Matrix Zone Research Articles

Prediction of the Ultimate Strength of Notched and Unnotched IM7/977-3 Laminated Composites Using a Micromechanics Approach.

This paper proposes a multi-scale analysis technique based on the micromechanics of failure (MMF) to predict and investigate the damage progression and ultimate strength at failure of laminated composites. A lamina’s representative volume element (RVE) is developed to predict and calculate constituent stresses. Damages that occurred in the constituents are calculated using separate failure criteria for both fiber and matrix. Subsequently, the volume-based damage homogenization technique is utilized to prevent the localization of damage throughout the total matrix zone. The proposed multiscale analysis procedure is then used to investigate the notched and unnotched behavior of three multi-directional composite layups, [30, 60, 90, −60, 30]2S, [0, 45, 90, −45]2S, and [60, 0, −60]3S, subjected to static tension and compression loading. The specimen is fabricated from unidirectionally reinforced composite (IM7/977-3). The prediction of ultimate strength at failure and equivalent stiffness are then benchmarked against the experimental test data. The comparative analysis with various failure models is also carried out to validate the proposed model. MMF demonstrated the capability to correctly predict the ultimate strength at failure for a range of multidirectional composites laminates under tensile and compressive load. The numerically predicted findings revealed a good agreement with the experimental test data. Out of the three investigated composite layups, the simulated results for the quasi-isotropic [0, 45, 90, −45]2S layup agreed extremely well with the experimental results with all the percentage errors within 10% of the measured failure loads.

Microstructure characterization and corrosion behavior of hollow ZK60 Mg profile containing longitudinal welds

The porthole die extrusion was carried out using ZK60 Mg alloy. The inhomogeneous microstructure was formed on welding and matrix zones of extruded profiles. High extrusion speed induced a temperature rise and made β1’ precipitate disappear, resulting in an obvious grain growth, change of dynamic recrystallization (DRX) mode, and higher DRX degree. The corrosion rate firstly increased due to the occurrence of localized pitting, and then decreased owing to the formation of a denser and more protective film. Low extrusion speed was harmful on the corrosion behaviors, especially in welding zone, due to the smaller grain size and more precipitates.

Mechanical Performance and Microstructure of Ultra-High-Performance Concrete Modified by Calcium Sulfoaluminate Cement

High autogenous shrinkage property is one of the disadvantages of ultra-high-performance concrete (UHPC), which may induce early age cracking and threaten the safety of concrete structure. In the present study, different dosages of calcium sulfoaluminate (CSA) cement were added in UHPC as an effective expansive binder. Hydration mechanism, autogenous shrinkage property, and compressive strength of UHPC were carried out to investigate the effect of CSA addition on the mechanical properties of UHPC. Scanning electron microscopy was also employed to characterize the intrinsic microstructural reasons relating to the changes in macroproperties. Based on the XRD diagram, increasing formation of ettringite and Ca(OH)2 can be found with increasing CSA content up to 15%. In the heat flow results of UHPC with 10% CSA addition, the maximum heat release increases to 2.6 mW/g, which is 8.3% higher than the reference UHPC, suggesting a higher degree of hydration with CSA addition. The results in autogenous shrinkage show that CSA expansion agent plays a significantly beneficial role in improving the autogenous shrinkage of UHPC. The corresponding autogenous shrinkage of UHPC is −59.66 μ ε , −131.11 μ ε , and −182.31 μ ε , respectively, at 7 d with 5%, 10%, and 15% addition, which is 108%, 117%, and 123% reduction compared to the reference specimen without CSA. In terms of compressive strength, UHPC with 5%, 10%, 15%, and 20% CSA addition has 10.5%, 17.4%, 30.2%, and 22.1% higher compressive strength than that for the reference UHPC at 28 d. Microstructural study shows that there is an extremely dense microstructure in both the bulk matrix and interfacial transition zone of UHPC with 10% CSA addition, which can be attributed to the higher autogenous shrinkage property and can therefore result in higher mechanical performance.

Investigation of dynamic pore pressure in shale gas reservoir during the multi-fracturing and its influence on fault slip

Casing deformation and micro-seismic event in shale gas reservoir has been of growing interest in the industry, which is attributed to the fault slip induced by multi-fracturing in shale gas wells. It has been widely acknowledged that the variation of pore pressure affects fundamentally the fault slip. However, the currently reported analytical models of pore pressure is not available to specially couple the key effects of shale anisotropy and accumulation of fracturing fluid induced by multi-fracturing. In this work, the characterization approach of fluid conductivity in shale reservoirs near-wellbore during multi-fracturing is established by employing the series-parallel principle. In addition, depending on Hsieh's methods, the comprehensive analytical model of pore pressure variation during multi-fracturing is established by utilizing both the matter conservation law and mechanical mechanism of fluid-solid interaction, fully incorporating the various transmissibility of the matrix, natural fracture, hydraulic fracture and fault zone in shale reservoir. Moreover, the reliability of proposed model is successfully verified through the excellent agreements compared with the numerical approach and field observation. Furthermore, the effects of perforation cluster distance, fracturing stage length, fracturing fluid viscosity and fracturing rate on faults slip are explicitly investigated, by combining the Amontons Law. The consequences demonstrate that the pore pressure variation in shale reservoir induced by hydraulic fracturing is preferentially distributed along the wellbore, fracturing area and fault zone, rather than be uniformly as the sandstone reservoir. Besides, the pore pressure at the repeated fracturing stages remains obviously high, due to the effect of the retention of fracturing fluid. The hydraulic fractures directly communicating with faults, or non-communicating but formation pressure obviously varying, are both able to trigger the fault activation. The pore pressure on fault plane still redistributes from higher pore pressure area to lower pore pressure area after fracturing, rather than stops transmitting at once. It implying that more area of the fault is active and more micro-seismic events occurs after the fracturing pump stopping. “Fewer stages with more clusters”, and the reasonable adjustment of fracturing fluid viscosity can effectively alleviate the extreme distribution of formation pressure, as well reducing the risk of fault slipping.

Diagnosing of clay distribution in argillaceous sandstone by a rock physics template

ABSTRACTThe elastic properties of argillaceous sandstones are significantly controlled, however, by the perplexing distribution of dispersed, cemented and matrix (including structural and layered) clay. The corresponding rock physics models are established to investigate the influence of different clay distribution on the elastic properties of sandstone. The rock physics modelling and laboratory experimental results exhibit that the higher the content of the matrix clay, the lower the elastic wave velocity. The dispersed and cemented clay increases the sandstone's velocity by reducing the porosity; the increase of dispersed clay only causes a slight increase in the elastic wave velocity in sandstone. In contrast, a small amount of cemented clay can significantly increase the velocity in sandstone. Based on these understandings, we construct a cross‐plot of P‐wave velocity and clay content as a template to diagnose clay distribution. Based on the rock physics model and empirical knowledge, we divide the template into four zones, namely, matrix, dispersed, cemented and mixed clay distribution zones. Then, we use the published experimental data and numerical modelling data to validate the template. Based on diagnosing the clay distribution, we introduce how to use the diagnostic results of the template to select a suitable rock physics model for argillaceous sandstone in Shengli Oil Field, East China. The selected rock physics model, guided by diagnosing the clay distribution, predicts P‐ and S‐wave velocity very well. The proposed rock physics template for diagnosing clay distribution also has potential application in well‐logging data interpretation, rock physics modelling and reservoir characterization.

Fracture Behaviour of Real Coarse Aggregate Distributed Concrete under Uniaxial Compressive Load Based on Cohesive Zone Model.

Two-dimensional meso-scale finite element models with real aggregates are developed using images obtained by digital image processing to simulate crack propagation processes in concrete under uniaxial compression loading. The finite element model is regarded as a three-phase composite material composed of aggregate, mortar matrix and interface transition zone (ITZ). Cohesive elements with traction–separation laws are used to simulate complex nonlinear fracture. During the experiment, digital image correlation (DIC) was used to obtain the deformation and cracks of the specimens at different loading stages. The concept of strain ratio is proposed to describe the effectiveness of simulation. Results show that the numerical strain ratio curve and stress–strain curves are both in good agreement with experimental data. The consistency between the cracks obtained by simulation and those obtained by DIC shows the good performance of cohesive elements as well as the effectiveness of simulation. In summary, the model is able to provide accurate predictions of the whole fracture process in concrete under uniaxial compression loading.

Utilization of BOF steel slag aggregate in metakaolin-based geopolymer

Steel slag, an industrial by-product during the steelmaking process, has not been effectively utilized so far. In this paper, the feasibility of using basic oxygen furnace (BOF) steel slag aggregate in metakaolin-based geopolymer was systematically evaluated. Tests results showed the use of steel slag aggregate (SSA) as full replacement of natural limestone aggregate could yield higher volume stability, improved compressive strength, smaller drying shrinkage and enhanced anti-freeze property of geopolymer concrete. Moreover, the activator of water glass was demonstrated to be superior to NaOH because free oxides in steel slag could be consumed in water glass solution. Discussion on the mechanism behind the superiority of BOF SSA in conjunction with alkalis was elaborated from the perspective of chemical reaction. The geopolymer matrix and interfacial transition zone (ITZ) were enhanced due to the diffusion of Ca ions to form the gel and densify the microstructure. Techniques of XRD, TGA, SEM/EDX were utilized for the analysis of the improved geopolymer matrix and strengthened ITZ. This research could facilitate the recycling and upgrading of steel slag for construction.

Nano-scale P, Zn-codoped reduced-graphene oxide incorporated epoxy composite; synthesis, electronic-level DFT-D modeling, and anti-corrosion properties

The great potential of the advanced nano-materials like graphene oxide as smart containers for the controlled desorption of the inhibitors and their effectiveness as dual active/passive anti-corrosive agents in the polymeric composites has been noticed in recent researches. In this work, aminotrimethylene phosphonic acid (AMP) was used with two primary purposes: a non-toxic reductant of GO and a potent chelating agent. Zinc cations were chelated with AMP on the reduced graphene oxide, forming a nanocontainer with active protection potency. The successful reduction of GO and AMP-zinc chelation were confirmed by FT-IR, Raman, TGA, and UV–visible analysis. The interactions between GO, AMP, and zinc cations were investigated by density-functional theory (DFT)-D computational modeling. The electrochemical analyses have proved the inhibitory potency of the P, Zn-codoped reduced-graphene oxide (GAZ) nanoparticle. The incorporation of the anti-corrosive nanocontainers into the epoxy coating covered the defects of the matrix significantly. It resulted in great protection of the coating after 10 weeks of coatings evaluation in the NaCl media. It was also found that a dense and protective complex of AMP and zinc cations was formed in the scratched zone of the polymeric matrix. This protective complex demonstrated the self-healing anti-corrosion potency of the fabricated nanoparticles.

Meso-scale modeling of concrete cracking induced by 3D corrosion expansion of helical strands

A meso-scale numerical model is established to simulate concrete cracking induced by the three-dimensional (3D) corrosion expansion of helical strands in the present study. A 3D corrosion expansion model is proposed to consider the longitudinal helix shape and transverse flower-like shape of the strand. The concrete in the model is considered as a three-phase composite material consisting of a mortar matrix, aggregate, and interfacial transition zones (ITZ) between the mortar matrix and aggregate. The rationality of the proposed model is validated, and the effects of the space helix structure and the lay length of the strand on corrosion-induced cracking are discussed. The results indicate that considering the space helix structure of a strand can effectively improve the prediction accuracy of strand corrosion-induced concrete cracking. The change in strand lay length has little effect on the critical corrosion loss of the initial damage occurrence. The critical corrosion loss at cover cracking increases with increasing strand lay length, whereas the corrosion-induced crack width decreases with increasing strand lay length.

3D mesoscopic analysis on the compressive behavior of coral aggregate concrete accounting for coarse aggregate volume and maximum aggregate size

For better understanding the compressive behavior of coral aggregate concrete (CAC) with different volume fractions and maximum aggregate sizes (MASs) for coarse aggregate, an all-sided mesoscopic investigation was performed using a novel 3D mesoscale model assuming concrete to be a three-phase composite material composed of coarse aggregate, mortar matrix and interfacial transition zone. The random characteristics of coarse aggregate in shape and spatial distribution were considered adequately in the mesoscale model. Fourteen types of cubic mesoscale models (sized by 100 × 100 × 100 mm3) with various aggregate volume fractions (0–67.4%) and MASs (10–30 mm), were established to study the quasi-static compressive behaviors of CAC, such as the deformation processes, failure patterns and stress–strain relations. By comparing the simulation results and the available test results, it has proven to be that the present 3D mesoscale modelling approach was capable of simulating and investigating the compressive behavior of CAC. Besides, it was indicated from the simulation results that the compressive strength of CAC generally decreases with the increase of MAS, but when the MAS exceeds the critical value, the varying trend of compressive strength tends to slow down. Additionally, the compressive strength tends to decrease before reaching a certain aggregate volume, but when it exceeds a certain volume, that is, the optimum aggregate volume, the compressive strength exhibits a rebounding trend. And the optimum aggregate volume of CAC with the MAS of 20 mm was determined from 58.0% to 61.1%. Furthermore, a regressive relation between concrete strength and aggregate volume was preliminarily derived from simulation and available test results, which can provide some enlightenments for the mix design and performance prediction of CAC.

Characterization of the Microstructure of the Cement-Rock Interface Using Environmental Scanning Electron Microscopy and Micro-Computed Tomography Scan

Summary Cement-rock interface is a major component of the wellbore barrier system. Leakage may result from the poor bonding between cement and rock interface. In this paper we investigate possible factors that may affect the cement-rock interface bonding. More specifically, integrity of the cement-rock interface was characterized using micro-computed tomography (CT) and environmental scanning electron microscopy (ESEM). Hollow cylinder rock samples were prepared by using rock samples (e.g., Banff dolostone, Pekisko limestone, Doig sandstone, Notikewin siltstone, Montney siltstone, and Wilrich siltstone) collected from different Alberta wells at various depths. Two abandonment cement blends were injected into the rock open hole. After curing the cement-rock samples in water at ambient temperature (≈21°C) and 1,500 psi for 7 days, the samples were then processed into thin sections. By using ESEM (0.05-µm resolution) and micro-CT (11.92-µm resolution) techniques, the 2D and 3D models of the cement-rock interface were developed. Energy-dispersive X-ray spectroscopy (EDS) was conducted to analyze chemical characteristic of the cement-rock samples. Using the CT images, computational fluid dynamics (CFD) models were built to simulate fluid flow through the cement-rock samples. For both cement and rock, there is a nonuniform porosity distribution in radial and axial directions. For most of the cement-rock samples, the highest porosity region in the cement column was found at the cement-rock interface. Optimizing the chemistry of the cement system enhances the cement-rock interface bond by effectively reducing the gap between cement and rock observed in ESEM images. Although cement migration was observed in the rough rock surface in porous rocks, the rock interface and matrix zones have almost identical element concentrations. For the investigated samples, the chance for significant chemical reaction at the cement-rock interface is minimal. CFD simulation based on digital cement models showed that the cement-rock interface has more chance to act as the main flow pathway when intact (low permeability) caprock exists. The sample preparation, image analysis and simulation methods used in this study can be also applied to other cement interface studies (e.g., cement-casing, casing-cement-rock). From the practical field application point of view, the results presented here would help to have a better understanding of the requirements for designing optimum cement formulations to establish effective zonal isolation and reduce the greenhouse gas emissions from oil and gas wells.

FORECAST EVALUATION OF HEAT PROTECTION AND MECHANICAL PROPERTIES OF INSULATING CONSTRUCTION CERAMIC MATERIALS

An integrated approach to determine the rational design of wall ceramic products based on modeling their behavior under operating conditions is proposed. This approach was used in the development of technology for heat–efficient insulating construction ceramic materials for energy–saving construction. For two models of porous–hollow ceramic products with a porous frame (40 % of voids) and a dense frame (60 % of voids), a predictive assessment of their heat–shielding and mechanical properties was carried out. Calculations of the equivalent coefficient of thermal conductivity of models based on Fourier’s law established that with a decrease in the voidness of products with a porous wall, the coefficient of their thermal conductivity decreases by 12 %, which improves the heat–shielding properties. Based on the results of computer simulation of the behavior of models under the influence of static power loads, it was determined that porosity of the ceramic framework of products leads to degradation of mechanical strength almost proportionally to a decrease in voidness. The stress–strain state of 3D models of ceramic structures with different pore geometry (spherical, globular, ellipsoidal) is analyzed and it is shown that stresses are concentrated in the contact zones of a ceramic matrix with pores. It is shown that the most durable is the structural model with spherical pores. The expediency of organizing such a structure, the need to strengthen the ceramic matrix of materials and zones surrounding the pores, as the most vulnerable structural sites, is shown. The results of predictive calculations have been experimentally confirmed in the development of technology for structural and heat–insulating composite–type ceramic materials based on low–melting loam and ash microspheres, which provide a given structural picture of the ceramic material.

The composition-dependent oxidation film formation in Mg-Li-Al alloys

The composition-dependent oxidation film formation behaviour in Mg-Li-Al alloys was investigated via diffusion couple experiments. The concentration gradients of alloying elements across the bonded interface resulted in both microstructural and oxidation behaviour changes. The interdiffusion of alloying elements led to four different matrix zones. Different oxidation behaviours in single-phase zones were caused mainly by Li concentration variations among them, specifically, higher Li contents bring about thicker oxide films. A thicker oxidation film induced by accelerated oxidation in the duplex diffusion zone was observed compared to those in the single-phase zones, which was a result of galvanic degradation.

Mesoscopic simulation on flexural behavior of single-way reinforced concrete slab with rebars subjected to localized corrosion

Corrosion reduces cross-section area of rebar and bond between the rebar and concrete, which leads to the degradation of durability of structure. In this study, a three-dimensional mesoscopic numerical analysis model was established to explore influence of localized corrosion on behavior of single-way RC slab. In the model, concrete was considered as a tri-phase composite consisted of coarse aggregate particles, mortar matrix and interface transition zones (ITZs). The effect of corrosion was simulated by reducing cross-section area of rebar and bond. Localized corrosion of reinforcement was taken into account and non-linear spring element was adopted to describe interaction between concrete and reinforcement. The simulation results for corrosion RC slab are in good agreement with test result in terms of ultimate flexural capacity and displacement. On this basis, the flexural behavior of corroded single-way RC slab under fourth-point bending condition was simulated and analyzed whilst the influence of corrosion level, concrete strength, rebar type and diameter was investigated. Simulation results indicate that flexural bearing capacity of corroded RC slab increases when reinforcement was minor corroded and decreases for a further increasing corrosion level. The effect of concrete strength on bearing capacity of slab is insignificant with the increase of corrosion level. The RC slabs with plain rebar break in brittle failure when corrosion level is over 7.5%. However, slab with deformed rebar fail in a ductile pattern in this case. Under fourth-point bending condition, energy dissipation of RC slabs with larger reinforcement ratio decreases faster. The influence of reinforcement ratio and bond at rebar-concrete interface caused by the variation of rebar diameter is still significant when the rebar is corroded.

Loading rate effects on the properties of fiber-matrix zone surrounding steel fibers and cement based matrix

This study investigated the loading rate effects on the properties of fiber–matrix zone (FMZ) surrounding steel fibers by conducting nanoindentation tests. Ultra-high performance concrete (MU) produced the highest loading rate sensitivity (n) owing to the highest pressure hardening sensitivity of MU although both hardness (H) and Young’s modulus (E) of FMZ of other two matrices also clearly increased as loading rate increased from 1 to 8 mN/s. The higher n of MU would be based on the higher content of ultra-high density calcium silicate hydrate. The C-S-H with higher calcium to silica ratio generated higher rate sensitivity.

Effects of maternal diazinon exposure on frontal cerebral cortical development in mouse embryo

Background Diazinon including organophosphate (OP) that is widely used in agriculture and animal husbandry industry and the risk of human infection with the toxin and their toxicity. Methods Pregnant balb/c mice (30–35 g) were randomly divided into five groups of five: the control group (no intervention), two sham groups (emulsifier 0.52, and 5.2 liters/volume). From the seventh to the eighteenth day of pregnancy, two experimental groups received diazinon inhaled 1.3 (EXP1) and 13 liters/volume (EXP2) for 40 min every other day, respectively. On the 18th day of pregnancy, the animals were killed and their embryos were removed to appraisal the growth of fetus and development of the frontal cortex. A computer-assisted morphometric quantitative images analysis were performed on the frontal cerebral cortex (FCC) including cortical plate (CP), intermediate zone (IZ) and matrix (proliferative) zone (MZ) of the mouse embryos. Findings The average of crown-rump length and weight of the embryos in the experimental groups were increased without any significant difference. The mean fetal FCC thickness in the EXP2 group was significantly reduced compared to the control group, CP thickness was remarkably increased in fetuses exposed to diazinon. Comparing the mean thickness of MZ and IZ in EXP groups with the sham and control groups indicated a significant decrease. The positive K-67 cells in the FCC of the EXP2 group were significantly reduced. Discussion Exposing diazinon during pregnancy can reduce brain development and would be neurotoxic to the developing brain and can lead to behavioral changes in the offspring.

Tsai–Wu based orthotropic damage model

This paper presents a novel approach concerning the development of an orthotropic damage model for composite materials, based on the original plane stress Tsai–Wu failure criterion. In its original formulation, the Tsai–Wu is a mode-independent criterion only capable of acknowledging the existence of damage in a certain point of a composite material. It is not capable of identifying if the damage is located in the fibre, matrix or interlaminar zone. This study aims at filling this gap in knowledge by providing a simple method, based on equivalent stresses and strains, that identifies the relevant failure modes when the Tsai–Wu failure criterion is at the onset of damage. Using this novel methodology, it is possible to implement classical damage evolution constitutive laws based on the fracture energy regularization. At present, the proposed damage formulation is based on the consideration of a plane stress space and Mode I fracture, but its generalization to a full 3D damage model is expected to be defined in the near future. The damage model is implemented in the commercial finite element software ABAQUS through a user-defined material (UMAT) subroutine, and all numerical models are compared with experimental results available in the literature.

Size-dependency of the transverse-tensile failure behavior for triaxially braided composites

Coupon specimens of triaxially braided composites suffer significant out-of-plane tension–torsion coupled deformation along the free edges, known as free-edge effect, under uniaxial tensile/compressive loading. The presence of free-edge effect causes variations in the measured stiffness and strength properties with specimen size. In this study, the size-dependent failure behavior of a single-layer triaxially braided composite under transverse tension load is investigated. Experiments are conducted to characterize the stress–strain response and failure pattern of straight-sided coupon specimens with various widths. Digital image correlation is used to monitor the free-edge-effect–induced tension-torsion coupled deformation. An improved meso-scale finite element model is developed to enable simulation of fiber bundle pull-out failure by introducing a fully covered tow-to-tow interface and plastic failure of the pure matrix zone. The model captures the size-dependent stress–strain response, free-edge effect induced premature failure and ultimate failure phenomena of the braided composite. The experimental and numerical results identify the transition of the failure mechanism from one that is dominated by fiber bundle pull-out to one that is dominated by fiber bundle shear as the specimen width is increased. The numerical simulation results reveal the correlation of free-edge effect with the progressive failure behavior, and they aid in identifying the major stress components that are contributing to the failure. The conclusions provide useful insights for the structural design and architecture optimization of triaxially braided composites.

Application of meso-scale finite-element method to strength and size effect of concrete

An analytical study on the compression, tension and shear strengths of concrete and corresponding size effect is conducted using the meso-scale finite-element method (FEM). Prior to the analysis, a method of defining concrete as a meso-scale composite and multi-phase is described. The concrete is assumed to be a composite with three phases: aggregates, cement matrix and interfacial transition zone. The material properties of each phase are applied. Behaviours relating to uniaxial and flexural compressive failure, splitting and direct tensile failure of concrete, and shear failure of reinforced concrete are analysed using the model constructed; the size effect is confirmed through these analyses. The performance of the analytical models is also evaluated by comparing experimental with analytical results. Finally, it is confirmed that the application of the meso-scale size analysis model is enough when studying the occurrence and progress of tensile cracks. This basic study represents a fresh application of meso-scale FEM analysis to concrete; in future research, the authors will apply meso-scale FEM analysis in a wider variety of fields.

Particle distribution-dependent micromechanical simulation on mechanical properties and damage behaviors of particle reinforced metal matrix composites

A micromechanical simulation has been performed to study the effect of particle distribution on the mechanical properties and damage behaviors of particle reinforced metal matrix composites (PRMMCs). Two-dimensional (2D) representative volume elements with variable particle size, volume fraction and particle distribution were generated and subjected to finite element simulation. An enhanced continuum model, which incorporates dislocation punching effect at particle-matrix interfaces and Taylor-based nonlocal theory of plasticity in matrix, was used to simulate the mismatch in coefficients of thermal expansion strengthening and particle size-dependent strengthening. Additionally, constitutive damage behaviors were involved in simulating the crack initiation and evolution, considering the ductile damage in matrix and dislocation punching zone, as well as the particle cracking. Simulation results indicate that refining the particle size is helpful to improve the tensile strength and fracture resistance of PRMMCs, whereas the increase of particle clustering volume fraction or severity facilitates damage evolution and deteriorates the mechanical properties. Statistical analysis indicates a negative linear dependence between particle distribution homogeneity and the ductility, given a constant particle size and volume fraction.