scholarly journals Uniaxial tensile deformation and fracture process of structures forming by unsaturated intercalation of amine molecule into C–S–H gel

2022 ◽  
Vol 28 (1) ◽  
Author(s):  
Dawei Sun ◽  
Yan Zheng ◽  
Jianhua Yan ◽  
Yali Wang ◽  
Jianfeng Wang ◽  
...  
Keyword(s):  
Fracture Process ◽  
Tensile Deformation ◽  
Uniaxial Tensile ◽  
Deformation And Fracture ◽  
Amine Molecule

scholarly journals Uniaxial Tensile Deformation And Fracture Process of Structures Forming By Unsaturated Intercalation of Amine Molecule Into C–S–H Gel

2021 ◽  
Author(s):  
Dawei sun ◽  
Yan Zheng ◽  
Jianhua Yan ◽  
Yali Wang ◽  
Jianfeng Wang ◽  
...  
Keyword(s):  
Fracture Process ◽  
Tensile Deformation ◽  
Mean Square Displacement ◽  
Local Stress ◽  
Dynamics Simulation ◽  
Elastic Behavior ◽  
Uniaxial Tensile ◽  
Deformation And Fracture ◽  
Amine Molecule ◽  
Interlayer Region

Abstract The application of cement based materials in engineering requires the understanding of their characteristics and subsequent deformation and fracture process of C-S-H gel in service. In this work, three types of amine molecules including TEPA, PAM and TEA were intercalated unsaturatedly into C–S–H gel successfully. Systematical analysis was performed on the structures and properties on both C–S–H gel and corresponding amine molecules / C–S–H gel. It was found that unsaturated intercalation of amine molecules into C–S–H gel plays a key role in the geometry and therein density of nanocomposites. Subsequently, radial distribution function (RDF), time correlated function (TCF) and mean square displacement (MSD) were applied to characterize the structure and dynamic information of the as-generated nanocomposites, demonstrating the occurance of interaction between amine molecules with Ca–Si layer and acceleration of water diffusion by unsaturated intercalation of amine molecules into the interlayer region in C–S–H gel. Finally, deformation and fracture process of C–S–H gel and amine molecules / C–S–H gel under uniaxial tensile loads were displayed by molecular dynamics simulation. It was indicated that Young’s modulus of nanocomposites demonstrates a strain softening nature, indicating a visco-elastic behavior. The breakage of Ca–O bonds and hydrogen bonds dominates the fracture of C–S–H gel. Weak interaction for TEPA / C–S–H gel or TEA / C–S–H gel leads to a decreased tensile strength. Local stress concentration in other interlayer region governs the deformation and fracture process in spite of the formation of strong interaction between double bonded polar oxygen atoms in PAM molecules and Ca atoms in C–S–H gel.

Atomistic Study on Nano Stress-Strain Curves of α-Fe

1997 ◽  
Vol 492 ◽  
Author(s):  
Shenyang Hu ◽  
Matthias Ludwig ◽  
Liam Farrissey ◽  
Siegfried Schmauder
Keyword(s):  
Boundary Conditions ◽  
Tensile Deformation ◽  
Tensile Axis ◽  
Plane Boundary ◽  
Uniaxial Tensile ◽  
Stress Strain ◽  
Fracture Characteristics ◽  
Deformation And Fracture ◽  
Dislocation Movement ◽  
Atomistic Study

ABSTRACTThe atomistic processes and stress-strain-curves during uniaxial tensile deformation of a single α-Fe nanocrystal have been studied with the molecular static method. Periodic boundary conditions are imposed along one direction perpendicular to the tensile axis to model plane strain conditions. The effects of the model sizes in plane, boundary conditions and crystal orientations on the stress-strain curves are systematically analyzed. Various deformation evidences such as dislocation movement, dislocation piling up and twinning are clearly observed. The deformation and fracture characteristics of a-Fe and their dependencies on the boundary conditions are investigated.

scholarly journals The Influence of Different Microstructure on Tensile Deformation and Acoustic Emission Behaviors of Low-Alloy Steel

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4981
Author(s):  
Wenbin Ma ◽  
Hongyun Luo ◽  
Zhiyuan Han ◽  
Linyan Zhang ◽  
Xiaoguang Yang
Keyword(s):  
Acoustic Emission ◽  
Fracture Process ◽  
Tensile Deformation ◽  
Lath Martensite ◽  
High Amplitude ◽  
High Yield ◽  
Low Alloy Steels ◽  
Continuous Type ◽  
Deformation And Fracture ◽  
Alloy Steels

The effect of different microstructures, obtained under different tempering temperatures on acoustic emission (AE) characteristics and source mechanisms during tensile deformation, was investigated in this study. Different heat treatments were carried out on hot-rolled low-alloy steels to obtain different microstructures (ferrite/pearlite, tempered martensite and tempered sorbite) and the AE was used to monitor the deformation and fracture process of samples of different types (BM, 200 °C tempered and 600 °C tempered). The results showed that the microstructure had different influences on the high amplitude burst-type signals and low amplitude continuous-type signals during the deformation and fracture process of low-alloy steels. In the 200 °C tempered sample, the continuous-type signals were enhanced by the high yield stress and dislocation velocity induced by the block of the lath martensite whose substructure was high-density dislocation. On the other hand, the interaction of the precipitates with the local dislocations increased the intensity of AE events, thus generating burst-type signals with higher amplitude in the 600 °C tempered samples.

Peculiarities of tensile deformation and fracture of high-nitrogen steel obtained by electron beam additive manufacturing

2020 ◽  
Author(s):  
Sergey V. Astafurov ◽  
Elena G. Astafurova ◽  
Kseniya A. Reunova ◽  
Evgenii V. Melnikov ◽  
Marina Yu. Panchenko ◽  
...  
Keyword(s):  
Electron Beam ◽  
Additive Manufacturing ◽  
Tensile Deformation ◽  
High Nitrogen Steel ◽  
High Nitrogen ◽  
Deformation And Fracture ◽  
Nitrogen Steel

scholarly journals A Flow Stress Model of 300M Steel for Isothermal Tension

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 252
Author(s):  
Rongchuang Chen ◽  
Shiyang Zhang ◽  
Xianlong Liu ◽  
Fei Feng
Keyword(s):  
Flow Stress ◽  
Constitutive Model ◽  
Tensile Deformation ◽  
Flow Behavior ◽  
Tensile Tests ◽  
Uniaxial Tensile ◽  
Model Parameters ◽  
Average Deviation ◽  
Cross Sectional ◽  
300M Steel

To investigate the effect of hot working parameters on the flow behavior of 300M steel under tension, hot uniaxial tensile tests were implemented under different temperatures (950 °C, 1000 °C, 1050 °C, 1100 °C, 1150 °C) and strain rates (0.01 s−1, 0.1 s−1, 1 s−1, 10 s−1). Compared with uniaxial compression, the tensile flow stress was 29.1% higher because dynamic recrystallization softening was less sufficient in the tensile stress state. The ultimate elongation of 300M steel increased with the decrease of temperature and the increase of strain rate. To eliminate the influence of sample necking on stress-strain relationship, both the stress and the strain were calibrated using the cross-sectional area of the neck zone. A constitutive model for tensile deformation was established based on the modified Arrhenius model, in which the model parameters (n, α, Q, ln(A)) were described as a function of strain. The average deviation was 6.81 MPa (6.23%), showing good accuracy of the constitutive model.

Formation and coalescence of strain localized regions in ferrite phase of DP600 steels under uniaxial tensile deformation

2015 ◽  
Vol 623 ◽  
pp. 133-144 ◽  
Author(s):  
A. Alaie ◽  
J. Kadkhodapour ◽  
S. Ziaei Rad ◽  
M. Asadi Asadabad ◽  
S. Schmauder
Keyword(s):  
Tensile Deformation ◽  
Ferrite Phase ◽  
Uniaxial Tensile
Sign in / Sign up

Export Citation Format

Share Document