mostly in the interface of the Ni-ferritic stainless steel web at lower temperatures. It was seen from the hardness results that the highest hardness value was obtained for the titanium side and the hardness values increased with increasing welding temperature and holding time. SEM/EDS examinations showed that the diffused atoms and diffusion distance increased depending on the increasing temperature and holding time.

In this study, AISI 316L series austenitic stainless steel sheets were joined by tungsten inert gas welding method in continuous and pulsed currents. Regarding microstructural investigation and hardness values of weld metal, samples were welded to investigate the effect of current type on grain structures of weld metal. Results showed that samples welded by using pulsed current had considerable different properties compared to the samples welded by using continuous current. While the weld metals of joinings obtained by using continuous current displayed a coarse-grained and columnar structure, weld metals obtained by using pulsed current had a finer-grained structure. It was also found that hardness values of samples, which were welded with continuous and pulsed current, were quite different.

Sevim, Ibrahim/0000-0003-0582-4992; kaya, yakup/0000-0002-9951-2844 WOS: 000319557200056 In this article, Metal Inert Gas (MIG) weldability of commercially received and aged samples of 6061-T-6 and 7075-T-651 aluminum alloys was investigated. The welding joints were prepared in ten different combinations. Microstructure, microhardness, EDX, energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analyses were used in order to evaluate the effect of aged heat treatment on the performance of welded joints. In addition, the mechanical properties of welding joints were characterized using the tensile and microhardness tests. In conclusion, it was shown that prewelding aging heat treatment improves the mechanical properties of welding joints.

In the present study, Ti–6Al–4V alloy was bonded to electrolytic copper at various temperatures of 875, 890 and 900 °C and times of 15, 30 and 60 min through diffusion bonding. 3 MPa uniaxial load was applied during the diffusion bonding. Interface quality of the joints was assessed by microhardness and shear testing. Also, the bonding interfaces were analysed by means of optical microscopy, scanning electron microscopy and energy dispersive spectrometer. The bonding of Ti–6Al–4V to Cu was successfully achieved by diffusion bonding method. The maximum shear strength was found to be 2171 N for the specimen bonded at 890 °C for 60 min. The maximum hardness values were obtained from the area next to the interface in titanium side of the joint. The hardness values were found to decrease with increasing distance from the interface in titanium side while it remained constant in copper side. It was seen that the diffusion transition zone near the interface consists of various phases of βCu 4 Ti, Cu 2 Ti, Cu 3 Ti 2 , Cu 4 Ti 3 and CuTi.

Titanium and low carbon steel plates were joined through diffusion bonding using a silver interlayer at various temperatures for various diffusion times. In order to determine the strength of the resulting joints, tensile-shear tests and hardness tests were applied. Additionally, optical, scanning electron microscopy examinations and energy dispersive spectrometry elemental analyses were carried out to determine the interface properties of the joint. The work showed that the highest interface strength was obtained for the specimens joined at 850 °C for 90 min. It was seen from the hardness results that the highest hardness value was obtained for the interlayer material and the hardness values on the both sides of the interlayer decreased gradually as the distance from the joint increased. In energy dispersive spectrometry analyses, it was seen that the amount of silver in the interlayer decreased markedly depending on the temperature rise. In addition, increasing diffusion time also caused some slight decrease in the amount of silver.

In this study, commercially pure (CP) titanium sheets (ASTM Grade 2) were welded by resistance spot welding at different welding parameters and under different welding environments. The welded joints were subjected to tensile-shearing tests in order to determine the strength of the welded zones. In addition, hardness and microstructural examinations were carried out in order to examine the influence of welding parameters on the welded joints. The results showed that increasing current time and electrode force increased the tensile shearing strength and the joints obtained under the argon atmosphere gave better tensile-shearing strength. Hardness measurement results indicated that welding nugget gave the highest hardness and the heat affected zone (HAZ) and the base metal followed this. The argon gas used during the welding process was seen to have no influence on the hardness values. Microstructural examinations revealed that the deformations took place in the welding zone during welding. The twinning took place in the grains. High electrode force and high weld cycles, were used during the welding, increased the twinning. © 2005 Elsevier Ltd. All rights reserved.

In this study, Ti6Al4V alloy plates and commercial copper plates were bonded through explosive welding process. Different amounts of explosive material were used to investigate its influence on the bonding interface. Elbar-5 powders were used as explosive material and the bonding process was carried out through oblique geometry method. Microstructures of the bonded sections were examined and then tensile-shearing tests and hardness measurements were carried out on the bonded specimens. Tensile-shearing tests results showed that shear and fracture took place in the copper plates not in the joining interface. The highest hardness value was measured from the zone near the joining interface. Microstructural examination showed that with increasing explosive material amount the length and amplitude of the waviness in the interface were increased. SEM studies showed that no traces of intermetalics were observed in the interface. (c) 2005 Elsevier B.V. All rights reserved.

The purpose of this study is to produce composite plates through explosive welding process widely used in developed countries and is of great importance to produce such plates and unfortunately currently its use in our country is not common. In this study, stainless steel-titanium plates were joined explosively employing oblique geometry route at different explosive ratios. The bonding was investigated using optical and scanning electron microscopy and tensile-shearing, bending, hardness and corrosion tests were carried out. Optical and scanning electron microscopy examinations showed that a transition was observed from smooth bonding interface to a wavy one with increasing explosive ratio. It was also observed that grains near the interface were elongated parallel to the explosion direction. No shearing within the interface was seen from the tensile-shear tests and fracture took place within the low strength material. The bended specimens showed that defects such as separation and tearing were not observed. Hardness was increased with increasing explosive ratio and the highest hardness values were obtained near the bonding interface. Weight increase due to formation of a stable oxide layer on the welded stainless steel-titanium plates was seen from corrosion tests while weight loss was seen from the other specimens and this loss was increased with increasing explosive ratio. © 2005 Elsevier B.V. All rights reserved.