Mechanics of Materials最新文献_第2页

Low-dose neutron irradiation effects on the elastoplastic deformation mechanisms of aluminum-doped gallium nitride under contact loading 低剂量中子辐照对接触加载下掺铝氮化镓弹塑性变形机制的影响

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-15 DOI: 10.1016/j.mechmat.2024.105180

{"title":"Low-dose neutron irradiation effects on the elastoplastic deformation mechanisms of aluminum-doped gallium nitride under contact loading","authors":"","doi":"10.1016/j.mechmat.2024.105180","DOIUrl":"10.1016/j.mechmat.2024.105180","url":null,"abstract":"<div><div>The elastoplastic deformation mechanisms of irradiated aluminum (Al)-doped gallium nitride (GaN) under contact loading are investigated in this work using the nanoindentation simulations, which is of great significance for understanding the mechanical properties of the Al-doped GaN and guiding the design of durable and high-performance GaN-based devices. The mechanical behaviors of the Al-doped GaN with different doping concentrations are analyzed, including the indentation hardness, Young's modulus, elastic recovery rates, phase transformations, and stress distribution. It is found that Al doping increases their hardness, Young's modulus, and elastic recovery rates, and leads to an enlargement of the phase transformation regions, which is dominated by the high coordination number (CN) phase transformations. Furthermore, the effects of low-dose neutron irradiation on their elastoplastic deformation mechanisms are studied by triggering cascade collisions within the structure. When subjected to such irradiation, structural changes occur in the Al-doped GaN, their indentation hardness, Young's modulus, and elastic recovery rates increase remarkably, and its phase transformation mechanism is changed remarkably. The dislocation behaviors of the doped and undoped GaN are different under neutron irradiation. This study is important for capturing the mechanical stability and integrity of Al-doped GaN in an irradiation environment, as well as developing GaN-based devices with superior irradiation resistance.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Damage quantification in concrete under uniaxial compression using microcomputed tomography and digital volume correlation with consideration of heterogeneity 利用微计算机断层扫描和数字体积相关技术量化单轴压缩下混凝土的损伤，并考虑异质性

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-11 DOI: 10.1016/j.mechmat.2024.105178

引用次数: 0

Influence of shot-peening on the self-heating behavior and fatigue properties of 300M steel 喷丸强化对 300M 钢自热行为和疲劳性能的影响

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-09 DOI: 10.1016/j.mechmat.2024.105174

{"title":"Influence of shot-peening on the self-heating behavior and fatigue properties of 300M steel","authors":"","doi":"10.1016/j.mechmat.2024.105174","DOIUrl":"10.1016/j.mechmat.2024.105174","url":null,"abstract":"<div><div>Shot peening is an established cold working process used to introduce residual compressive stresses on a surface and is extensively studied using conventional fatigue tests. However, it has not been widely studied using the self-heating method. Specifically, the heterogeneity of the dissipation field has not been estimated, with only an average approach being used. Previous investigations in the case of 300M steel demonstrated that the effect of shot peening on the high cycle fatigue properties can be either beneficial or detrimental. This study proposes to apply the self-heating method on polished 300M and to investigate the effect of mean stress and shot peening on the dissipation behavior. A modified self-heating model is proposed and calibrated for 300M steel. Combined with residual stress profiles, a method to compute and determine the shot peening effect on self-heating behavior through single point surface measurements is proposed. Application on 300M steel shows excellent results, the over-dissipation being mainly due to the sub-surface compressive residual stresses. The self-heating method has proven useful to quickly estimate fatigue properties of polished 300M steel. Based on the understanding of the self-heating curve of shot peened 300M steel, a quantification of shot-peening effect on fatigue limit is discussed.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of the strain rate and stretch level dependent behavior of elastomeric nanocomposites in complex uniaxial tests under finite strains 有限应变下复杂单轴试验中弹性纳米复合材料的应变率和拉伸水平相关行为研究

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-09 DOI: 10.1016/j.mechmat.2024.105177

{"title":"Investigation of the strain rate and stretch level dependent behavior of elastomeric nanocomposites in complex uniaxial tests under finite strains","authors":"","doi":"10.1016/j.mechmat.2024.105177","DOIUrl":"10.1016/j.mechmat.2024.105177","url":null,"abstract":"<div><div>The mechanical behavior of elastomeric nanocomposites in experiments with nested stress-strain cycles and in cyclic tests with increasing strain amplitude was considered. In the proposed testing procedures, long time stops at each stage of the change in loading direction were of great importance. This revealed two significant features of the behavior of elastomeric nanocomposites that have received little attention. It was shown that material softening (the Mullins effect) should be considered not only in the elastic part of the Cauchy stress tensor, but also in its dissipative part. The second peculiarity was the difference between the characteristic relaxation time at loading and the characteristic relaxation time at unloading observed in the experiments.</div><div>This paper focuses on the behavior of highly-filled elastomeric materials based on different matrices (styrene-butadiene rubber (SBR) and nitrile-butadiene rubber (NBR)) and with different concentrations of carbon black (CB) or a combination of two fillers (CB and purified multi-walled carbon nanotubes (MWCNTs)).</div><div>A mathematical model of the viscoelastic behavior of elastomeric nanocomposites under finite strains is proposed. It takes into account the peculiarities of the behavior of highly filled elastomers observed in the experiments. The specificity of the model consists in a new variant of the form of the free energy potential. It is shown that the new model satisfies the thermodynamic inequality, which is a consequence of the first law of thermodynamics and the second law in the form of the Clausius-Duhem inequality. A good agreement between theoretical calculations and experimental data was obtained.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A cooperative relaxation model with two physical parameters for investigating the temperature and cure dependence of relaxation mechanisms in resins 具有两个物理参数的协同松弛模型，用于研究树脂中松弛机制的温度和固化依赖性

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-05 DOI: 10.1016/j.mechmat.2024.105172

{"title":"A cooperative relaxation model with two physical parameters for investigating the temperature and cure dependence of relaxation mechanisms in resins","authors":"","doi":"10.1016/j.mechmat.2024.105172","DOIUrl":"10.1016/j.mechmat.2024.105172","url":null,"abstract":"<div><div>Modeling the relaxation properties of resin matrix during cure plays an important role in predicting process-induced residual stresses and final distortions of resin-based composites. This paper develops a physical characterization model, which explains the temperature and cure-degree dependence of relaxation behaviors in terms of the size of cooperatively rearranging region, and special emphasis is placed on investigating the general physical mechanism of cure degree affecting the relaxation properties. In this model, the relaxation time is governed by a modified Adam-Gibbs equation, which is extended here to include the cure dependence. In addition, the relaxation modulus is modeled in a chemo-rheologically simple manner (CSM) based on the free volume theory. Material characterization is carried out using experimental data of two typical resins. It is shown that two cure-dependent model parameters, i.e., the smallest size of the cooperatively rearranging region and the glass transition temperature, are sufficient in accounting for the effect of cure on the relaxation modulus, and could provide a physical explanation of the influence of cure on relaxation behaviors. Furthermore, the proposed model is numerically realized by incorporating ABAQUS with UMAT subroutine, and its validity in predicting the residual stresses and final distortion of composites is also numerically verified by comparing with the results available in literature.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal and thermo-mechanical post-buckling analysis of GNP-reinforced composite laminated plates GNP 增强复合层压板的热和热机械屈曲后分析

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-04 DOI: 10.1016/j.mechmat.2024.105171

{"title":"Thermal and thermo-mechanical post-buckling analysis of GNP-reinforced composite laminated plates","authors":"","doi":"10.1016/j.mechmat.2024.105171","DOIUrl":"10.1016/j.mechmat.2024.105171","url":null,"abstract":"<div><div>This research utilizes isogeometric analysis (IGA) method to analyze buckling and post-buckling responses of composite laminated plates embedded with graphene nanoplatelets (GNPs) subjected to three-dimensional (3D) conduction of heat or combined 3D heat conduction and mechanical edge compression. A formulation to determine temperature profile produced by 3D conduction of heat in the GNP-reinforced laminate is established, and a new function with smooth transition form of GNP volume fraction across the thickness is presented for dictating the volume fraction of layer. Shear deformable quasi-3D theory with the von Kármán type nonlinearity which takes initial geometric deformation and thermal effect into consideration is employed to construct the nonlinear equilibrium states. Four types of GNP arrangements encompassing uniform, O, X and V shapes are considered. The IGA approach presented, through the benchmark test, is evidenced to estimate the thermal buckling temperature accurately and to successfully trace the thermal post-buckling path. Additional parametric study is carried out to scrutinize the thermal and the thermo-mechanical post-buckling features of the GNP-reinforced composite laminated plates, and the new findings are sure to be served as the benchmark solutions.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The role of secondary voids in the mechanism of ductile fracture at a crack tip 二次空隙在裂纹尖端韧性断裂机制中的作用

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-10-01 DOI: 10.1016/j.mechmat.2024.105170

{"title":"The role of secondary voids in the mechanism of ductile fracture at a crack tip","authors":"","doi":"10.1016/j.mechmat.2024.105170","DOIUrl":"10.1016/j.mechmat.2024.105170","url":null,"abstract":"<div><div>The mechanics and mechanisms of ductile fracture, ahead of a blunting crack tip, have been studied extensively. Several computational studies analyzing the effect of initial void volume fraction, void shape, void spatial distribution and the mode of loading (<span><math><mrow><msub><mrow><mi>K</mi></mrow><mrow><mi>I</mi></mrow></msub><mo>,</mo><msub><mrow><mi>K</mi></mrow><mrow><mi>I</mi><mi>I</mi></mrow></msub></mrow></math></span> etc.) on crack-void interaction and its consequence on the mechanism of fracture have been reported. The influence of small size secondary voids on the failure of ligament between the large primary voids and, hence, on fracture toughness has been analyzed using the Gurson-type homogenized models of ductile fracture. In the present work, the two populations of voids ahead of a crack tip are modeled discretely. A plane strain, central line cracked boundary layer model under small-scale yielding is considered. The role of initial shape and spatial distribution of secondary voids, matrix strain hardening and mode of imposed loading in the mechanism of ductile crack growth initiation and advance is analyzed in detail. For completeness sake, numerical calculations are also performed using a homogenized representation of the secondary voids. The results so obtained are then compared with the predictions based on discrete modeling of the secondary voids. Our numerical studies revealed that plastic flow localization resulting from a small initial volume fraction of favorably distributed secondary voids may alter the path of crack growth initiation and advance, thus, influencing the ductile fracture toughness.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Failure analysis of unidirectional fiber reinforced plastics based on computational micromechanics and PUCK failure theory 基于计算微机械学和 PUCK 失效理论的单向纤维增强塑料失效分析

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-09-27 DOI: 10.1016/j.mechmat.2024.105169

{"title":"Failure analysis of unidirectional fiber reinforced plastics based on computational micromechanics and PUCK failure theory","authors":"","doi":"10.1016/j.mechmat.2024.105169","DOIUrl":"10.1016/j.mechmat.2024.105169","url":null,"abstract":"<div><div>Achievement of accurate and reliable failure criterion is fundamentally important for designing composite structures. This study comprehensively evaluated the failure of unidirectional fiber-reinforced plastics (FRP) from the perspectives of failure theory and computational micromechanics. Further, PUCK failure criterion was analyzed in detail to identify the specific effects of the interfacial reinforcement coefficient on the failure mechanism. The representative volume element model of FRP with randomly distributed fibers was established. The comparative analysis of the results between current failure theory and experiment, indicates that the load bearing capacity of FRP under bi-axial compressive stress and shear stress is understated by the PUCK failure criterion. Microscopic finite element analysis was adopted to investigate the failure envelope of FRP, considering interface reinforcement coefficient. The results reveal that the strength of FRP under the combination of moderate transverse compressive stress and in-plane shear stress is significantly affected by the interface reinforcement coefficient. The accuracy of PUCK failure criterion heavily depends on the value of the interface reinforcement coefficient and if the criterion does not consider the coefficient, it can cause notable error on strength prediction. Consequently, determination of interface reinforcement coefficient would be helpful to achieve more accurate failure criterion for FRP.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantification of elastic incompatibilities at triple junctions via physics-based surrogate models 通过基于物理学的代用模型量化三重连接处的弹性不相容性

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-09-27 DOI: 10.1016/j.mechmat.2024.105163

{"title":"Quantification of elastic incompatibilities at triple junctions via physics-based surrogate models","authors":"","doi":"10.1016/j.mechmat.2024.105163","DOIUrl":"10.1016/j.mechmat.2024.105163","url":null,"abstract":"<div><div>Stresses resulting from elastic incompatibilities at grain boundaries have long been known to drive the premature failure and loss of desirable macroscopic properties in polycrystalline materials. In this work, we employ machine learning to create a surrogate model that furnishes a functional relationship between grain boundary configurational data and metrics of incompatibility. A planar triple junction geometry composed of cubic grains rotated about their <span><math><mrow><mo>[</mo><mn>001</mn><mo>]</mo></mrow></math></span> axis was adopted as the grain boundary model. High-fidelity finite element simulations of this triple junction under hydrostatic extension were used to generate a synthetic dataset for training the surrogate model. A set of <span><math><mi>J</mi></math></span> integrals computed around microcracks placed along the triple junction boundaries were used to quantify the elastic incompatibilities between the grains. Using the grain rotation angles and <span><math><mi>J</mi></math></span> integrals as the feature and label data respectively, a multi-layer perceptron network was trained using the synthetic data produced with the physics-based model. We demonstrate that the network trained using data from the physics-based model establishes an accurate functional dependence between the triple junction angles and the <span><math><mi>J</mi></math></span> integrals that enables direct and fast evaluation. We use the surrogate model to efficiently sweep the configuration space and create contour maps of the largest stress intensification at the triple junction as a function of the grain rotation angles. Furthermore, we show that the analytical properties of the surrogate model can be utilized to identify the most and least compatible triple junction configurations via optimization.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A variational method for the simulation of hydrogen diffusion in metals 模拟金属中氢扩散的变分法

IF 3.4 3区材料科学

Mechanics of Materials Pub Date : 2024-09-25 DOI: 10.1016/j.mechmat.2024.105166

引用次数: 0