The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Toshihiko Koseki - One of the best experts on this subject based on the ideXlab platform.
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Friction stir welding of multilayered steel
Science and Technology of Welding and Joining, 2012Co-Authors: J. Taendl, Norbert Enzinger, Junya Inoue, Shoichi Nambu, Toshihiko KosekiAbstract:This study investigates the mechanical properties and microstructure of friction stir butt welded high strength/ductility multilayered steel consisting of 15 alternating layers of SUS 301 austenitic stainless steel (eight layers) and SUS 420J2 martensitic stainless steel (seven layers) with a total thickness of 1·2 mm. With optimised welding parameters, defect free welds with an ultimate tensile strength (UTS) of 1240 MPa and a Fracture Elongation of 13% were accomplished. This corresponds to a joint efficiency of 90%. In this case, Fracture occurred in the heat affected zone as a result of a very pronounced hardness drop in the martensitic layers resulting from the formation of a large amount of grain boundary precipitates, which were formed at temperatures ∼750°C slightly below Ac1. By applying post-weld heat treatment, the hardness drop in the martensitic layers was removed and the tensile properties were enhanced to UTS of 1310 MPa (95% joint efficiency) and a Fracture Elongation of 22%.
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Fracture Elongation of brittle/ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
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Fracture Elongation of brittle ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
Junya Inoue - One of the best experts on this subject based on the ideXlab platform.
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Friction stir welding of multilayered steel
Science and Technology of Welding and Joining, 2012Co-Authors: J. Taendl, Norbert Enzinger, Junya Inoue, Shoichi Nambu, Toshihiko KosekiAbstract:This study investigates the mechanical properties and microstructure of friction stir butt welded high strength/ductility multilayered steel consisting of 15 alternating layers of SUS 301 austenitic stainless steel (eight layers) and SUS 420J2 martensitic stainless steel (seven layers) with a total thickness of 1·2 mm. With optimised welding parameters, defect free welds with an ultimate tensile strength (UTS) of 1240 MPa and a Fracture Elongation of 13% were accomplished. This corresponds to a joint efficiency of 90%. In this case, Fracture occurred in the heat affected zone as a result of a very pronounced hardness drop in the martensitic layers resulting from the formation of a large amount of grain boundary precipitates, which were formed at temperatures ∼750°C slightly below Ac1. By applying post-weld heat treatment, the hardness drop in the martensitic layers was removed and the tensile properties were enhanced to UTS of 1310 MPa (95% joint efficiency) and a Fracture Elongation of 22%.
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Fracture Elongation of brittle/ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
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Fracture Elongation of brittle ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
X. T. Hong - One of the best experts on this subject based on the ideXlab platform.
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orientation related specimen thickness effects on mechanical properties of hot extruded az31b magnesium alloy
Materials & Design, 2013Co-Authors: X P Zhang, S F Feng, X. T. HongAbstract:Abstract Microforming is a well-suited technology to manufacture very small metallic parts, in particular for mass production. Microforming is a plastic deformation forming technology. It is frequently found the material properties of wrought-metal products with stock size are not the same in all directions. The aspect of orientation dependency of the mechanical properties has been sufficiently investigated and reported in literatures. However, there are few literatures on the influence of orientation on the specimen size effect of material properties. The aim of this work is to study the specimen size effects of hot extruded magnesium alloys and their correlation with specimen orientation (or load direction). Tensile properties of a hot extruded AZ31B magnesium alloy were investigated using different specimen thicknesses in the range from 0.25 mm to 2 mm and three orientations at room temperature. Influences of the orientations on the size effects of the mechanical properties were also studied. Major results of the present work included: firstly, obvious size effect on mechanical properties of the alloy could be observed, and secondly, the size effects on the tensile strength depended on the orientations. The tensile yield strength and the tensile strength of the alloy along the extrusion direction increased with the specimen thickness, while these along the transverse direction and the 45 o direction decreased with the thickness. The Elongation percentage of the three orientations decreased with the thickness. The orientation affected the failure mode and the value of the Fracture Elongation. However, the orientation did not influence the size effects of failure mode and Fracture Elongation.
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Orientation-related specimen thickness effects on mechanical properties of hot extruded AZ31B magnesium alloy
Materials and Design, 2013Co-Authors: X P Zhang, X. T. Hong, S F Feng, J. Q. LiuAbstract:Microforming is a well-suited technology to manufacture very small metallic parts, in particular for mass production. Microforming is a plastic deformation forming technology. It is frequently found the material properties of wrought-metal products with stock size are not the same in all directions. The aspect of orientation dependency of the mechanical properties has been sufficiently investigated and reported in literatures. However, there are few literatures on the influence of orientation on the specimen size effect of material properties. The aim of this work is to study the specimen size effects of hot extruded magnesium alloys and their correlation with specimen orientation (or load direction). Tensile properties of a hot extruded AZ31B magnesium alloy were investigated using different specimen thicknesses in the range from 0.25mm to 2mm and three orientations at room temperature. Influences of the orientations on the size effects of the mechanical properties were also studied. Major results of the present work included: firstly, obvious size effect on mechanical properties of the alloy could be observed, and secondly, the size effects on the tensile strength depended on the orientations. The tensile yield strength and the tensile strength of the alloy along the extrusion direction increased with the specimen thickness, while these along the transverse direction and the 45 o direction decreased with the thickness. The Elongation percentage of the three orientations decreased with the thickness. The orientation affected the failure mode and the value of the Fracture Elongation. However, the orientation did not influence the size effects of failure mode and Fracture Elongation. © 2012 Elsevier Ltd.
Shoichi Nambu - One of the best experts on this subject based on the ideXlab platform.
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Friction stir welding of multilayered steel
Science and Technology of Welding and Joining, 2012Co-Authors: J. Taendl, Norbert Enzinger, Junya Inoue, Shoichi Nambu, Toshihiko KosekiAbstract:This study investigates the mechanical properties and microstructure of friction stir butt welded high strength/ductility multilayered steel consisting of 15 alternating layers of SUS 301 austenitic stainless steel (eight layers) and SUS 420J2 martensitic stainless steel (seven layers) with a total thickness of 1·2 mm. With optimised welding parameters, defect free welds with an ultimate tensile strength (UTS) of 1240 MPa and a Fracture Elongation of 13% were accomplished. This corresponds to a joint efficiency of 90%. In this case, Fracture occurred in the heat affected zone as a result of a very pronounced hardness drop in the martensitic layers resulting from the formation of a large amount of grain boundary precipitates, which were formed at temperatures ∼750°C slightly below Ac1. By applying post-weld heat treatment, the hardness drop in the martensitic layers was removed and the tensile properties were enhanced to UTS of 1310 MPa (95% joint efficiency) and a Fracture Elongation of 22%.
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Friction stir welding of multilayered steel
Science and Technology of Welding and Joining, 2012Co-Authors: J. Taendl, Norbert Enzinger, J. Inoue, Shoichi Nambu, Tagami KosekiAbstract:This study investigates the mechanical properties and microstructure of friction stir butt welded high strength/ductility multilayered steel consisting of 15 alternating layers of SUS 301 austenitic stainless steel (eight layers) and SUS 420J2 martensitic stainless steel (seven layers) with a total thickness of 1·2 mm. With optimised welding parameters, defect free welds with an ultimate tensile strength (UTS) of 1240 MPa and a Fracture Elongation of 13% were accomplished. This corresponds to a joint efficiency of 90%. In this case, Fracture occurred in the heat affected zone as a result of a very pronounced hardness drop in the martensitic layers resulting from the formation of a large amount of grain boundary precipitates, which were formed at temperatures~750°C slightly below A c1. By applying post-weld heat treatment, the hardness drop in the martensitic layers was removed and the tensile properties were enhanced to UTS of 1310 MPa (95% joint efficiency) and a Fracture Elongation of 22%. © 2012 Institute of Materials, Minerals.
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Fracture Elongation of brittle/ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
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Fracture Elongation of brittle ductile multilayered steel composites with a strong interface
Scripta Materialia, 2008Co-Authors: Junya Inoue, Yoshitake Ishimoto, Shoichi Nambu, Toshihiko KosekiAbstract:The ductile tensile deformation behavior of multilayered steel composites consisting of brittle martensitic steel and ductile steel layers, which were prepared by hot rolling to achieve a strong interface, was investigated. A clear enhancement of the Fracture Elongation with decreased layer thickness was seen, while the tensile strength ratio between the constituent materials as well as the hardening exponent was found to be crucial for optimizing the ductility. A good strength–ductility balance, 1.2 GPa tensile strength and 15% uniform Elongation, was achieved solely using conventional steels.
X P Zhang - One of the best experts on this subject based on the ideXlab platform.
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orientation related specimen thickness effects on mechanical properties of hot extruded az31b magnesium alloy
Materials & Design, 2013Co-Authors: X P Zhang, S F Feng, X. T. HongAbstract:Abstract Microforming is a well-suited technology to manufacture very small metallic parts, in particular for mass production. Microforming is a plastic deformation forming technology. It is frequently found the material properties of wrought-metal products with stock size are not the same in all directions. The aspect of orientation dependency of the mechanical properties has been sufficiently investigated and reported in literatures. However, there are few literatures on the influence of orientation on the specimen size effect of material properties. The aim of this work is to study the specimen size effects of hot extruded magnesium alloys and their correlation with specimen orientation (or load direction). Tensile properties of a hot extruded AZ31B magnesium alloy were investigated using different specimen thicknesses in the range from 0.25 mm to 2 mm and three orientations at room temperature. Influences of the orientations on the size effects of the mechanical properties were also studied. Major results of the present work included: firstly, obvious size effect on mechanical properties of the alloy could be observed, and secondly, the size effects on the tensile strength depended on the orientations. The tensile yield strength and the tensile strength of the alloy along the extrusion direction increased with the specimen thickness, while these along the transverse direction and the 45 o direction decreased with the thickness. The Elongation percentage of the three orientations decreased with the thickness. The orientation affected the failure mode and the value of the Fracture Elongation. However, the orientation did not influence the size effects of failure mode and Fracture Elongation.
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Orientation-related specimen thickness effects on mechanical properties of hot extruded AZ31B magnesium alloy
Materials and Design, 2013Co-Authors: X P Zhang, X. T. Hong, S F Feng, J. Q. LiuAbstract:Microforming is a well-suited technology to manufacture very small metallic parts, in particular for mass production. Microforming is a plastic deformation forming technology. It is frequently found the material properties of wrought-metal products with stock size are not the same in all directions. The aspect of orientation dependency of the mechanical properties has been sufficiently investigated and reported in literatures. However, there are few literatures on the influence of orientation on the specimen size effect of material properties. The aim of this work is to study the specimen size effects of hot extruded magnesium alloys and their correlation with specimen orientation (or load direction). Tensile properties of a hot extruded AZ31B magnesium alloy were investigated using different specimen thicknesses in the range from 0.25mm to 2mm and three orientations at room temperature. Influences of the orientations on the size effects of the mechanical properties were also studied. Major results of the present work included: firstly, obvious size effect on mechanical properties of the alloy could be observed, and secondly, the size effects on the tensile strength depended on the orientations. The tensile yield strength and the tensile strength of the alloy along the extrusion direction increased with the specimen thickness, while these along the transverse direction and the 45 o direction decreased with the thickness. The Elongation percentage of the three orientations decreased with the thickness. The orientation affected the failure mode and the value of the Fracture Elongation. However, the orientation did not influence the size effects of failure mode and Fracture Elongation. © 2012 Elsevier Ltd.
