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Numerical simulation of Failure Behaviors of CFRP laminates on Hashin model coupled with cohesive elements

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Numerical simulation of Failure Behaviors of CFRP laminates ...

2018 International Conference on Advanced materials, Intelligent Manufacturing and Automation, AMIMA 2018

作者： Huang, Hongbo Ma, Xu Qiao, Jingwen Yanhong, Ding School of Material Science and Engineering Tianjin University of Technology Tianjin300384 China Tianjin Engineering Center of Near-Net-Shape Forming Technology for Metallic Materials Tianjin300384 China School of Electrical and Electronic Engineering Tianjin Key Laboratory of Film Electronic and Communication Devices Tianjin University of Technology Tianjin300384 China

The failure modes of carbon fiber reinforced composites (CFRP) was investigated in this study. A method of combination of Hashin model and cohesive elements was proposed to predict failure behaviors in T300/PR319 and AS carbon/epoxy laminates by FE model, while executing three-point bending test. The result shows that there are differences between the response of two materials during bending test. Fiber compression and matrix tension in T300/PR319 and AS carbon/epoxy appears first relatively. Subsequently delamination occurs in AS carbon/epoxy as a result of cohesive elements. A evaluating method of measuring fracture process displacement was also proposed under new damage criterion. © Published under licence by IOP Publishing Ltd.

关键词： Failure (mechanical)

First-principles Calculations of Strengthening Compounds in Magnesium Alloy： A General Review

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Journal of materials Science & technology 2016年第12期32卷 1222-1231页

作者： Yong Liu Hui Ren Wen-Cheng Hu De-Jiang Li Xiao-Oin Zeng Ke-Gang Wang Jian Lu Key Laboratory of Near Net Forming of Jiangxi Province. Nanchang University Nanchang 330031 China National Engineering Research Center of Light Alloys Net Forming Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratories of Metal Matrix Composite Shanghai Jiao Tong University Shanghai 200240 China Mechanical and Aerospace Engineering Department Florida Institute of Technology Melbourne FL 32901 USA Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Hong Kong China Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research Institute 8 Yuexing 1st Road Shenzhen Hi-Tech Industrial Park Nanshon District Shenzhen China

First-principles computation methods play an important role in developing and designing new magnesium *** this article,we present an overview of the first-principles modeling techniques used in recent years to simulate ideal models of the structure of strengthening compounds in Mg *** typical Mg compounds,structural stability,mechanical properties,electronic structure and thermodynamic properties have been ***,the elastic anisotropies of these compounds are examined,which is highly correlated with the possibility of inducing ***,some heterogeneous nucleation interfaces investigated by first-principles method are *** of the theoretical results are compared with available experimental *** hope to illustrate that the first-principles computation can help to accelerate the design of new Mg-based materials and the development of materials genome *** problems and future directions in this research field are considered.

关键词： Magnesium alloy Strengthening compounds First-principles calculation Mechanical properties Thermodynamic properties

A New Method for Improving Static and High Frequency Magnetic Properties of Fe67Co18Si11B4Amorphous Alloy 10

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A New Method for Improving Static and High Frequency Magneti...

2023 10th International Conference on Advanced Manufacturing technology and materials Engineering, AMTME 2023

作者： Wang, Dongmeng Ding, Yanhong Ma, Xu Li, Yan School of Integrated Circuit Science and Engineering Tianjin Key Laboratory of Film Electronic and Communication Devices Tianjin University of Technology Tianjin300384 China School of Material Science and Engineering Tianjin Engineering Center of Near-Net-Shape Forming Technology for Metallic Materials Tianjin University of Technology Tianjin300384 China Co. Ltd Tianjin300385 China

Rapidly quenched ribbons with a composition of Fe67Co18Si11B4 have been investigated. Surface leveling on the ribbon-free surface leads to the decline of the interior stress of Fe67Co18Si11B4 amorphous alloy, making a decrease of coercivity and a great improvement of static magnetic properties. Free surface leveling treatment can improve the AC magnetic properties of the Fe67Co18Si11B4 amorphous alloy. In high frequency region 106 Hz 3 can be achieved after surface leveling. Free surface leveling is an attractive method to achieve improvements in both static and high frequency magnetic properties. © Published under licence by IOP Publishing Ltd.

关键词： Cobalt alloys

Preparation of Nano Al 3 Ti-Tib 2 -Aln-Tin/Al Inoculant Ribbons And its Effect On Microstructures and Properties Of Alznmgcu Alloys

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SSRN 2023年

作者： Wang, Qian Zhao, Jinman Cui, Chunxiang Wu, Dayong He, Peng Ma, Haikun Kang, Jie Dong, Huicong Su, Ru Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and Engineering Hebei University of Science and Technology Shijiazhuang050018 China Key Lab. for New Type of Functional Materials in Hebei Province School of Materials science and Engineering Hebei University of Technology Tianjin300130 China China International Engineering Consulting Corporation Beijing100048 China

The nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons which contain a large number of evenly distributed nano particles, such as Al3Ti (size about 300 nm),TiB2 (size about 100 nm), AlN (size about 150 nm) and TiN (size about 200 nm) were prepared by vacuum rapid quenching furnace to refine the AlZnMgCu alloys. The nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons showed excellent inoculant effect, which modified the dendrite crystals to equiaxed crystals and refined the grains from 122 ± 4 μm to 36 ± 5 μm by addition of 0.3 wt% nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons. In addition to nano Al3Ti and TiB2 particles, nano AlN and TiN particles also have a certain orientation relationship with α-Al, which suggest that these particles possess nucleation potency to α-Al. After inoculated by 0.3% nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons, the ultimate tensile strength, yield strength, and microhardnessof the AlZnMgCu alloys increased from 246 MPa, 79 MPa, and 112 HV to 319 MPa, 100 MPa, and 136 HV, increased by 29.7%, 26.6% and 21.4%, respectively. © 2023, The Authors. All rights reserved.

关键词： Nanoparticles

Development of Nb-Based Alloy Membranes with Improved Resistance to Corrosion by H2s

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SSRN 2023年

作者： Yan, Erhu Zhang, Shuo Liu, Wei Zhang, Kexiang Huang, Guanzhong Jia, Limin Tao, Lizhen Chen, Hongfei Bai, Jinwang Chu, Hailiang Zou, Yongjin Zhang, Huanzhi Xu, Fen Sun, Lixian Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology Guilin541004 China Hebei Key Laboratory of Material Near-Net Forming Technology Hebei University of Science and Technology Shijiazhuang050018 China Department of Energy Materials and Telecommunications INRS-EMT QuebecJ3X 1S2 Canada

At present, the interest in non-Pd hydrogen permeation membranes mainly focuses on group 5B metals (Nb, V, Ta) and their alloys. To solve the problem of easy oxidation and weak dissociation of hydrogen molecules, a "Pd catalytic layer" needs to be deposited on the membrane surface. Due to its limited stability towards sulfur, issues of irreversible poisoning by sulfur compounds must be addressed. To this end, Pd-, Pd65Ag35-, Pd90Cu10-, Pd80Au20-, and Pd55Ag35Au10-coated Nb30Hf35Co35 membranes were firstly synthesised by magnetron sputtering, and their hydrogen permeation behaviour in pure H2 and/or in different H2/H2S mixtures for up to 1000 ppm at 673 K were evaluated. At these conditions, the permeabilities of the Pd-coated membranes decrease rapidly with increasing the H2S concentration and cannot recover after removal of H2S from the feed mixtures. In comparison, the Pd-Ag-containing membrane greatly increases the pure H2 permeability, whereas the membrane doped with Au can effectively improve the response to H2S. Specifically, the Pd65Ag35-coated membrane shows the highest pure H2 permeability, but it loses maximum permeability value on exposure to H2/H2S feed mixtures. In contrast, Pd80Au20-containing membranes exhibit good tolerance of H2S poisoning and displayed a high fractional recovery (~ 83%) of initial H2 permeability. The degradation of permeability for Pd- or Pd65Ag35-coated membranes after the H2S exposure can be ascribed to the deterioration of the structure caused by the possible formation of bulk Pd4S, which has been corroborated with EDS analysis, XRD, and XPS after testing. Finally, to improve both permeability and chemical tolerance, a Pd55Ag35Au10-coated membrane was successfully fabricated, and it possesses excellent comprehensive performance with respect to the permeability and H2S response. At 120 ppm H2S in the feed, the H2 flux equals ca. 43% of its original value at 673 K and can be stable for at least 166 hours. Bulk sulfides did not fo

关键词： Sulfur compounds

Atomic Simulations on the Deformation Mechanisms in Nano-Crystalline Ni-Based Superalloy Based on Grain Size, Temperature and Strain Rate

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SSRN 2022年

作者： Dong, Huicong Xu, Tianhao Ning, Tianyang Liu, Meng Wu, Dayong Ma, Haikun Feng, Zhihao Narayanaswamy, Balaji Su, Ru Hebei Key Laboratory of Material Near-net Forming Technology Hebei Engineering Laboratory of Aviation Lightweight Composite Materials and Processing Technology School of Materials Science and Engineering Hebei University of Science and Technology Hebei Shijiazhuang050000 China AVIC Shangda Superalloy Materials Co. Ltd Hebei Xingtai054800 China School of Engineering Deakin University Geelong Australia

Molecular Dynamic (MD) simulations were used to investigate the tensile properties of nanocrystalline Ni-based superalloy at different grain sizes (6.54~20 nm), temperatures (300~1000 K) and strain rates (1×107~1×109 s-1). Results indicate that plastic deformation of nanocrystalline Ni-based superalloy was governed by stacking faults and FCC-to-HCP martensitic phase transformation, which was significantly different from twinning-dominated plastic deformation in nanocrystalline Ni. Nevertheless, the conventional Hall-Petch breakdown occurred at a critical grain size in both nanocrystalline Ni and Ni-based superalloy. Moreover, flow stress and Young’s modulus were both strongly affected by temperature and strain rate. Furthermore, an increase in temperature can accelerate GB diffusion and GB migration. And, GB diffusion and GB migration were the main plastic deformation mechanisms at higher strain rates. The current study provides an atomic perspective on the deformation process and mechanisms in nanocrystalline Ni-based superalloy, as well as new perspectives on designing novel superalloys with excellent mechanical properties. © 2022, The Authors. All rights reserved.

关键词： Strain rate

Investigation on Fatigue Failure of Split-Sleeve Cold Expansion Holes of 7075-T651 Aluminum Alloy

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SSRN 2023年

作者： Su, Ru Li, Jinyu Liu, Weiguang Xu, Changzhou Gao, Lijie Liang, Xueze Wu, Dayong Huang, Xin Dong, Huicong Ma, Haikun Hebei Key Laboratory of Material Near-net Forming Technology School of Materials Science and Engineering Hebei University of Science and Technology Shijiazhuang050018 China Shijiazhuang Haishan Industrial Development Corporation Shijiazhuang050208 China Oriental Bluesky Titanium Technology Co. LTD Yantai264670 China

7075-T6 is widely used in the fabrication of aircraft structural components, the majority of which are joined and assembled through hole structures. However, the geometric discontinuity near the fastener holes facilitates stress concentration and makes the joints susceptible to crack initiation and fatigue failure. It is essential to enhance the hole structure's fatigue resistance. In this work, the factors affecting the split-sleeve cold expansion on the fatigue behavior of fastener holes of 7075-T651 are studied based on the compressive residual stress, microstructure, surface roughness, and fatigue fracture. Results revealed that the residual stress curve along the hole axis shows a 'hook' shape while the tangential residual stress distribution around the hole is nonaxisymmetric, which is the main reason for the improved fatigue life of the specimens. The cold expansion causes sub-grain refinement near the hole wall, increasing the surface micro-hardness and improving the fatigue life. The main origin of the fatigue for cold expansion specimens is initiated at the corner of the hole on the mandrel inlet side. The constituent particles and microstructure after expansion are important factors affecting fatigue performance, and the presence of iron-bearing particles has a significant impact on service life reduction. © 2023, The Authors. All rights reserved.

关键词： Residual stresses

Atomic Simulations of Crack Propagation in Ni-Al Binary Single Crystal Superalloy with a Central Crack

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SSRN 2024年

作者： Yang, Liu Dong, Huicong Wu, Dayong Ma, Haikun Feng, Zhihao He, Peng Narayanaswamy, Balaji You, Baocai Wang, Qian Su, Ru Hebei Key Laboratory of Material Near-net Forming Technology Hebei Engineering Laboratory of Aviation Lightweight Composite Materials and Processing Technology School of Materials Science and Engineering Hebei University of Science and Technology Hebei Shijiazhuang050000 China China International Engineering Consulting Corporation Beijing100000 China Deakin University Australia Shenyang Aircraft Design Institute Shenyang110000 China

Nickel (Ni)-based single-crystal superalloys are of great importance in the aircraft industry due to their excellent mechanical properties, and cracks as unavoidable defects may affect the mechanical performances of materials dramatically. In this paper, large scale molecular dynamics (MD) simulations are carried out to understand the deformation mechanisms of Ni-based single crystal with a central crack under tension. Here, the effects of matrixes (g, g′ and g/g′), strain rates (1×109 s-1 ~ 3×109 s-1) and temperatures (300 K~ 900 K) on the role of crack propagation are considered. It is observed that dislocations and slip systems in the γ′ model are concentrated near the crack, resulting in the rapid expansion of dislocation, which leads to the fastest crack growth speed and early fracture. While the crack propagation rate of γ and γ/γ′ models are relatively slow,due to the combined action of the Lomer-Cottrell lock and stacking fault tetrahedron structure and Stair-rod dislocation, which hinders crack propagation. In addition, deformation at increased strain rates and/or reduced temperatures, lead to superior yield stress and Young′s modulus for models with a central crack at g/g′ interface. On the other hand, high temperature and high strain rate will promote crack propagation in the r phase, and the higher the strain rate and/or temperature, the faster the crack propagation speed will be. These results will enrich our understanding on the crack propagation and evolution mechanisms in Ni-based single crystal superalloy. © 2024, The Authors. All rights reserved.

关键词： Molecular dynamics

Effect of Single and Double Stage Homogenization Treatments on Microstructure and Properties of Wire + Arc Additively Manufactured 2319 Al Alloy

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SSRN 2024年

作者： Cao, Fenglei Gu, Yunfei Wang, Liwei Liu, Ying Chen, Shaohui Tian, Changjiang Liang, Zhimin Narayanaswamy, Balaji Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and Engineering Hebei University of Science and Technology Shijiazhuang050018 China Beijing Aeronautical Technology Research Center Beijing100076 China Shijiazhuang Haishan Industrial Development Co. Ltd. Shijiazhuang050208 China University of Sydney NSW2006 Australia

In this study, the effect of homogenization treatments (single and double stages) on the wire + arc additively manufactured (WAAM) 2319 Al alloy was analyzed. This involved an in-depth study on the diffusion and dissolution of eutectic phases using advanced characterization techniques (DSC, XRD, optical and electron microscopy). Homogenization treatment parameters (temperature and time) were determined based on DSC analyses. These parameters were later confirmed using homogenization kinetics calculations. A single-stage homogenization at 530℃/24h facilitated a full diffusion of the Al2Cu phase, but some eutectic phases remain undissolved at the grain boundaries. There is resulted in reduction of hardness, ultimate tensile strength and yield strength reduced by 26.0%, 28.5 and 28.8, respectively. A double-stage homogenization at 480℃/8h + 530℃/24h facilitated a full diffusion and dissolution of Al2Cu, resulting in an improvement of elongation (by 2.8%), while the hardness, ultimate tensile strength and yield strength was reduced by 28.7%, 28.3 and 26.2, respectively. Al2Cu phase at the grain boundaries was almost disappeared, with several Al2Cu particles being precipitated within the grain. The homogenization treatments eliminated the eutectic phase segregation formed during the additive manufacturing (AM) process, improved the homogeneity of the WAAM 2319 Al alloy microstructures at a compromise in the mechanical properties. © 2024, The Authors. All rights reserved.

关键词： Diffusion