Vietnam Journal of Mechanics最新文献

Application of small punch test to estimate mechanical behaviour of SUS304 austenitic stainless steel 应用小冲压试验评估 SUS304 奥氏体不锈钢的机械性能

Vietnam Journal of Mechanics Pub Date : 2024-06-11 DOI: 10.15625/0866-7136/20801

The Yen Doan, H. Pham

{"title":"Application of small punch test to estimate mechanical behaviour of SUS304 austenitic stainless steel","authors":"The Yen Doan, H. Pham","doi":"10.15625/0866-7136/20801","DOIUrl":"https://doi.org/10.15625/0866-7136/20801","url":null,"abstract":"The small punch test with an application of a relatively small specimen has recently become a reliable material mechanics testing method. In this study, the small punch test is set up based on the conventional mechanical testing machine for SUS304 stainless steel to evaluate the mechanical properties of SUS304 steel at different displacement rates of the punch in quasi-static loading condition in the case of with and without heat treatment. Although heat treatment has an insignificant effect on the microstructure and hardness of the material, the mechanical properties of the material in the small punch test are greatly reduced after heat treatment. Both cases with and without heat treatment have a similar tendency for the rate - sensitivity of the applied force - displacement curve. A higher value of force is applied to obtain the same value of displacement at a low displacement rate in the stable plastic deformation zone. Meanwhile, the maximum value of applied force is higher at a higher displacement rate in the stage that initiation of crack might appear. In the examined range of displacement rate, a positive rate - sensitivity of displacement at the maximum force. Therefore, a correlation between equivalent fracture strain and fracture toughness of the material can be achieved.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"4 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141357681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wave propagation in context of Moore–Gibson–Thompson thermoelasticity with Klein–Gordon nonlocality 具有克莱因-戈登非局域性的摩尔-吉布森-汤普森热弹性背景下的波传播

Vietnam Journal of Mechanics Pub Date : 2024-06-10 DOI: 10.15625/0866-7136/19728

Baljeet Singh

{"title":"Wave propagation in context of Moore–Gibson–Thompson thermoelasticity with Klein–Gordon nonlocality","authors":"Baljeet Singh","doi":"10.15625/0866-7136/19728","DOIUrl":"https://doi.org/10.15625/0866-7136/19728","url":null,"abstract":"Understanding plane and surface waves in elastic materials is crucial in various fields, including geophysics, seismology, and materials science, as they provide valuable information about the properties of the materials they travel through and can help in earthquake detection and analysis. In the present paper, the governing equations of Moore–Gibson–Thompson (MGT) thermoelasticity are modified in context of Klein–Gordon (KG) nonlocality. For linear, homogeneous and isotropic case, the governing equations in two-dimensions are solved to obtain the dispersion relations for possible plane waves. It is found that there exists one transverse and two coupled longitudinal waves in a two-dimensional model of MGT weakly nonlocal thermoelastic medium and the speeds of these plane waves are found to be dependent on KG nonlocal parameters. The coupled longitudinal waves are also found to be dependent on conductivity rate parameter. For linear, homogeneous and isotropic case, the governing equations in two-dimensions are also solved to obtain a Rayleigh wave secular equation at thermally insulated surface. For a numerical example of aluminium material, the speeds of transverse wave, coupled longitudinal waves and the Rayleigh wave are computed and graphically illustrated to visualize the effects of KG nonlocality parameters, conductivity rate parameter and the angular frequency on the wave speeds.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":" 35","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141366180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Size-dependent nonlinear bending of microbeams based on a third-order shear deformation theory 基于三阶剪切变形理论的微梁尺寸相关非线性弯曲理论

Vietnam Journal of Mechanics Pub Date : 2024-06-10 DOI: 10.15625/0866-7136/20702

N. Dang, Dinh Kien Nguyen, Cong Ich Le

{"title":"Size-dependent nonlinear bending of microbeams based on a third-order shear deformation theory","authors":"N. Dang, Dinh Kien Nguyen, Cong Ich Le","doi":"10.15625/0866-7136/20702","DOIUrl":"https://doi.org/10.15625/0866-7136/20702","url":null,"abstract":"In this paper, the size-dependent nonlinear bending of microbeams subjected to mechanical loading is studied using a finite element formulation. Based on the von Kármán nonlinear relationship and the third-order shear deformation theory, a size-dependent nonlinear beam element is derived by using the modified couple stress theory (MCST) to capture the microstructural size effect. The element with explicit expressions for the element vector of internal forces and tangent stiffness matrix is derived by employing the transverse shear rotation as a variable. Nonlinear bending of microbeams under different mechanical loading is predicted with the aid of Newton–Raphson iterative method. Numerical investigation shows that the derived element is efficient, and it is capable of giving accurate results by several elements. The obtained results reveal the importance of the micro-size effect on the nonlinear behavior of the microbeams, and the deflections are overestimated when the microstructural effect is ignored. The effects of the material length scale parameter, boundary conditions and loading type on the bending response of the microbeams are studied and highlighted.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"106 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141361449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of newly proposed hardening laws for structural steel rods 应用新提出的钢结构杆件淬火法则

Vietnam Journal of Mechanics Pub Date : 2024-06-04 DOI: 10.15625/0866-7136/20106

Van Nam Nguyen, Duy Triet Doan, Nhat-Phi Doan

{"title":"Application of newly proposed hardening laws for structural steel rods","authors":"Van Nam Nguyen, Duy Triet Doan, Nhat-Phi Doan","doi":"10.15625/0866-7136/20106","DOIUrl":"https://doi.org/10.15625/0866-7136/20106","url":null,"abstract":"In civil engineering, distinct mechanical properties and behaviors of structural steel rods necessitate a novel approach to material modeling. This study extends the application of recently proposed strain-hardening laws, originally developed for automotive sheet metals, to several structural steel rods (CB240-T and CB300-T). Standard uniaxial tensile tests are conducted for each examined material to obtain experimental stress-strain data. Various curve fitting methods are then employed to refine the parameters of the strain-hardening laws, enabling accurate representation of the steel rods mechanical behavior. Subsequently, these laws are implemented in Abaqus software for numerical simulation of uniaxial tensile tests, facilitating the analyses of material response under uniaxial tensile loading condition. Compared to the measured data, the predicted force-displacement curves are in good agreement with the measurements until the tail of the curves. The comparisons verify the ability and potential of the examined hardening law for studying the post-necking behavior of structural steels. The outcomes provide a framework for more precise characterization of structural steel materials.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"122 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141387415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exact receptance function of a tapered AFG beam with nonlinearly varying ratios of beam properties carrying concentrated masses 具有非线性变化梁特性比的锥形 AFG 梁的精确受力函数，承载集中质量

Vietnam Journal of Mechanics Pub Date : 2023-12-31 DOI: 10.15625/0866-7136/19697

Thao Thi Bich Dao, Khoa Viet Nguyen, Quang Van Nguyen

引用次数: 0

Proportional Topology Optimization algorithm with virtual elements for multi-material problems considering mass and cost constraints 考虑质量和成本约束的多材料问题虚拟元素比例拓扑优化算法

Vietnam Journal of Mechanics Pub Date : 2023-12-31 DOI: 10.15625/0866-7136/19613

Minh Tuan Tran, Minh Ngoc Nguyen

{"title":"Proportional Topology Optimization algorithm with virtual elements for multi-material problems considering mass and cost constraints","authors":"Minh Tuan Tran, Minh Ngoc Nguyen","doi":"10.15625/0866-7136/19613","DOIUrl":"https://doi.org/10.15625/0866-7136/19613","url":null,"abstract":"This paper presents an extension of the Proportional Topology Optimization (PTO) with virtual elements for multi-material problems with mass and cost constraints. In particular, the linear virtual element method (VEM) is constructed on unstructured polygonal meshes. The linear VEM is desirable in the sense that numerical integration is not explicitly required, significantly reducing the computational effort. Furthermore, the unstructured polygonal mesh naturally eliminates the issue of one-node connections encountered by the usual quadrilateral mesh. A feature of PTO is that it does not require sensitivity information, i.e., the derivative of the objective function with respect to design variables. Instead, the amount of material distributed into each element is determined proportionally to the contribution of that element to the objective function. For multi-material problems, the Ordered Solid Isotropic Material with Penalization (Ordered SIMP) technique is integrated into the PTO framework. Compared to other techniques for problems that involve multiple materials, Ordered SIMP has the advantage that computational cost does not depend on the number of materials. Furthermore, for the first time, the PTO approach is extended to consider two types of constraints: mass and cost simultaneously. The feasibility and efficiency of the proposed method are demonstrated via several benchmark examples and comparisons with the existing approach.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"53 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139130799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adhesive contact between two-dimensional anisotropic elastic bodies 二维各向异性弹性体之间的粘着接触

Vietnam Journal of Mechanics Pub Date : 2023-12-28 DOI: 10.15625/0866-7136/19700

Nguyen Dinh Duc, Nguyen Van Thuong

{"title":"Adhesive contact between two-dimensional anisotropic elastic bodies","authors":"Nguyen Dinh Duc, Nguyen Van Thuong","doi":"10.15625/0866-7136/19700","DOIUrl":"https://doi.org/10.15625/0866-7136/19700","url":null,"abstract":"Adhesion plays a vital role in the design of smart and intelligent high-tech devices such as modern optical, microelectromechanical, and biomedical systems. However, in the literature, adhesive contact is mostly considered for contact of rigid substrates and transversely isotropic and isotropic elastic materials. The composite materials are increasingly used in the mart and intelligent high-tech devices. Since the composite materials are generally anisotropic and contact bodies are all deformable, it is more practical to consider the adhesive contact of two anisotropic elastic materials. In this paper, an adhesive contact model of anisotropic elastic bodies is established, and the closed-form solutions for two-dimensional adhesive contact of two anisotropic elastic bodies are derived. The full-field solutions and the relation for the contact region and applied force are developed using the Stroh complex variable formalism, the analytical continuation method, and concepts of the JKR adhesive model. We will show that the frictionless contact of two anisotropic elastic materials is just a special case of the present contact problem, and its solutions can be obtained by setting the work of adhesion equal to zero. In addition, we also show that our present solutions are valid for the problems of indentation by a rigid punch on an elastic half-space through a proper placement of the contact radius and the corresponding material constant. Numerical results are provided to demonstrate the accuracy, applicability, and versatility of the developed solutions.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"44 28","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139151292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the velocity of droplet at steady state in contraction microchannels by numerical simulation 通过数值模拟研究收缩微通道中液滴的稳态速度

Vietnam Journal of Mechanics Pub Date : 2023-12-05 DOI: 10.15625/0866-7136/18918

Thanh Tung Nguyen, V. Hoang, D. Luu, Ngoc Hai Tran, M. Tran, Le Hung Toan Do

引用次数: 0

Micromechanical model to predict the effect of temperature on the behavior of unsaturated porous media 预测温度对非饱和多孔介质行为影响的微观力学模型

Vietnam Journal of Mechanics Pub Date : 2023-09-30 DOI: 10.15625/0866-7136/19023

Bao Viet Tran, Xavier Chateau

引用次数: 0

About the nonlinear vibration equation of the beam 关于梁的非线性振动方程

Vietnam Journal of Mechanics Pub Date : 2023-09-30 DOI: 10.15625/0866-7136/18189

Nguyen Van Khang, Nguyen Thi Van Huong, Nguyen Van Quyen, Pham Thanh Chung

引用次数: 0