Flat fracture propagation in mild steel: some comments on the role of plastic deformation processes

1973 ◽  
pp. 63-74 ◽  
Author(s):  
E. Smith
Keyword(s):  
Plastic Deformation ◽  
Mild Steel ◽  
Fracture Propagation ◽  
Deformation Processes

ATOMISTIC MODELING OF THE EFFECT OF TWINS ON PLASTIC DEFORMATION IN NANOCRYSTALLINE COBALT

2005 ◽  
Vol 04 (04) ◽  
pp. 651-658
Author(s):  
G. P. ZHENG
Keyword(s):  
Molecular Dynamics ◽  
Plastic Deformation ◽  
Molecular Dynamics Simulation ◽  
Tensile Deformation ◽  
Dynamics Simulation ◽  
Atomistic Modeling ◽  
Allotropic Transformation ◽  
Hexagonal Close Packed ◽  
Deformation Processes

It has been observed by experiments and computer simulations that deformation twinning and grown-in twins play important roles during the plastic deformation in nanocrystalline (nc) metals. In this study, molecular dynamics simulation is employed to investigate the role of grown-in twins in the tensile deformation of hexagonal close-packed nc cobalt. Plastic deformation processes in three types of nc samples, namely nc-cobalt without twins, with (0002) twin faults and with (1121) twins, are compared. The results show that the pre-existing twins significantly lower the mechanical strength and do not enhance the ductility of nc cobalt. Instead deformation induced hcp-to-fcc allotropic transformation is found to result in remarkable strain hardening in the modeled nc cobalt.

scholarly journals Numerical Study of Elasto-Plastic Hydraulic Fracture Propagation in Deep Reservoirs Using a Hybrid EDFM–XFEM Method

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2610
Author(s):  
Wenzheng Liu ◽  
Qingdong Zeng ◽  
Jun Yao ◽  
Ziyou Liu ◽  
Tianliang Li ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Iterative Method ◽  
Hydraulic Fracture ◽  
Iterative Procedure ◽  
Fracture Propagation ◽  
Hydraulic Fractures ◽  
Zone Model ◽  
Dilatancy Angle ◽  
Proposed Model ◽  
Hydraulic Fracture Propagation

Rock yielding may well take place during hydraulic fracturing in deep reservoirs. The prevailing models based on the linear elastic fracture mechanics (LEFM) are incapable of describing the evolution process of hydraulic fractures accurately. In this paper, a hydro-elasto-plastic model is proposed to investigate the hydraulic fracture propagation in deep reservoirs. The Drucker–Prager plasticity model, Darcy’s law, cubic law and cohesive zone model are employed to describe the plastic deformation, matrix flow, fracture flow and evolution of hydraulic fractures, respectively. Combining the embedded discrete fracture model (EDFM), extended finite element method (XFEM) and finite volume method, a hybrid numerical scheme is presented to carry out simulations. A dual-layer iterative procedure is developed based on the fixed-stress split method, Picard iterative method and Newton–Raphson iterative method. The iterative procedure is used to deal with the coupling between nonlinear deformation with fracture extension and fluid flow. The proposed model is verified against analytical solutions and other numerical simulation results. A series of numerical cases are performed to investigate the influences of rock plasticity, internal friction angle, dilatancy angle and permeability on hydraulic fracture propagation. Finally, the proposed model is extended to simulate multiple hydraulic fracture propagation. The result shows that plastic deformation can enhance the stress-shadowing effect.

scholarly journals Mechanisms of passivation and chloride-induced corrosion of mild steel in sulfide-containing alkaline solutions

2021 ◽  
Author(s):  
Shishir Mundra ◽  
John L. Provis
Keyword(s):  
Mild Steel ◽  
Surface Film ◽  
Critical Role ◽  
Chloride Concentration ◽  
Alkaline Solutions ◽  
Sulfide Concentration ◽  
Chloride Induced Corrosion ◽  
Alkaline Sulfide ◽  
High Sulfide

AbstractThe pore fluid within many concretes is highly alkaline and rich in reduced sulfur species, but the influence of such alkaline-sulfide solutions on the surface film formed on steel reinforcement is poorly understood. This study investigates the critical role of HS− in defining mild steel passivation chemistry. The surface film formed on the steel in alkaline-sulfide solutions contains Fe(OH)2 and Fe–S complexes, and the critical chloride concentration to induce corrosion increases at high sulfide concentration. However, this behavior is dependent on the duration of exposure of the steel to the electrolyte, and the nature of the sulfidic surface layer.

Plastic Deformation and Pitting Corrosion of Mild Steel in Neutral Media

1978 ◽  
Vol 13 (3) ◽  
pp. 112-117 ◽  
Author(s):  
J. Jelinek ◽  
P. Neufeld ◽  
G. A. Pickup
Keyword(s):  
Plastic Deformation ◽  
Mild Steel ◽  
Pitting Corrosion ◽  
Neutral Media

The Role of Oxidation in Laser Cutting Stainless and Mild Steel

1991 ◽  
Vol 3 (3) ◽  
pp. 41-45 ◽  
Author(s):  
A. Ivarson ◽  
J. Powell ◽  
C. Magnusson
Keyword(s):  
Mild Steel ◽  
Laser Cutting

Experimental Analysis and Crystallographic Model of Plastic Deformation after a Change of Loading Path in Mild Steel Polycrystals

1999 ◽  
Vol 578 ◽  
Author(s):  
T. Hoc ◽  
C. Rey
Keyword(s):  
Plastic Deformation ◽  
Mild Steel ◽  
Strain Localization ◽  
Loading Path ◽  
Slip Systems ◽  
Finite Element Code ◽  
Dislocation Densities ◽  
Dislocation Interactions ◽  
Sequential Tests ◽  
Microstructural Anisotropy

AbstractStrain localization in mild steel submitted to a sequential loading paths is investigated at macroscopic, mesoscopic and microscopic scales. The experimental results demonstrate that the morphology of the localization and the nominal load-displacement curves depend on the microstructural anisotropy. A crystalline model using a finite element code is proposed. The anisotropy is described by a hardening matrix whose terms correspond to dislocation-dislocation interactions and depend on the evolution of the dislocation densities on the activated slip systems during the sequential tests. The strain localization predicted by this model fits with the experimental observation and allows us to assume that localization is correlated to the saturation on the activated slip systems.

Sign in / Sign up

Export Citation Format

Share Document