The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Kazuhiro Hono - One of the best experts on this subject based on the ideXlab platform.
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Microstructures and Tensile properties of a twin roll cast and heat-treated Mg-2.4Zn-0.1Ag-0.1Ca-0.1Zr alloy
Scripta Materialia, 2011Co-Authors: Chamini Lakshi Mendis, Jun Ho Bae, Nack J. Kim, Kazuhiro HonoAbstract:An Mg–2.4Zn–0.1Ag–0.1Ca–0.1Zr alloy sheet, with a Tensile Yield Strength of 316 MPa, an ultimate Tensile Strength of 342 MPa and an elongation of 17%, has been processed by twin roll casting (TRC), hot rolling and heat treatment. The high Yield Strength has been attributed to a uniform distribution of fine rod-like precipitates of MgZn2 phase. The TRC and hot-rolled sheet also showed an exceptionally high stretch formability with a limiting dome height much larger than those of other Mg alloys.
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Magnesium Technology 2011 - Mechanical Properties and Microstructures of Twin Roll Cast Mg-2.4Zn-0.1Ag-0.1Ca-0.16Zr Alloy
Magnesium Technology 2011, 2011Co-Authors: Chamini Lakshi Mendis, Jun Ho Bae, Nack J. Kim, Kazuhiro HonoAbstract:In our previous study, we reported that the additions of 0.1 at.% Ag and 0.1 at.% Ca to Mg-2.4Zn-0.16Zr (at.%) alloy enhanced the age hardening response, and extruded alloy showed Tensile Yield Strength of 325 MPa with the T6 heat treatment. Considering its excellent age hardenability, we attempted to develop high Strength sheets from the alloy by twin-roll casting (TRC). TRC sheet of 2 mm in thickness were hot rolled to −1.2 mm. The TRC Mg-2.4Zn-0.1Ag-0.1Ca-0.16Zr alloy sheet showed Tensile Yield Strength of ~ 320MPa and an elongation to failure of 17% after T6 heat treatment. EBSD study indicated the average grain size is ~ 18±2.5μm and the grains have a weak basal texture. TEM, showed a uniform distribution of ~5 nm diameter MgZn2 phase. The high Yield Strength was attributed to the dispersion of rod-like precipitates.
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Precipitation-hardenable Mg–2.4Zn–0.1Ag–0.1Ca–0.16Zr (at.%) wrought magnesium alloy
Acta Materialia, 2008Co-Authors: Champake Mendis, Teruaki Honma, Kazuki Ohishi, Y. Kawamura, Shigeharu Kamado, Kazuhiro HonoAbstract:A new precipitation-hardenable wrought magnesium alloy based on the Mg–Zn system with an excellent combination of high Tensile Yield Strength, good ductility and low Tensile-compression anisotropy has been developed. The Mg–2.4Zn–0.1Ag–0.1Ca(–0.16Zr) (at.%) alloys show significantly higher age-hardening responses compared to that of the binary Mg–2.4Zn alloy due to the increased number density and refinement of rod-like MgZn2 precipitates. The addition of Zr to the Mg–2.4Zn–0.1Ag–0.1Ca alloy resulted in a significant refinement of the grain size. A high number density of precipitates was observed in the Mg–2.4Zn–0.1Ag–0.1Ca–0.16Zr alloy in both the as-extruded condition and following isothermal ageing at 160°C. The Tensile Yield Strength of the as-extruded and aged alloys was 289 and 325MPa, with an elongation of 17% and 14%, respectively. These alloys show relatively low compression and Tensile anisotropy. The origins of these unique mechanical properties are discussed based on the detailed microstructural investigation.
Xinping Zhang - One of the best experts on this subject based on the ideXlab platform.
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Contradictory Feature Size Effects in the Tensile Yield Strength of Cu Sheets Produced Using Different Sequences Involving Annealing, Rolling, and Grinding
Journal of Materials Engineering and Performance, 2018Co-Authors: Xiaofei Zhan, Xinping Zhang, X. H. DongAbstract:The feature size effect is significant research interest in the field of microforming. It is assumed that the size effect is influenced by the material preparation process. To verify this, the feature size effects associated with the Tensile Yield Strength of Cu sheets with thicknesses ranging from 100 to 200 μm, produced using different sequences involving annealing, rolling, and grinding, were studied. Differing feature size effects were observed in the Cu specimens, and it was confirmed that the size effect was indeed influenced by the specimen preparation sequence. The Tensile Yield Strengths of the annealed–ground–rolled and annealed–rolled specimens increased as the specimen thicknesses decreased. However, an opposing size effect was observed in the case of the annealed–rolled–annealed, annealed–ground, and annealed–rolled–ground specimens. The reduction ratio did not alter the trend associated with the size effect, but influenced the intensity of the size effect. It is believed that the reinforcement and erosion of the surface-hardened layer introduced during rolling resulted in the contradictory results.
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effects of extrusion parameters on Tensile properties of magnesium alloy tubes fabricated via hydrostatic extrusion integrated with circular ecap
Materials & Design, 2016Co-Authors: Renshu Yuan, Hongming Cai, Lei Zhao, Xinping ZhangAbstract:Abstract To meet the need for high Strength tubes for various industrial applications, a new method, known as hydrostatic extrusion integrated with circular equal channel angular pressing (HECCAP), was proposed for the fabrication of AZ80 magnesium alloy tubes. Small diameter billets could be extruded into tubes of larger diameters using this method. The effects of the extrusion ratio (ER) and the conical mandrel angle (CMA) on the microstructure and Tensile properties of the AZ80 magnesium alloy tube were investigated. The HECCAP-treated alloys exhibited a partial dynamically recrystallized microstructure. More shear zones formed inside of these grains, and a higher recrystallization grain volume fraction were presented in the alloy after HECCAP treatment with a larger ER or CMA values. The Tensile Yield Strength, ultimate Tensile Strength, and elongation percent increased as ER and CMA also increase. The highest ultimate Tensile Strength, Tensile Yield Strength and elongation were 335 MPa, 308 MPa, and 7.2%, respectively, at an ER of 2.77 and CMA of 120°. A formula was proposed to calculate the total generated plastic strain after HECCAP, which increased with increasing ER and CMA.
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Size effects on Tensile Strength of aluminum–bronze alloy at room temperature
Materials & Design, 2015Co-Authors: Fei Chen, X. H. Dong, Chen Shan, X.t. Hong, Xinping ZhangAbstract:Abstract Variations in Tensile Yield Strength of annealed CuAl7 copper alloy were investigated. Both grain and feature size effects could be observed. Statistical analysis revealed that the grain size effect was greater than the feature size effect. The grain size effect on the Tensile Yield Strength of the alloy was very significant. The feature size effect was very significant or significant when the specimen thickness was no more than 0.50 mm, while the effect was insignificant or completely absent when the specimen thickness was greater than 0.50 mm. In addition to grain size d and specimen thickness t , the t / d ratio of the specimen can also affect the Tensile Yield Strength. The Tensile Yield Strength of the alloy was almost a constant when the t / d ratio was greater than a critical value (approximately 21). Otherwise, the Strength tended to increase with an increasing value of t / d , except for the specimen with a thickness of 0.25 mm. The size effects on the Tensile Strength of the CuAl7 copper alloy were compared with the effects on the compression Strength. It was found that the size effect intensity on the compression Yield Strength was greater than that on the Tensile Yield Strength.
Rajarshi Banerjee - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Tensile Yield Strength in laser additively manufactured Al0.3CoCrFeNi high entropy alloy
Materialia, 2020Co-Authors: Mohan Sai Kiran Kumar Yadav Nartu, Stephane Gorsse, Talukder Alam, Sriswaroop Dasari, Srinivas Aditya Mantri, Hector Siller, Narendra Dahotre, Rajarshi BanerjeeAbstract:A precipitation Strengthenable high entropy alloy (HEA), Al0.3CoCrFeNi, was processed via laser-based additive manufacturing (AM), using the laser engineered net shaping (LENS) process. The as LENS processed HEA exhibited twice the Tensile Yield Strength, as compared to the conventionally arc-melted and solution treated HEA of the same composition, with a Tensile ductility greater than 20%. Subsequent heat-treatments of the AM HEA alloy led to further enhancement of the Yield Strength while maintaining good Tensile ductility. The microstructure of these AM alloys was investigated by coupling transmission electron microscopy (TEM) and atom probe tomography (APT). The near doubling of the Yield Strength in case of the as AM processed HEA samples, which were devoid of second phase intermetallic precipitates, has been rationalized based on the formation of nanometer-scale Al–Ni rich solute clusters due to the re-heating of the deposited layers during AM. The enhanced Yield Strength due to these solute clusters has been estimated using a simple cluster-dislocation interaction model involving the coherency strain fields of these nano-clusters. The even higher Yield Strength in case of the heat-treated AM HEA samples has been quantitatively rationalized employing precipitation Strengthening models, based on nanometer scale L12 (gamma prime) precipitates.
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Tensile Yield Strength of a single bulk al0 3cocrfeni high entropy alloy can be tuned from 160 mpa to 1800 mpa
Scripta Materialia, 2019Co-Authors: Bharat Gwalani, Stephane Gorsse, Deep Choudhuri, Yufeng Zheng, Rajiv S. Mishra, Rajarshi BanerjeeAbstract:Abstract While there have been multiple recent reports in the literature of exceptional combinations of Yield Strength and ductility in high entropy alloys, there have been no reports discussing the extraordinary tunability of the mechanical properties in the same alloy in these systems. This paper shows that the Tensile Yield-Strength of a single Al 0.3 CoCrFeNi high entropy alloy (or complex-concentrated alloy), can be enhanced from 160 MPa to over 1800 MPa (1.8 GPa), a 1025% increase, via microstructural engineering enabled by thermo-mechanical processing of the bulk alloy. Such Strength variations for the same composition are unprecedented in any other class of alloys.
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Tensile Yield Strength of a single bulk Al0.3CoCrFeNi high entropy alloy can be tuned from 160 MPa to 1800 MPa
Scripta Materialia, 2019Co-Authors: Bharat Gwalani, Stephane Gorsse, Deep Choudhuri, Yufeng Zheng, Rajiv Mishra, Rajarshi BanerjeeAbstract:While there have been multiple recent reports in the literature of exceptional combinations of Yield Strength and ductility in high entropy alloys, there have been no reports discussing the extraordinary tunability of the mechanical properties in the same alloy in these systems. This paper shows that the Tensile Yield-Strength of a single Al0.3CoCrFeNi high entropy alloy (or complex-concentrated alloy), can be enhanced from 160 MPa to over 1800 MPa (1.8 GPa), a 1025% increase, via microstructural engineering enabled by thermo-mechanical processing of the bulk alloy. Such Strength variations for the same composition are unprecedented in any other class of alloys.
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Spark Plasma Sintering (SPS) of Carbon Nanotube (CNT) / Graphene Nanoplatelet (GNP)-Nickel Nanocomposites: Structure Property Analysis
Advanced Composites for Aerospace Marine and Land Applications II, 2016Co-Authors: Tushar Borkar, Soon H. Hong, Thomas Scharf, Jaimie Tiley, Hamidreza Mohseni, Junyeon Hwang, Rajarshi BanerjeeAbstract:Carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) are attractive reinforcements for lightweight and high Strength metal matrix composites due to their excellent mechanical and physical properties. The CNT/Ni (DM) nanocomposites exhibiting a Tensile Yield Strength of 350 MPa (about two times that of nickel ∼ 160 MPa) and an elongation to failure ∼ 30%. In contrast, CNT/Ni (MLM) exhibited substantially higher Tensile Yield Strength (∼ 690 MPa) but limited ductility with an elongation to failure ∼ 8%. GNP/Nickel nanocomposites were also processed via DM followed by SPS consolidation. The Ni-1vol%GNP nanocomposite exhibited the best balance of properties in terms of Strength and ductility. The enhancement in the Tensile Strength (i.e. 370 MPa) and substantial ductility (∼ 40%) of Ni-1vol%GNP nanocomposites was achieved due to the combined effects of grain refinement, homogeneous dispersion of GNPs in the nickel matrix, and well-bonded Ni-GNP interface effectively transfers stress across metal-GNP interface during Tensile deformation.
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Excellent Strength–ductility combination in nickel-graphite nanoplatelet (GNP/Ni) nanocomposites
Journal of Alloys and Compounds, 2015Co-Authors: Tushar Borkar, Soon H. Hong, Jaimie Tiley, Hamidreza Mohseni, Junyeon Hwang, Thomas W. Scharf, Rajarshi BanerjeeAbstract:Abstract While multiple recent reports have demonstrated enormous enhancements in Yield Strength in metal matrix nanocomposites reinforced with carbon nanotubes and graphite nanoplatelets (GNP), such composites typically exhibit drastic reductions in Tensile ductility. Mechanical mixing of nickel (Ni) powders and GNP powders, followed by spark plasma sintering (SPS), has been used to develop a new class of GNP/Ni nanocomposites that exhibit huge enhancements in Tensile Yield Strength while preserving good ductility. Thus, a Ni-1GNP (1 vol.% GNP) nanocomposite exhibited a Tensile Yield Strength of 370 MPa (about 2.5 times of SPS processed monolithic nickel ∼160 MPa) and an elongation to failure ∼ 40%. Interestingly, while a higher volume fraction of GNPs, such as Ni-2.5GNP (2.5 vol.% GNP) exhibited an enhancement in Tensile Yield Strength due to grain refinement, there was a significant reduction in ductility ∼10%, primarily due to agglomeration of GNPs. The enhancement in the Tensile Strength and ductility of the Ni-1GNP nanocomposite can be attributed to combined effect of homogeneous dispersion of GNPs and grain refinement, the relative influence of each of these effects has been quantitatively assessed in this paper. Additionally, the strong metal-GNP interfacial bonding helps effectively transfer load across the GNP/metal interface during Tensile deformation.
Chamini Lakshi Mendis - One of the best experts on this subject based on the ideXlab platform.
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Magnesium Technology 2011 - Mechanical Properties and Microstructures of Twin Roll Cast Mg-2.4Zn-0.1Ag-0.1Ca-0.16Zr Alloy
Magnesium Technology 2011, 2011Co-Authors: Chamini Lakshi Mendis, Jun Ho Bae, Nack J. Kim, Kazuhiro HonoAbstract:In our previous study, we reported that the additions of 0.1 at.% Ag and 0.1 at.% Ca to Mg-2.4Zn-0.16Zr (at.%) alloy enhanced the age hardening response, and extruded alloy showed Tensile Yield Strength of 325 MPa with the T6 heat treatment. Considering its excellent age hardenability, we attempted to develop high Strength sheets from the alloy by twin-roll casting (TRC). TRC sheet of 2 mm in thickness were hot rolled to −1.2 mm. The TRC Mg-2.4Zn-0.1Ag-0.1Ca-0.16Zr alloy sheet showed Tensile Yield Strength of ~ 320MPa and an elongation to failure of 17% after T6 heat treatment. EBSD study indicated the average grain size is ~ 18±2.5μm and the grains have a weak basal texture. TEM, showed a uniform distribution of ~5 nm diameter MgZn2 phase. The high Yield Strength was attributed to the dispersion of rod-like precipitates.
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Microstructures and Tensile properties of a twin roll cast and heat-treated Mg-2.4Zn-0.1Ag-0.1Ca-0.1Zr alloy
Scripta Materialia, 2011Co-Authors: Chamini Lakshi Mendis, Jun Ho Bae, Nack J. Kim, Kazuhiro HonoAbstract:An Mg–2.4Zn–0.1Ag–0.1Ca–0.1Zr alloy sheet, with a Tensile Yield Strength of 316 MPa, an ultimate Tensile Strength of 342 MPa and an elongation of 17%, has been processed by twin roll casting (TRC), hot rolling and heat treatment. The high Yield Strength has been attributed to a uniform distribution of fine rod-like precipitates of MgZn2 phase. The TRC and hot-rolled sheet also showed an exceptionally high stretch formability with a limiting dome height much larger than those of other Mg alloys.
Shigeharu Kamado - One of the best experts on this subject based on the ideXlab platform.
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Microstructure evolution and mechanical properties of as-extruded Mg-Gd-Y-Zr alloy with Zn and Nd additions
Materials Science and Engineering: A, 2018Co-Authors: Jian Meng, X. Zhang, Shigeharu KamadoAbstract:Abstract The microstructure evolution and mechanical properties of as-extruded Mg-11.5Gd-4.5Y-0.3Zr (wt%) alloy with Zn and Nd additions were investigated. The addition of Zn inhibits the dynamic recrystallization (DRX) due to the presence of the long-period stacking ordered (LPSO) phase. The addition of Nd promotes the precipitation of the Mg5RE (RE: rare earth) phase. The existence of the densely distributed Mg5RE phase before hot extrusion promotes the DRX in subsequent hot extrusion process and leads to grain refinement. The increase in the number of Mg5RE phase particles degrades the mechanical properties of the resultant alloy. After hot extrusion, the studied alloys exhibit a bimodal microstructure consisting of fine dynamic recrystallized (DRXed) grains of several microns and strongly textured course un-DRXed grains. The as-extruded Mg-11.5Gd-4.5Y-1.5Zn-0.3Zr alloy exhibits an excellent balance of Strength and ductility (Tensile Yield Strength of 371 ± 3.0 MPa and elongation of 7.2 ± 0.8%). The alloy Strengthening is attributed to the bimodal microstructure, the Mg5RE and LPSO phases, and the basal texture. The Tensile Yield Strength of the as-extruded Mg-11.5Gd-4.5Y-1.5Zn-0.3Zr alloy can be further increased to 425 ± 2.5 MPa by precipitation hardening with the T5 treatment.
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Precipitation-hardenable Mg–2.4Zn–0.1Ag–0.1Ca–0.16Zr (at.%) wrought magnesium alloy
Acta Materialia, 2008Co-Authors: Champake Mendis, Teruaki Honma, Kazuki Ohishi, Y. Kawamura, Shigeharu Kamado, Kazuhiro HonoAbstract:A new precipitation-hardenable wrought magnesium alloy based on the Mg–Zn system with an excellent combination of high Tensile Yield Strength, good ductility and low Tensile-compression anisotropy has been developed. The Mg–2.4Zn–0.1Ag–0.1Ca(–0.16Zr) (at.%) alloys show significantly higher age-hardening responses compared to that of the binary Mg–2.4Zn alloy due to the increased number density and refinement of rod-like MgZn2 precipitates. The addition of Zr to the Mg–2.4Zn–0.1Ag–0.1Ca alloy resulted in a significant refinement of the grain size. A high number density of precipitates was observed in the Mg–2.4Zn–0.1Ag–0.1Ca–0.16Zr alloy in both the as-extruded condition and following isothermal ageing at 160°C. The Tensile Yield Strength of the as-extruded and aged alloys was 289 and 325MPa, with an elongation of 17% and 14%, respectively. These alloys show relatively low compression and Tensile anisotropy. The origins of these unique mechanical properties are discussed based on the detailed microstructural investigation.
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Mechanical Properties of Mg-Y-Zn Alloy Processed by Equal-Channel-Angular Extrusion
MATERIALS TRANSACTIONS, 2003Co-Authors: Hiroyuki Watanabe, Shigeharu Kamado, Toshiji Mukai, Yo Kojima, Kenji HigashiAbstract:Fine-grained WZ73 magnesium alloy with the grain size of 1.6 μm was produced by Equal-Channel-Angular Extrusion. The material exhibited Tensile Yield Strength of 293 MPa, Tensile Strength of 350 MPa and relatively large elongation of 18% at room temperature. The Yield Strength was almost unchanged up to 473 K. In addition, large superplastic elongation of over 300% was obtained at a temperature of 673 K.
