The Experts below are selected from a list of 25611 Experts worldwide ranked by ideXlab platform
Deliang Zhang - One of the best experts on this subject based on the ideXlab platform.
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enhanced strength and toughness of bulk ultrafine grained cu by nacre inspired Lamellar Structure
Journal of Alloys and Compounds, 2020Co-Authors: Yuehuang Xie, Jun Wang, Mingwei Zhang, Mianmian Ruan, Jiamiao Liang, Roland E Loge, Deliang ZhangAbstract:Abstract An ultrafine grained (UFG) bulk Cu with a novel nacre-inspired Lamellar Structure containing nano-bridges and aligned nanopores at inter-Lamellar interfaces was fabricated by consolidation of a nanocrystal-attached ultrathin Cu flake powder by spark plasma sintering with a relatively lower pressure (50 MPa) followed by hot rolling. It was discovered that the bulk UFG Cu with such a novel Structure has both higher strength and higher toughness (static toughness) than its counterpart with a conventional UFG Structure, despite the latter has a perceived better metallurgical quality as evidenced by a lower content of pores. The formation mechanism of the nacre-inspired microStructure in bulk Cu and its correlation with strengthening and toughening mechanisms were illustrated.
Yunpeng Zhang - One of the best experts on this subject based on the ideXlab platform.
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a true change of nial cr mo eutectic Lamellar Structure during high temperature treatment
Journal of Alloys and Compounds, 2018Co-Authors: Lei Wang, Jun Shen, Guojun Zhang, Yunpeng ZhangAbstract:Abstract A true change of NiAl-Cr(Mo) eutectic Lamellar Structure during high temperature treatment is investigated at 1150 °C (≈0.8 T m ). The result indicates that the Lamellar Structure is instable, and the Lamellar Structure at the eutectic cell center possesses poorer stability compared to that at the eutectic cell boundary. The deep etching demonstrates that the pinching off and spheroidization of Cr(Mo) lamellae observed by mild etching are not true. A true case is that only local dissolution of Cr(Mo) lamellae (corresponding to pinching off) occurs. In particular, the observation way inclining 45° to growth direction could clearly verify that the spheroidization of Cr(Mo) lamellae does not occur, and actually the cylinderization of Cr(Mo) lamellae occurs. The relative instability mechanism is also discussed.
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microStructure fracture toughness and compressive property of as cast and directionally solidified nial based eutectic composite
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2016Co-Authors: Lei Wang, Jun Shen, Yunpeng ZhangAbstract:Abstract MicroStructure and room temperature mechanical property of as-cast and directionally solidified NiAl-Cr(Mo) eutectic composite were investigated by SEM, EDS, three point bending test and compression test. The microStructure of as-cast alloy consists of Cr(Mo) primary dendrites and equiaxed eutectic cells. For the directional solidification of liquid metal cooling technique (LMC), only the small quantity of Cr(Mo) primary dendrites appear in the beginning of solidification, and the fully and well-aligned Lamellar Structure parallel to the growth direction is obtained in the steady-state zone. However, the Cr(Mo) primary phase is always observed in the whole directional solidification of zone melted liquid metal cooling technique (ZMLMC), and the eutectic lamellas are disordered and not parallel to the growth direction in the steady-state zone. Compared to the ZMLMC alloys, the LMC alloy has the better room temperature fracture toughness and compressive property due to the well-aligned Lamellar Structure. Crack propagation and fracture surface are also observed to understand the fracture behavior.
Cunxu Wei - One of the best experts on this subject based on the ideXlab platform.
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different structural properties of high amylose maize starch fractions varying in granule size
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Canhui Cai, Z Wang, Lingshang Lin, Lingxiao Zhao, Jianmin Man, Cunxu WeiAbstract:Large-, medium-, and small-sized granules were separated from normal and high-amylose maize starches using a glycerol centrifugation method. The different-sized fractions of normal maize starch showed similar molecular weight distribution, crystal Structure, long- and short-range ordered Structure, and Lamellar Structure of starch, but the different-sized fractions of high-amylose maize starch showed markedly different structural properties. The amylose content, iodine blue value, amylopectin long branch-chain, and IR ratio of 1045/1022 cm(-1) significantly increased with decrease of granule size, but the amylopectin short branch-chain and branching degree, relative crystallinity, IR ratio of 1022/995 cm(-1), and peak intensity of Lamellar Structure markedly decreased with decrease of granule size for high-amylose maize starch. The large-sized granules of high-amylose maize starch were A-type crystallinity, native and medium-sized granules of high-amylose maize starch were CA-type crystallinity, and small-sized granules of high-amylose maize starch were C-type crystallinity, indicating that C-type starch might contain A-type starch granules.
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Different Structural Properties of High-Amylose Maize Starch Fractions Varying in Granule Size
2014Co-Authors: Canhui Cai, Z Wang, Lingshang Lin, Lingxiao Zhao, Jianmin Man, Cunxu WeiAbstract:Large-, medium-, and small-sized granules were separated from normal and high-amylose maize starches using a glycerol centrifugation method. The different-sized fractions of normal maize starch showed similar molecular weight distribution, crystal Structure, long- and short-range ordered Structure, and Lamellar Structure of starch, but the different-sized fractions of high-amylose maize starch showed markedly different structural properties. The amylose content, iodine blue value, amylopectin long branch-chain, and IR ratio of 1045/1022 cm–1 significantly increased with decrease of granule size, but the amylopectin short branch-chain and branching degree, relative crystallinity, IR ratio of 1022/995 cm–1, and peak intensity of Lamellar Structure markedly decreased with decrease of granule size for high-amylose maize starch. The large-sized granules of high-amylose maize starch were A-type crystallinity, native and medium-sized granules of high-amylose maize starch were CA-type crystallinity, and small-sized granules of high-amylose maize starch were C-type crystallinity, indicating that C-type starch might contain A-type starch granules
J Eckert - One of the best experts on this subject based on the ideXlab platform.
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deformation mechanisms to ameliorate the mechanical properties of novel trip twip co cr mo cu ultrafine eutectic alloys
Scientific Reports, 2017Co-Authors: Jeong Tae Kim, Sung Hwan Hong, Hae Jin Park, Y S Kim, Jinyoo Suh, J K Lee, Jongae Park, T Maity, J EckertAbstract:In the present study, the microstructural evolution and the modulation of the mechanical properties have been investigated for a Co-Cr-Mo (CCM) ternary eutectic alloy by addition of a small amount of copper (0.5 and 1 at.%). The microstructural observations reveal a distinct dissimilarity in the eutectic Structure such as a broken Lamellar Structure and a well-aligned Lamellar Structure and an increasing volume fraction of Co lamellae as increasing amount of copper addition. This microstructural evolution leads to improved plasticity from 1% to 10% without the typical tradeoff between the overall strength and compressive plasticity. Moreover, investigation of the fractured samples indicates that the CCMCu alloy exhibits higher plastic deformability and combinatorial mechanisms for improved plastic behavior. The improved plasticity of CCMCu alloys originates from several deformation mechanisms; i) slip, ii) deformation twinning, iii) strain-induced transformation and iv) shear banding. These results reveal that the mechanical properties of eutectic alloys in the Co-Cr-Mo system can be ameliorated by micro-alloying such as Cu addition.
Lei Wang - One of the best experts on this subject based on the ideXlab platform.
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a true change of nial cr mo eutectic Lamellar Structure during high temperature treatment
Journal of Alloys and Compounds, 2018Co-Authors: Lei Wang, Jun Shen, Guojun Zhang, Yunpeng ZhangAbstract:Abstract A true change of NiAl-Cr(Mo) eutectic Lamellar Structure during high temperature treatment is investigated at 1150 °C (≈0.8 T m ). The result indicates that the Lamellar Structure is instable, and the Lamellar Structure at the eutectic cell center possesses poorer stability compared to that at the eutectic cell boundary. The deep etching demonstrates that the pinching off and spheroidization of Cr(Mo) lamellae observed by mild etching are not true. A true case is that only local dissolution of Cr(Mo) lamellae (corresponding to pinching off) occurs. In particular, the observation way inclining 45° to growth direction could clearly verify that the spheroidization of Cr(Mo) lamellae does not occur, and actually the cylinderization of Cr(Mo) lamellae occurs. The relative instability mechanism is also discussed.
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microStructure fracture toughness and compressive property of as cast and directionally solidified nial based eutectic composite
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2016Co-Authors: Lei Wang, Jun Shen, Yunpeng ZhangAbstract:Abstract MicroStructure and room temperature mechanical property of as-cast and directionally solidified NiAl-Cr(Mo) eutectic composite were investigated by SEM, EDS, three point bending test and compression test. The microStructure of as-cast alloy consists of Cr(Mo) primary dendrites and equiaxed eutectic cells. For the directional solidification of liquid metal cooling technique (LMC), only the small quantity of Cr(Mo) primary dendrites appear in the beginning of solidification, and the fully and well-aligned Lamellar Structure parallel to the growth direction is obtained in the steady-state zone. However, the Cr(Mo) primary phase is always observed in the whole directional solidification of zone melted liquid metal cooling technique (ZMLMC), and the eutectic lamellas are disordered and not parallel to the growth direction in the steady-state zone. Compared to the ZMLMC alloys, the LMC alloy has the better room temperature fracture toughness and compressive property due to the well-aligned Lamellar Structure. Crack propagation and fracture surface are also observed to understand the fracture behavior.
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hydrogen bonded Lamellar network of pyromellitic acid pillared by 8 hydroxyquinoline
Chinese Journal of Chemistry, 2006Co-Authors: Lei Wang, Hong Zhang, Jingping Zhang, Feixue Gao, Ruimao Hua, Guangyuan ZhouAbstract:8-Hydroxyquinoline (8-q) salt of pyromellitic acid (benzene-1,2,4,5-tetracarboxylic acid, H(4)bta) forms robust Lamellar Structure where [H(2)bta](2-) anions build up sheets through strong hydrogen bonds in two dimensions and [H-8-q](+) cations act as pillars to afford an extended three dimensional network.
