The existence of some problems in joining Al and Mg alloys using classical fusion welding methods... more The existence of some problems in joining Al and Mg alloys using classical fusion welding methods causes limitations in the use of Mg and Al alloys in common structures. Friction stir welding (FSW) is a solid-state welding method for joining materials having same or different properties at temperatures below their melting points. In this study, dissimilar alloys AZ31B Mg and Al6061 were joined by FSW at a feed rate of 34 mm·min−1 and at different tool rotational speeds (600 and 700 rpm) and material positions. During the welding process, AZ31B Mg plate was positioned at the advancing side and Al6061 was located at the retreating side, and moreover, the two alloys were also positioned vice versa. Tensile strength and microhardness tests were performed to examine the mechanical properties of the welded specimens. The microstructures of the welded zones were examined by obtaining the optical microscopic (OM) and scanning electron microscopic (SEM) images. The highest welding strength w...
Friction stir welding is a solid-state welding method for joining materials having the same or di... more Friction stir welding is a solid-state welding method for joining materials having the same or different properties at temperatures below their melting points. Generally, the welding parameters affect the microstructural and mechanical properties of welded specimens. In this study, AA5083 and AA5754 aluminium alloys were joined by friction stir welding at different tool rotation speeds of 450, 700, and 900 rpm, feed rates of 40, 50, and 80 mm min−1, and tilting angles of 0◦, 1◦, and 3◦ using a tapered stir pin. The effects of these welding parameters on the mechanical properties of the welded parts were examined by tensile and micro-hardness tests. Moreover, the welded joints were analysed using an optical microscope, scanning electron microscope, and energy dispersive X-ray spectroscopy. The results indicated that the specimen welded at 50 mmmin−1 feed rate, 450 rpm tool rotation speed, and a 1◦ tilting angle exhibited the highest welding strength and elongation values. K e y w o r...
The joining of magnesium alloys with conventional fusion welding methods often causes porosity an... more The joining of magnesium alloys with conventional fusion welding methods often causes porosity and hot cracking defects. The use of friction stir welding, a solid-state welding technique for joining Mg alloys, solves these problems. In this study, AZ31B Mg sheets with 3 mm in thickness were joined by friction stir welding at a constant feed rate (50 mm min −1) and different tool rotational speeds (900 and 1400 rpm), and different tool tilt angles (0 • and 1.5 •) using tapered pin. Tensile strength and microhardness tests were carried out to examine the mechanical properties of the welded specimens. The microstructures of the welded zone were analyzed by obtaining optical microscopy and scanning electron microscopy images. According to the tensile test results, specimen welded at 50 mm min −1 feed rate, 900 rpm tool rotational speed, and 1.5 • tool tilt angle showed the highest welding strength value 176.03 MPa.
Diffusion welding is one of the exclusive welding methods that provides a perfect material interf... more Diffusion welding is one of the exclusive welding methods that provides a perfect material interface after joining of different materials and results in high mechanical properties at high temperatures. In particular, this technique can be used for joining porcelain and metal that have distinctly different features. In this study, diffusion welding of copper to porcelain has been investigated. After the diffusion welding with different parameters, shear tests have been applied to the samples in order to investigate the weld properties and the changes in hardness in the weld region. In order to elucidate the changes in microstructure and composition in the weld region, SEM, EDX and XRD analyses were performed on the samples. As a result, the joining of copper and porcelain materials can successfully be performed by diffusion welding. Samples have the highest weld strength, if they are joined by diffusion welding at 900 °C for 60 min and at 4.5 MPa.
Bu calismada, difuzyon kaynagi ile birlestirilmis bakir ve porselen malzemelerin sonlu elemanlar ... more Bu calismada, difuzyon kaynagi ile birlestirilmis bakir ve porselen malzemelerin sonlu elemanlar yontemine gore termal ve yapisal analizleri arastirilmistir. Bakir ve porselen malzemeler; elektrik elektronik, elektromekanik ve uzay sanayinde, birlikte kullanilmaktadir. Ozel kaynak yontemlerinden biri olan difuzyon kaynagi; kusursuz bir ara yuzey ve yuksek sicaklikta mekanik direnc sagladigi icin bakir ve porselen malzemelerin birlestirilmesinde tercih edilmistir. Deneyler sonrasinda, kaynakli numunelere kesme testi uygulanarak kaynakli bolgenin mukavemeti arastirilmis ve sertlik degisimleri incelenmistir. Kesme testi sonuclarina gore, en iyi kaynak dayanimina sahip numunelerin parametreleri esas alinarak, sonlu elemanlar yontemine gore, bilgisayar destekli analiz programinda, termal analiz ve yapisal analiz yapilmistir. Analiz sonuclari ve deney sonuclari karsilastirilarak, her iki malzemede homojen isi dagilimi saglanana kadar deney esnasinda isitma ve sogutma sureleri arttirilmist...
Abstract Diffusion welding is one of the exclusive welding methods that provides a perfect materi... more Abstract Diffusion welding is one of the exclusive welding methods that provides a perfect material interface after joining of different materials and results in high mechanical properties at high temperatures. In particular, this technique can be used for joining porcelain and metal that have distinctly different features. In this study, diffusion welding of copper to porcelain has been investigated. After the diffusion welding with different parameters, shear tests have been applied to the samples in order to investigate the weld properties and the changes in hardness in the weld region. In order to elucidate the changes in microstructure and composition in the weld region, SEM, EDX and XRD analyses were performed on the samples. As a result, the joining of copper and porcelain materials can successfully be performed by diffusion welding. Samples have the highest weld strength, if they are joined by diffusion welding at 900 °C for 60 min and at 4.5 MPa.
AA5754Al alloy is widely used in industry. However, as in the case of all Al alloys, the 5xxx ser... more AA5754Al alloy is widely used in industry. However, as in the case of all Al alloys, the 5xxx series Al alloys cannot be easily joined through fusion welding techniques. To address this problem, in this study, the effect of double-sided friction stir welding at various tool rotational speeds (450, 710, and 900 rpm), feeding rates (40, 50, and 80 mm × min-1), and tool tilt angles (0°, 1°, 2°) on the welding parameters and mechanical and microstructural characteristics of AA5754 Al alloy was determined. Tensile strength tests and microhardness tests were performed to examine the mechanical properties of the welded specimens. The microstructures of the welded zone were examined by obtaining optical microscopy and scanning electron microscopy images. The tensile test results indicated that the specimens exhibited the highest welding performance of 95.17 % at a tool rotational speed, feed rate, and tool tilt angle of 450 rpm, 50 mm × min-1 and 1°, respectively.
Balıkesir Üniversitesi Fen Bilimleri Enstitüsü Dergisi
Sürtünme karıştırma kaynağı 1990'lı yılların başlarında ilk kez keşfedilmiştir. O yıllardan günüm... more Sürtünme karıştırma kaynağı 1990'lı yılların başlarında ilk kez keşfedilmiştir. O yıllardan günümüze değin endüstride pek çok alanda kullanılmıştır. Sürtünme karıştırma kaynağı, aynı veya farklı özellikteki malzemelerin, ergitme sıcaklığının altındaki sıcaklıklarda birleştirilmesinde kullanılan, bir katı hal kaynak yöntemidir. Kaynak işlemi sırasında kullanılan takımlar kaynaklı birleştirmenin metalurjik ve mekanik özelliklerini büyük oranda etkilemektedir. Takımların karıştırıcı uç geometrilerinin kaynaklı birleştirmenin dayanımında önemli ölçüde etkisi bulunmaktadır. Bu çalışmada da, EN AW-5754 ve EN AW-5083 alüminyum alaşımları, 450 d/dak devir sayısında, 50 mm/dak ilerleme hızında 0 derecelik omuz açısıyla, vidalı, konik ve silindirik karıştırıcı uçlu takımlarla, sürtünme karıştırma kaynağı ile birleştirilmişlerdir. Kaynak işlemi sonrasında numunelere, çekme testleri ve mikrosertlik testleri yapılarak kaynaklı bağlantıların mekanik özellikleri incelenmiştir. Kaynaklı numunelerin optik mikroskop görüntüleri alınarak metalurjik yapıları incelenmiştir. Kaynaklı numunelere yapılan çekme testi sonuçlarına göre, en iyi kaynak dayanımını; 188,76 MPa lık kaynak mukavemeti ile vidalı karıştırıcı uçla yapılan kaynaklı birleştirmeler göstermiştir. Ayrıca, mikro sertlik ve mikro yapı incelemeleri de bu sonucu desteklemektedir.
The existence of some problems in joining Al and Mg alloys using classical fusion welding methods... more The existence of some problems in joining Al and Mg alloys using classical fusion welding methods causes limitations in the use of Mg and Al alloys in common structures. Friction stir welding (FSW) is a solid-state welding method for joining materials having same or different properties at temperatures below their melting points. In this study, dissimilar alloys AZ31B Mg and Al6061 were joined by FSW at a feed rate of 34 mm·min−1 and at different tool rotational speeds (600 and 700 rpm) and material positions. During the welding process, AZ31B Mg plate was positioned at the advancing side and Al6061 was located at the retreating side, and moreover, the two alloys were also positioned vice versa. Tensile strength and microhardness tests were performed to examine the mechanical properties of the welded specimens. The microstructures of the welded zones were examined by obtaining the optical microscopic (OM) and scanning electron microscopic (SEM) images. The highest welding strength w...
Friction stir welding is a solid-state welding method for joining materials having the same or di... more Friction stir welding is a solid-state welding method for joining materials having the same or different properties at temperatures below their melting points. Generally, the welding parameters affect the microstructural and mechanical properties of welded specimens. In this study, AA5083 and AA5754 aluminium alloys were joined by friction stir welding at different tool rotation speeds of 450, 700, and 900 rpm, feed rates of 40, 50, and 80 mm min−1, and tilting angles of 0◦, 1◦, and 3◦ using a tapered stir pin. The effects of these welding parameters on the mechanical properties of the welded parts were examined by tensile and micro-hardness tests. Moreover, the welded joints were analysed using an optical microscope, scanning electron microscope, and energy dispersive X-ray spectroscopy. The results indicated that the specimen welded at 50 mmmin−1 feed rate, 450 rpm tool rotation speed, and a 1◦ tilting angle exhibited the highest welding strength and elongation values. K e y w o r...
The joining of magnesium alloys with conventional fusion welding methods often causes porosity an... more The joining of magnesium alloys with conventional fusion welding methods often causes porosity and hot cracking defects. The use of friction stir welding, a solid-state welding technique for joining Mg alloys, solves these problems. In this study, AZ31B Mg sheets with 3 mm in thickness were joined by friction stir welding at a constant feed rate (50 mm min −1) and different tool rotational speeds (900 and 1400 rpm), and different tool tilt angles (0 • and 1.5 •) using tapered pin. Tensile strength and microhardness tests were carried out to examine the mechanical properties of the welded specimens. The microstructures of the welded zone were analyzed by obtaining optical microscopy and scanning electron microscopy images. According to the tensile test results, specimen welded at 50 mm min −1 feed rate, 900 rpm tool rotational speed, and 1.5 • tool tilt angle showed the highest welding strength value 176.03 MPa.
Diffusion welding is one of the exclusive welding methods that provides a perfect material interf... more Diffusion welding is one of the exclusive welding methods that provides a perfect material interface after joining of different materials and results in high mechanical properties at high temperatures. In particular, this technique can be used for joining porcelain and metal that have distinctly different features. In this study, diffusion welding of copper to porcelain has been investigated. After the diffusion welding with different parameters, shear tests have been applied to the samples in order to investigate the weld properties and the changes in hardness in the weld region. In order to elucidate the changes in microstructure and composition in the weld region, SEM, EDX and XRD analyses were performed on the samples. As a result, the joining of copper and porcelain materials can successfully be performed by diffusion welding. Samples have the highest weld strength, if they are joined by diffusion welding at 900 °C for 60 min and at 4.5 MPa.
Bu calismada, difuzyon kaynagi ile birlestirilmis bakir ve porselen malzemelerin sonlu elemanlar ... more Bu calismada, difuzyon kaynagi ile birlestirilmis bakir ve porselen malzemelerin sonlu elemanlar yontemine gore termal ve yapisal analizleri arastirilmistir. Bakir ve porselen malzemeler; elektrik elektronik, elektromekanik ve uzay sanayinde, birlikte kullanilmaktadir. Ozel kaynak yontemlerinden biri olan difuzyon kaynagi; kusursuz bir ara yuzey ve yuksek sicaklikta mekanik direnc sagladigi icin bakir ve porselen malzemelerin birlestirilmesinde tercih edilmistir. Deneyler sonrasinda, kaynakli numunelere kesme testi uygulanarak kaynakli bolgenin mukavemeti arastirilmis ve sertlik degisimleri incelenmistir. Kesme testi sonuclarina gore, en iyi kaynak dayanimina sahip numunelerin parametreleri esas alinarak, sonlu elemanlar yontemine gore, bilgisayar destekli analiz programinda, termal analiz ve yapisal analiz yapilmistir. Analiz sonuclari ve deney sonuclari karsilastirilarak, her iki malzemede homojen isi dagilimi saglanana kadar deney esnasinda isitma ve sogutma sureleri arttirilmist...
Abstract Diffusion welding is one of the exclusive welding methods that provides a perfect materi... more Abstract Diffusion welding is one of the exclusive welding methods that provides a perfect material interface after joining of different materials and results in high mechanical properties at high temperatures. In particular, this technique can be used for joining porcelain and metal that have distinctly different features. In this study, diffusion welding of copper to porcelain has been investigated. After the diffusion welding with different parameters, shear tests have been applied to the samples in order to investigate the weld properties and the changes in hardness in the weld region. In order to elucidate the changes in microstructure and composition in the weld region, SEM, EDX and XRD analyses were performed on the samples. As a result, the joining of copper and porcelain materials can successfully be performed by diffusion welding. Samples have the highest weld strength, if they are joined by diffusion welding at 900 °C for 60 min and at 4.5 MPa.
AA5754Al alloy is widely used in industry. However, as in the case of all Al alloys, the 5xxx ser... more AA5754Al alloy is widely used in industry. However, as in the case of all Al alloys, the 5xxx series Al alloys cannot be easily joined through fusion welding techniques. To address this problem, in this study, the effect of double-sided friction stir welding at various tool rotational speeds (450, 710, and 900 rpm), feeding rates (40, 50, and 80 mm × min-1), and tool tilt angles (0°, 1°, 2°) on the welding parameters and mechanical and microstructural characteristics of AA5754 Al alloy was determined. Tensile strength tests and microhardness tests were performed to examine the mechanical properties of the welded specimens. The microstructures of the welded zone were examined by obtaining optical microscopy and scanning electron microscopy images. The tensile test results indicated that the specimens exhibited the highest welding performance of 95.17 % at a tool rotational speed, feed rate, and tool tilt angle of 450 rpm, 50 mm × min-1 and 1°, respectively.
Balıkesir Üniversitesi Fen Bilimleri Enstitüsü Dergisi
Sürtünme karıştırma kaynağı 1990'lı yılların başlarında ilk kez keşfedilmiştir. O yıllardan günüm... more Sürtünme karıştırma kaynağı 1990'lı yılların başlarında ilk kez keşfedilmiştir. O yıllardan günümüze değin endüstride pek çok alanda kullanılmıştır. Sürtünme karıştırma kaynağı, aynı veya farklı özellikteki malzemelerin, ergitme sıcaklığının altındaki sıcaklıklarda birleştirilmesinde kullanılan, bir katı hal kaynak yöntemidir. Kaynak işlemi sırasında kullanılan takımlar kaynaklı birleştirmenin metalurjik ve mekanik özelliklerini büyük oranda etkilemektedir. Takımların karıştırıcı uç geometrilerinin kaynaklı birleştirmenin dayanımında önemli ölçüde etkisi bulunmaktadır. Bu çalışmada da, EN AW-5754 ve EN AW-5083 alüminyum alaşımları, 450 d/dak devir sayısında, 50 mm/dak ilerleme hızında 0 derecelik omuz açısıyla, vidalı, konik ve silindirik karıştırıcı uçlu takımlarla, sürtünme karıştırma kaynağı ile birleştirilmişlerdir. Kaynak işlemi sonrasında numunelere, çekme testleri ve mikrosertlik testleri yapılarak kaynaklı bağlantıların mekanik özellikleri incelenmiştir. Kaynaklı numunelerin optik mikroskop görüntüleri alınarak metalurjik yapıları incelenmiştir. Kaynaklı numunelere yapılan çekme testi sonuçlarına göre, en iyi kaynak dayanımını; 188,76 MPa lık kaynak mukavemeti ile vidalı karıştırıcı uçla yapılan kaynaklı birleştirmeler göstermiştir. Ayrıca, mikro sertlik ve mikro yapı incelemeleri de bu sonucu desteklemektedir.
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