Increasing Shear Strain Research Articles

Thermomechanical Stress Analysis of Hydrated Vital Gluten with Large Amplitude Oscillatory Shear Rheology.

Vital gluten is increasingly researched as a non-food product for biodegradable materials. During processing, the protein network is confronted with increased thermal and mechanical stress, altering the network characteristics. With the prospect of using the protein for materials beyond food, it is important to understand the mechanical properties at various processing temperatures. To achieve this, the study investigates hydrated vital gluten under thermomechanical stress based on large amplitude oscillatory shear (LAOS) rheology. LAOS rheology was conducted at increasing shear strains (0.01-100%), various frequencies (5-20 rad/s) and temperatures of 25, 45, 55, 65, 70 and 85 °C. With elevating temperatures up to 55 °C, the linear viscoelastic moduli decrease, indicating material softening. Then, protein polymerization and the formation of new cross-links due to thermal denaturation cause more network connectivity, resulting in significantly higher elastic moduli. Beyond the linear viscoelastic regime, the strain-stiffening ratio rises disproportionately. This effect becomes even more evident at higher temperatures. Lacking a viscous contribution, the highly elastic but also stiff network shows less mechanical resilience. Additionally, at these elevated temperatures, structural changes during the protein's denaturation and network shrinkage due to water evaporation could be visualized with confocal laser scanning microscopy (CLSM).

Determination of Dynamic Properties of Fine-Grained Soils at High Cyclic Strains

Shear modulus (SM) and damping ratio (DR) are significant in seismic design and the performance of geotechnical systems. The evaluation of soil reactions to dynamic loads, such as earthquakes, blasts, train, and traffic vibrations, necessitates the estimation of dynamic SM and DR. The aim of this research is to determine the cyclic parameters of unsaturated soils in and around Peshawar, and how these properties depend upon the varied confining pressures and shear strains. Undisturbed samples were collected using Shelby tubes from five boreholes at different locations along Jamrud Road, Peshawar. The index properties (grain size distribution, plasticity index, and specific gravity) and dynamic properties of these samples were determined. Three samples of 100 mm in height and 50 mm in diameter were obtained from each Shelby tube. After preparing and mounting the sample in the triaxial cell, the sample is first saturated by increasing the cell and back pressures in increments of 50 kPa until the value of Skempton’s pore pressure parameter (B) reaches ≥ 0.96. Samples were consolidated at confining pressures of 150, 200, and 300 kPa, then subjected to cyclic shear strains of 0.2, 1, 2, 2.5, and 5%. Shear stress–strain hysteresis loops were plotted, and the values of SM and DR were calculated for each cycle. Generally, at shear strains of 0.2 and 1%, the slope of the loops is steep, and gradually becomes gentler at higher strains of 2, 2.5, and 5%. It is found that, with an increasing number of cycles, the SM and DR decrease. The SM decreases with increasing shear strain, whereas the DR increases at shear strains of 0.2–1%, then decreases for strains of 2, 2.5, and 5%. The confining pressure has more influence at a shear strain of 0.2–1%, while little effect has been observed at a shear strain of 2.2–5%. The values of SM are higher at higher confining pressures at a given shear strain. The results show higher stress values during the initial cycles because of the greater effective stress that developed in response to shear strain while, with an increase in the number of cycles, the pore water pressure gradually increases, thereby reducing the effective stress and weakening the bonds between soil particles. In dynamics, when the confining pressure increases, particles are closer to contact, so the travel paths of waves increase. The energy loss will increase, so DR will decrease.

Particle shape effects on dynamic properties of granular soils: A DEM study

Particle shape is an essential aspect of granular soils that affects their mechanical properties. It is challenging to isolate the effect of particle shape from other mechanical properties such as inter-particle friction coefficient and particle shear modulus in laboratory tests. The discrete element method (DEM) makes it feasible to investigate the effect of macroscopic and mesoscopic particle morphologies including sphericity and roundness. This study provides a systematical DEM investigation of the particle shape effect on the dynamic properties of granular soils by simulating cyclic undrained triaxial tests at various initial confining pressures and void ratios. The results indicate that specimen consisting of angular particles generally exhibit a higher secant shear modulus G than that of rounded particles. Additionally, particle shape has no significant effect on modulus ratio G/G0 but a noticeable impact on damping ratio D at relatively large strains due to dilatancy. A weighted coordination number CN' was proposed to reveal the microscopic effect of particle shape on G0. Contact sliding was found to be the main cause of modulus degradation and damping increase with increasing shear strain. The tangential shear modulus ratio Gtan/G0 is inversely correlated to the weighted contact sliding ratio fs'.

Response of cohesive–frictional soils at small to medium shear strain levels from thermo-controlled resonant column testing

The shear modulus and damping ratio are arguably the two most crucial soil parameters to be used in seismic site-response analyses and a wide variety of other geotechnical engineering applications involving soil materials subjected to dynamic loading. The dependency of these parameters on the level of load-induced shear strains in the field has been investigated rather extensively for different types of soils. Most experimental studies, however, have relied on a limited set of controlled environmental factors and stress variables, mainly soil moisture and confinement. The present work is an attempt to gain further insights into the possible impact of an additional critical factor: soil temperature. A resonant column apparatus was upgraded to assess the dynamic response of three types of cohesive–frictional soils as they transitioned from linear to nonlinear behavior under thermo-controlled cyclic torsional loading. Emphasis was placed on shear modulus degradation, and hence variation in damping ratio, with increasing shear strain amplitude (cyclic torque magnitude). Results showed a mostly detrimental effect of increasing soil temperature on the normalized shear modulus, damping ratio, and threshold shear strain of clayey, silty, and sandy soils when subject to small to medium shear strain levels.

Towards enhancing the ductility of AZ31 Mg alloys by controlling twin orientation at various shear strain levels

In this work, a novel texture control strategy, shear strain-induced twin orientation regulation (SITOR), was employed to fabricate the Mg–3Al–1Zn (AZ31) alloy with significantly improved ductility. The SITOR-1P sample processed at 250 °C exhibited a homogeneous microstructure and an almost ideal shear texture (c-axes of grains tilted 45° from the extrusion direction to the transverse direction), which resulted in an enhanced fracture elongation from 14.3% to 30.6% owing to the high activity of basal slip when compared with as-extruded Mg alloys. With increasing shear strain, the concentration of shear texture components in the SITOR-4P sample increased, leading to further improvement in its mechanical performance. While specimens produced by the conventional shear strain-induced orientation regulation (SIOR) method also underwent the same 4 passes of shear deformation, both their texture deflection and performance enhancement remained limited. The current investigation proposes a viable way to largely activate basal slip via the SITOR scheme, therefore offering a fresh perspective for addressing the poor plasticity of Mg.

Study on dynamic properties of ultrasoft clay based on large amplitude oscillatory shear tests

In offshore engineering, the dynamic properties of ultrasoft clay in the seabed could affect the stability of offshore construction under dynamic loading. The typical rheological response of ultrasoft clay is studied based on the test results from large amplitude oscillatory shear tests with a rheometer. The ultrasoft clay undergoes three phases: the solid phase, transition phase and liquid phase, under dynamic loading. Modulus overshoot is observed when a phase transition occurs. The shear modulus and damping ratio of ultrasoft clay are studied based on the relationship between rheological parameters and dynamic parameters. The results show that the maximum shear modulus of ultrasoft clay could be expressed as a function of water content. Compared with general clay, the normalized shear modulus of ultrasoft clay decreases, and the damping ratio rapidly increases with increasing shear strain. Models describing the change in the normalized shear modulus and damping ratio with the shear strain of ultrasoft clay are suggested based on our test results. This study could aid in the evaluation of the stability of submarine structures at the seabed level under dynamic loading.

Spot–Ladder Selection of Dislocation Patterns in Metal Fatigue

Spontaneous pattern formation by a large number of dislocations is commonly observed during the initial stages of metal fatigue under cyclic straining. It was experimentally found that the geometry of the dislocation pattern undergoes a crossover from a 2D spot-scattered pattern to a 1D ladder-shaped pattern as the amplitude of external shear strain increases. However, the physical mechanism that causes the crossover between different dislocation patterns remains unclear. In this study, we theorized a bifurcation diagram that explains the crossover between the two dislocation patterns. The proposed theory is based on a weakly nonlinear stability analysis that considers the mutual interaction of dislocations as a nonlinearity. It was found that the selection rule among the two dislocation patterns, “spotted” and “ladder-shaped”, can be described by inequalities with respect to nonlinearity parameters contained in the governing equations.

A Microstructure-Based Mechanistic Approach to Detect Degeneration Effects on Potential Damage Zones and Morphology of Young and Old Human Intervertebral Discs.

There is an increasing demand to develop predictive medicine through the creation of predictive models and digital twins of the different body organs. To obtain accurate predictions, real local microstructure, morphology changes and their accompanying physiological degenerative effects must be taken into account. In this article, we present a numerical model to estimate the long-term aging effect on the human intervertebral disc response by means of a microstructure-based mechanistic approach. It allows to monitor in-silico the variations in disc geometry and local mechanical fields induced by age-dependent long-term microstructure changes. Both lamellar and interlamellar zones of the disc annulus fibrosus are constitutively represented by considering the main underlying microstructure features in terms of proteoglycans network viscoelasticity, collagen network elasticity (along with content and orientation) and chemical-induced fluid transfer. With age,anoticeable increase in shear strain is especially observed in the posterior and lateral posterior regions of the annulus which is in correlation with the high vulnerability of elderly people to back problems and posterior disc hernia. Important insights about the relation between age-dependent microstructure features, disc mechanics and disc damage are revealed using the present approach. These numerical observations are hardly obtainable using current experimental technologies whichmakes our numerical tool useful for patient-specific long-term predictions.

Laboratory investigation on liquefaction of sands and cemented sand mixes

ABSTRACT Liquefaction is considered one of the most common phenomena resulting in serious damage during earthquakes. Appropriate estimation of liquefaction potential, damping characteristics and shear modulus of soil under dynamic loading is crucial for precise dynamic response analysis and soil modelling problems. The present paper emphasises the influence of relative density, confining pressure, and shear strain on the cyclic response of sand specimens. A parametric study comprising varying relative densities (35–65%), confining pressures (100–150 kPa), and shear strain (0.015–1.3%) under 1 Hz loading frequency was conducted in the laboratory. The sand samples were subjected to a series of consolidated undrained cyclic triaxial tests. It is observed that with an increase in confining pressure and relative density, the pore pressure ratio reduced; whereas an increase in pore pressure ratio was witnessed with an increase in shear strain. The influence of cement inclusion on the cyclic response of the specimens is evaluated for varying cement contents (1–4%). The addition of 4% cement considerably enhanced the strength of sand and arrested the liquefaction instigation.

Study on the Dynamic Characteristics of Loess

Due to its special material composition, formation environment, and special structure, loess usually shows different engineering and dynamic characteristics from ordinary soil. Based on previous research results, this paper studies the Haiyuan loess. It is found that: (1) the variation coefficients of various physical properties (except for the liquid index) of loess in the region are relatively stable, but the mechanical properties are relatively discrete; (2) the correlation among natural water content, void ratio, and density is high, but the correlation between mechanical properties is poor; (3) the consolidation ratio, effective confining pressure, and dynamic shear modulus ratio change in direct proportion, while the damping ratio changes in the opposite direction with increasing shear strain; and (4) in this paper, the recommended model of shear wave velocity and burial depth of loess in the study area is given. Compared with the example, the error is smaller and more reliable. (5) The characteristic period of the seismic response spectrum of the loess soil layer is not sensitive to the change in the damping ratio, and the change amplitude is small.

Characteristics of dynamic shear modulus and damping ratio and the structural formula of EPS particles lightweight soil

Dynamic triaxial tests of lightweight soil were conducted to explore the dynamic characteristics of expanded polystyrene (EPS) particle lightweight soil under traffic load. The effects of different mixed ratios, confining pressure, frequency on the backbone curves, dynamic shear modulus, and damping ratio characteristics of lightweight soil were investigated. The maximum dynamic shear modulus formula and maximum damping ratio formula of lightweight soil were established. The results indicated that backbone curves of lightweight soil had typical nonlinear and strain-hardening characteristics. With an increase in dynamic shear strain, the dynamic shear modulus curves appeared as inverse “S-shaped”. The dynamic shear modulus in the initial stage varied under different confining pressures. For γd＞10−4, the attenuation rate of the dynamic shear modulus increased with an increase in the dynamic shear strain, and for γd＞10−2, the relationship curve between the dynamic shear modulus and dynamic shear strain coincided gradually, and the attenuation process then stabilized. Owing to the special structure of lightweight soil, the damping ratio curves were “Bell-shaped” and “S-shaped.” Both the confining pressure and compressive yield stress determined the change trends of the damping ratio curves of the lightweight soil. The specimens were in an over-consolidated state and the mixed soil was in the state of shear dilatancy under dynamic loads when the confining pressure was less than the compressive yield stress, resulting in “Bell-shaped” damping ratio curve. The specimens were in the normal consolidated state and the mixed soil was in the state of shear shrinkage under dynamic loads when the confining pressure was greater than the compressive yield stress, resulting in “S-shaped” damping ratio curves. The calculation methods of the relative structural degree k and generalized void ratio e' of lightweight soil were defined to express the structural damage laws of lightweight soil having different mixed ratios under complex stress conditions using a unified formula. Based on Hardin's empirical formulas, the maximum dynamic shear modulus and maximum damping ratio formulas of lightweight soil were established by introducing the relative structural degree k and generalized void ratio e'. The formulas can quantitatively describe the dynamic responses of the special structure of lightweight soil under complex stress conditions.

Mechanical Properties and Microstructural Evolutions of High-Pressure Torsion-Processed Al7068 Alloy

The combination of severe plastic deformation, deformational heat, and frictional heat generated during the high-pressure torsion process has a great effect on microstructural evolutions, including grain refinement, dynamic recrystallization and recovery. In particular, the low melting temperature metallic alloys (e.g., aluminum and magnesium) also induce nano-precipitations in the matrix during high-pressure torsion, which results in both unique microstructure and mechanical properties of the nanocrystalline metallic materials. In this study, the mechanical properties and microstructural evolution of high-pressure torsion-processed aluminum 7068 alloy at room temperature were investigated. In the early deformation stage, both grain refinement and nano-precipitates were formed that increase the strength of ultrafine-grained aluminum alloy, and a maximum strength of 844 MPa was obtained for the 5T sample. However, in the later deformation stage, tensile strength decreases with the increase in shear strain due to grain growth, and coarse precipitates act as crack initiation sites during plastic deformation. In summary, the mechanical properties of high-pressure torsion represent the strength-ductility trade-off as the increase of the number of revolutions. Their mechanical properties are superior to those of recent severe plastic deformation-processed aluminum alloys. This result shows that the severe plastic deformation of the HPT process positively contributes to their mechanical properties by inducing multiple strengthening paths, such as grain refinement and nano-precipitation of the aluminum alloy.

INVESTIGATION OF RHEOLOGICAL PROPERTIES OF A NANOCOMPOSITE OF SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES WITH POLYETHYLENE GLYCOL

This paper presents the results of a new investigation of the rheological properties of a nanocomposite of superparamagnetic iron oxide nanoparticles (SPIONs) with polyethylene glycol (PEG). The surface of the nanocomposite had no electrical charge and the SPIONs were coated with the polymer. The investigations were performed at different temperatures and the results were compared on different rheological parameters. The steady-state behavior of samples was observed at 20 °C and 40 °C and a small increase of viscosity versus shear strain, shear rate or time was revealed at 60 °C. Moreover, the shear stress increase was observed with the increase of shear rate and shear strain. The slopes of the corresponding changes were higher at 20 °C and decreased with the increase in temperature. The torque values increased with shear strain and time. The same phenomenon concerning the different slopes at different temperatures was observed for the torque-shear strain and torque-time variations. These results showed that the rheological properties of the nanocomposite depended on the temperature and could change with the temperature increase. An advantage of this study was that the comparative investigation of the rheological properties of nanocomposite at different temperatures was carried out. The other advantage was that the effect of the coating of the SPIONs with the polymer was observed in the obtained results. This new investigation of the nanaocomposite of SPIONs-PEG coated with PEG can provide comparative data for more investigations of the surface charged SPIONs coated with this polymer. These studies can provide information for a further investigation of the effect of the surface charge of SPIONs in the polymeric matrix on their rheological properties.

An evaluation of the effect of matric suction on the dynamic strain-dependent parameters of an unsaturated silt

This research investigates the influence of matric suction on the variation of shear modulus and damping ratio of a silty soil in very small to medium shear strain levels. A set of laboratory experiments including three bender elements tests in addition to three resonant column-torsional shear tests have been carried out on unsaturated Firuzkuh silt specimens. In this regard, an unsaturated triaxial cell equipped with a set of bender elements and a resonant column-torsional shear device that can apply and control matric suction have been used. All specimens had an initial void ratio of 0.7 and were tested in various matric suctions under a net mean stress of 50 kPa. For this purpose, the axis translation technique has been implemented for applying matric suction, and High Air Entry Value (HAEV) ceramic discs have been used for air-water control of unsaturated silt specimens. According to the results, a significant variation of shear modulus and damping ratio has been observed with changes in matric suction and shear strain level. The output data indicate that shear modulus increases with increasing matric suction while the damping ratio decreases with an increase in matric suction. In addition, shear modulus and damping ratio decrease and increase with increasing shear strain, respectively.

A small-strain soil constitutive model for initial stiffness evaluation of laterally loaded piles in drained marine sand

Three-Dimensional Finite-Element Method (3-D FEM) analyses were performed to investigate the initial stiffness of the laterally loaded piles in drained marine sand. A small-strain soil constitutive model developed based on Menq model was implemented in the 3-D FEM model to simulate the response of laterally-loaded piles in the sand over a range of small displacements. The model incorporated how the shear modulus for sand increased with the mean effective stress and decreased non-linearly with the increasing shear strain. The procedure of calibrating the model was proposed based on fitting the measurements from both laboratory tests and in-situ site investigation This soil constitutive model was implemented within a 3-D FEM analysis using an isotropic material with strain-induced anisotropy behavior in order to simulate the response of laterally-loaded piles under monotonic loading. A comparison of model predictions with laboratory and field test results indicated that this model had the promise to simulate the non-linear relationship between lateral load and pile-head deflection for mudline deflections ranging from less than 0.25-percent of the pile diameter.

Strength Characteristics of Biochar-Amended Clay Covered Soil Mixed with Methane-Oxidizing Bacteria

Adding biochar to soil can improve the soil’s physical–chemical properties, microscopic pore structure, and bacterial habitat. This affects the soil’s strength characteristics and the oxidization of methane. Using a Humboldt pneumatic direct shear instrument, this study investigated the effect of the amount of biochar in the soil, the soil’s methane-oxidizing bacteria, aeration time, and carbon content on the strength characteristics of a biochar-amended clay. The results show that when the biochar content is low, the soil’s stress–strain curve shows a strain hardening state as the strain increases. When the biochar content is greater than 10%, the methane-oxidizing bacteria increase as the shear strain increases. The stress–strain curves of the biochar–clay mixture all showed a softened state. Under the same biochar content, the soil’s stress–strain curves show strain softening as the methane filling time increases. However, with an increase in the amount of biochar, cohesion gradually increased and the internal friction angle did not change significantly. A scanning electron microscope (SEM) image of the biochar–clay mixture with methane oxidizing bacteria revealed the influence of the evolution law of the samples’ micropore structure on the soil’s stress–strain curve and strength properties.

Characterization of dislocation microstructures in near-[formula omitted] single crystal copper using high-voltage scanning transmission electron microscopy

Metallic structures are prone to failure caused primarily by fatigue-related damage to the structural material. Fatigue behavior is strongly correlated with dislocation structures in metals. Therefore, investigating the formation of dislocation structures is essential for understanding the fatigue process. The dislocation structure in face-centered cubic crystals has a strong orientation dependence. However, the detailed characteristics and evolution process of dislocation structures of fatigued [1‾11] single crystal copper are still insufficient. This study investigated dislocation structures in near-[1‾11] single crystal copper cyclically deformed at room temperature under different constant plastic shear strain amplitude (γpl) to analyze the formation mechanism of dislocation structures and their relationship with fatigue behavior. Characteristic dislocation structures were characterized by adopting multiple planes using a high-voltage scanning transmission electron microscope. With increasing shear strain amplitude, a vein-like structure along the (1‾11) plane gradually developed into a wall structure. When γpl ≥ 1 × 10−3, deformation bands and cell bands were formed to accommodate the higher plastic strain. The state of cell-band development significantly affected the cyclic softening of the single crystal copper. A positive linear relationship existed between the shear stress amplitude and the reciprocal of the cell width.

Flowslide High Fluidity Induced by Shear Thinning

AbstractRainfall‐induced flowslides and the subsequent debris flows are the most recurrent and destructive natural hazards due to their high velocity and long‐distance runout. It is widely accepted that shear‐induced excess pore pressure controls the high fluidity in flowslide movement. Nevertheless, flume experiments demonstrate that flowslides can exhibit high fluidity even in the absence of excess pore pressure, demonstrating that even saturated granular matter has an intrinsic shear‐velocity‐dependent fluidization mechanism. Herein, drained ring shear experiments were conducted to obtain a further understanding of the fluidity of the saturated granular material. By means of a transparent shear chamber, the shear‐zone thickness and the velocity gradient within samples could be directly observed and thus its rheology could be well determined. The granular soil showed substantial shear‐thinning even in the absence of excess pore pressure, which could well explain the high fluidity in flowslide dynamics in addition to excess pore pressure, especially during rapid shear. Acoustic emissions (AEs) in the ring shear device provided additional evidence of the rheological mechanism. The macroscopic apparent viscosity of the granular system was weakened by rapid shear accompanied by increasing AE power. We propose that increasing grain pressure associated with increasing shear strain rate weakens intergranular frictional contacts between granular layers, thus weakening the apparent viscosity, and vice versa. By using AE measurements combined with dimensionless number analysis, we suggested that shear‐thinning is one of the most pivotal mechanisms accounting for the ultra‐high fluidity in flowslides.

Cyclic simple shear behavior of a tropical alluvial soil

Tropical alluvial soil has distinctive physical characteristics when compared to common sedimentary soils. Ignoring such distinctive characteristics might lead to geotechnical problems that require a thorough re-investigation. Foundation failures have been identified along some river banks of tropical alluvial soil deposits in Sarawak, Malaysia, which were speculated to be due to cyclic loading effects. This paper presents preliminary results on tropical alluvial soil engineering behaviors from simple shear cyclic loading tests. Specimens measuring 50 mm in diameter and 16 mm in height were obtained from three undisturbed samples. They were sheared using an Electro-Mechanical Dynamic Cyclic Simple Shear (EMDCSS) for thirty cycles at three different target displacements. The results showed hysteresis loops, where the shear stress decreases as the cycle increases. Excess pore water pressures develop during shearing, which correspond to the target displacement levels. The damping ratio increases as the shear strain increases but decreases as the cycle increases. The normalized shear modulus decreases as both the shear strain and loading cycle increase. A comparison with previous literature on cohesive soils shows that the tropical alluvial soil has a lower damping ratio and normalized shear modulus, which range from 3.3% to 9% and 0.0004 to 0.01, respectively. The findings indicate that the tropical alluvial soil has a potential reduction in strength when subjected to continuous cyclic loading. The paper provides a better understanding for academics and engineering professionals before conducting design or remedial work in the tropical alluvial soil environment.

Fabrication and modelling of Si3N4 ceramics with radial grain alignment generated through centripetal sinter-forging

• Textured silicon nitride (Si 3 N 4 ) ceramic, with radial grain alignment, was prepared by a novel centripetal sinter-forging using spark plasma heating at 1800 °C in 10 min. • The average values of the included angles between the c -axis of the local Si 3 N 4 grain and radial direction were as low as 16.4° and 11.0° on the section plane perpendicular to the pressing direction and parallel to both the pressing and radial directions, respectively. • A fundamental physical model was created to simulate the texture formation during the 3-dimentional strain reorientation, which revealed the rod-like grain would preferentially rotate toward the center of the sample under the flow motion in centripetal direction during sintering. Silicon nitride (Si 3 N 4 ) based ceramics are one of the most attractive advanced engineering materials, which have been widely used under high-speed rotational operation or for mechanical contacts across a curved surface. In the present study, rotationally symmetric texturing of Si 3 N 4 , with radial grain alignment, was obtained by centripetal sinter-forging (CSF) of a partially sintered sample. The average values of the included angles between the c -axis of the local Si 3 N 4 grain and radial direction were approximately 16.4° and 11.0°, on the section plane perpendicular to the pressing direction, and parallel to both the pressing and radial directions, respectively. The compressive strain in the pressing direction forced the ceramic body to flow towards the central axis, resulting in compressive strain in the tangential direction and tensile strain in the radial direction. A fundamental physical model was created to simulate the grain rotation during the 3-dimentional strain reorientation, which revealed the rod-like grain would preferentially rotate toward the center of the sample under the CSF process. In addition, due to the friction between the sample surface and the pressing punch, the increased shear strain could enhance the Si 3 N 4 grain alignment. Consequently, ceramics with rod-like grains perpendicular to the curved side surface could be anticipated by applying the centripetal forming concept in a controlled manner.