Interpenetrating Phase Composites Research Articles

Influence of nanodiamond on compressive and dry-sliding wear behaviors of Al2O3–Al interpenetrating-phase composites

In this research, the effects of nanodiamond (ND) addition at different loadings on the compressive and wear properties of the interpenetrating phases hybrid aluminum/alumina (Al/Al2O3) composite were investigated. The samples were fabricated in a two-step process. First, the Al2O3-ND preforms were fabricated via the replica method. Second, the squeeze casting route was employed to infiltrate the molten pure Al. The ceramic preforms were made by immersing a polyurethane foam with 17 ppi pores in a slurry containing α-Al2O3 powder (1 μm), ND particles (0–10 vol%), and natural egg white. After sintering at 1500 °C for 4 h, the preheated preforms were infiltrated with molten Al. The microstructural evaluations of the preforms and composites revealed a proper distribution of the ND particles in the preform, as well as the formation of the ND agglomerates at higher volume percentages. Also, the hardness of the samples enhanced with an increase in the ND loading, reaching a maximum of 263.8 Vickers for the 10 vol% ND-loaded composite. The compressive strength of the samples enhanced up to 3 vol% ND addition and then decreased due to the agglomeration. The wear test results indicated that the best behavior was related to the 3 vol% ND-loaded composite. Embedding the 3 vol% ND decreased the weight rate and friction coefficient of the interpenetrating phases hybrid Al/Al2O3 composite by 16 % (from 8.2396×10−3 to 6.9269×10−3 mm3/m) and 12 % (0.8165 to 0.7238), respectively. The study of the worn surfaces of the samples after wear testing revealed that the dominant wear mechanisms were abrasive and adhesive for the higher and lower volume fractions of the ND, respectively.

Compressive Properties and Failure of Aluminum/Epoxy Resin Interpenetrating Phase Composites Reinforced by Glass Fiber

Compressive Properties and Failure of Aluminum/Epoxy Resin Interpenetrating Phase Composites Reinforced by Glass Fiber

Porous titanium/hydroxyapatite interpenetrating phase composites with optimal mechanical and biological properties for personalized bone repair

This study introduces the first fabrication of porous titanium/hydroxyapatite interpenetrating phase composites achieved through an innovative processing method. The approach combines additive manufacturing of a customized titanium skeleton with the infiltration of an injectable hydroxyapatite foam, followed by in situ foam hardening at physiological temperature. This biomimetic process circumvents ceramic sintering and metal casting, effectively avoiding the formation of secondary phases that can impair mechanical performance. Hydroxyapatite foams, prepared using two foaming agents (polysorbate 80 and gelatine), significantly reinforce the titanium skeleton while preserving the microstructural characteristics essential for osteoinductive properties. The strengthening mechanisms rely on the conformation of the foams to the titanium surface, thereby enabling a stable mechanical interlocking and effective interfacial stress transfer. This, combined with the mechanical constriction of phases, enhances damage tolerance and mechanically reliability of the interpenetrating phase composites. In addition, the interpenetrating phase composites feature a network of concave pores with an optimal size for bone repair, support human osteoblasts proliferation, and exhibit mechanical properties compatible with bone, offering a promising solution for the efficient and personalized reconstruction of large bone defects. The results demonstrate a significant advancement in composite fabrication, integrating the benefits of additive manufacturing for bone repair with the osteogenic capacity of calcium phosphate ceramics.

Compressive Properties and Fracture Behaviours of Ti/Al Interpenetrating Phase Composites with Additive-Manufactured Triply Periodic Minimal Surface Porous Structures

Compressive Properties and Fracture Behaviours of Ti/Al Interpenetrating Phase Composites with Additive-Manufactured Triply Periodic Minimal Surface Porous Structures

Compressive and flexural properties and damage modes of aluminum foam/epoxy resin interpenetrating phase composites reinforced by silica powder

AbstractInterpenetrating phase composites (IPCs) can combine the advantages of each component and have a good application prospect. IPCs were prepared by combining open‐cell aluminum foam (AF) and epoxy resin (EP) in three‐dimensional space in this study. Different contents of silica powder (SP, 80, 100, 120, and 140 wt%) were added to EP to improve the compressive and three‐point bending properties of IPCs. In the bending test, acoustic emission (AE) was applied to track the bending deformation of the samples, and k‐means clustering algorithm was applied to identify the damage modes. The compressive and bending properties of IPCs increased first and then decreased with the increase of SP content, and reached the maximum when the SP content was 100 wt%, with a compressive yield strength of 74.6 MPa and a bending peak load of 1.96 kN. The performance degradation was mainly attributed to the AF/EP debonding due to SP distribution at the interface. The X‐type shear band and EP/AF debonding appeared in compression failures of AF and IPCs, respectively. The AE clustering results showed that under bending load, plastic deformation of matrix (60–200 kHz) and fracture failure (230–340 kHz) modes appeared in AF, while EP/AF debonding (60–120 kHz), EP failure (120–230 kHz) and plastic deformation of foam matrix (230–250 kHz) modes appeared in IPCs.Highlights Silica powder was added to improve compressive and bending properties of IPCs. Acoustic emission was used to monitor bending of foam and IPCs firstly. k‐means clustering was used to identify and classify bending damage patterns.

Correlation structures of statistically isotropic stiffness and compliance TRFs through upscaling

This paper reports a procedure to develop random fields of material properties on a mesoscale level, coarser than the microscale level of heterogeneous material microstructure. Since the anisotropy of properties at the mesoscale level is unavoidable, tensor-valued random fields (TRFs) need to be constructed. The construction satisfies three criteria: (i) the passage from the micro to mesoscale must be conducted according to micromechanics, (ii) any anisotropic properties must be grasped, and (iii) full (spatial) correlation structure must be accounted for. The construction is illustrated in the example of a linear elastic microstructure modeling a planar interpenetrating phase composite (IPC), where each phase is interconnected throughout the microstructure. The most general representation of a statistically homogeneous and isotropic correlation structure of the TRFs of stiffness and compliance is employed. Four material functions of the representation are determined through scale-dependent homogenization, which grasps any auto- and cross-correlations within/among different components of TRFs. The Gaussianity of the TRFs is also assessed with a finding that, overall, the smaller is the mesoscale and the more pronounced is the microstructural randomness, the more non-Gaussian are the mesoscale TRFs.

Tensile properties and damage mechanisms of 3D printed Ti-24Nb-4Zr-8Sn alloy and polyurea interpenetrating phase composites

By preparing interpenetrating phase composites (IPCs) using two-phase composites of metals and polymers, it is possible to preserve the inherent properties of the metal lattice while leveraging the exceptional characteristics of polymers. In this study, a Ti2448/polyurea composite with continuous interpenetrating phase was fabricated by infusing polyurea into a cross-laminated lattice prepared using electron beam melting (EBM) technology. The IPCs exhibit a tensile strength of 91 MPa, representing a 14 % increase over the theoretical strength. Moreover, the maximum hysteresis loss energy measures 349 J/m³, representing about ∼102 % increase over the maximum hysteresis loss energy of the lattice. The damage and failure modes of IPCs under tensile loading was revealed by finite element analysis. Our results would provide important data and valuable insights to advance the development of IPCs.

Superior damage tolerance observed in interpenetrating phase composites composed of aperiodic lattice structures

Interpenetrating Phase Composite (IPC) metamaterials, based on lattice topologies, have garnered significant attention as advanced materials for structural applications. However, conventional IPCs, which rely on periodic lattice unit cells, are prone to catastrophic failure due to their global deformation modes. To overcome this limitation, we present a novel IPC design utilizing aperiodic truss unit cells, inspired by the elusive “Einstein” monotile pattern. Our concept is demonstrated through IPC 3D printed via polymer jetting, using a hard polymer as the lattice filler and a soft polymer as the matrix. The distinctive mechanical properties of IPCs are characterized through single and cyclic quasi-static compression testing. Our findings demonstrate that aperiodic IPCs enable progressive deformation with gradual compression stress plateaus. Additionally, aperiodic IPCs exhibit remarkable damage tolerance, retaining 67.59 % of residual energy absorption and 73.83 % of ultimate strength after multiple cyclic compressions up to 30 % strain. These mechanisms are attributed to the synergistic deformation of interconnected unit cells, which lead to self-adjusting plastic collapse, progressive displacement evolution and delocalized deformation. This aperiodic concept paves the way for developing high-performance cushioning protection materials.

Mechanical evaluation of multi-continuous interpenetrating phase composites based on Schwarz Primitive cellular structure

Interpenetrating phase composites (IPCs) have been extensively promoted due to their robust mechanical properties. To further obtain the enhanced properties and elucidate the underlying mechanical mechanism, we designed and manufactured the tri-continuous IPCs by filling hyperelastic PDMS into a 3D-printed Schwarz Primitive (P) cellular skeleton based on the viscoplastic polymer. Subsequently, the compressive properties, cyclic properties, and relaxation properties of the IPCs were experimentally investigated. Results demonstrated that interpenetrating can improve the compressive properties, reduce the relaxation behavior, and weaken the cyclic softening effect. By incorporating a user material subroutine in simulations, we analyzed the deformation behaviors of P cellular material and IPCs. Through a combination of experimental observations and simulated outcomes, we refined our understanding of the deformation mechanism of IPCs. Our analysis revealed that filled PDMS played a positive role in enhancing the mechanical performance of TC-IPCs through three key mechanisms: Firstly, it shears part of the external load of TC-IPCs. Secondly, it astricts the bending deformation in the skeleton, thereby preventing the stress drop induced by buckling. Thirdly, the interaction between PDMS and P cellular skeleton puts them in compressive stress in tri-direction, enhancing the overall mechanical properties. These findings contribute to advancing the development and application of IPCs.

Ceramic/metal composites fabricated via 3D printing and ultrasonic-assisted infiltration for high specific strength and energy absorption

To address the strength-toughness dilemma, ceramic/metal interpenetrating phase composites (IPCs), fabricated through metal infiltration into ceramic perform, have been investigated. However, infiltrating metal into porous ceramic scaffold with high volume fraction remains a significant challenge. Herein, we propose a novel method to fabricate highly dense Al2O3/AlSi10Mg (Al) interpenetrating phase composites through ultrasonic-assisted pressureless infiltration into 3D printed ceramic scaffolds. Experimental results indicate that the as-fabricated Al2O3/Al IPCs exhibit excellent quasi-static and dynamic mechanical properties. Specifically, the materials can achieve high specific compressive strengths of 148.6 ± 5.2 MPa/(g/cm3) under quasi-static compression and 228.6 ± 4.5 MPa/(g/cm3) under dynamic compression while also exhibiting high specific energy absorption of 33.6 ± 0.9 J/g under quasi-static compression and 37.7 ± 1.1 J/g under dynamic compression. The specific compressive strength and specific energy absorption of the as-fabricated Al2O3/Al IPCs outperform those of the literature-reported ceramic/metal IPCs. This work provides an innovative approach to fabricate strong and tough ceramic composites.

Strengthening mechanism of TPMS interpenetrating phase composites for bone tissue engineering

Multicomponent functional scaffolds hold great promise as implanted materials with compatible mechanical properties and biological functionalities. Interpenetrating phase composites (IPCs) with biomimetic multiscale porosity were fabricated in this study by additive manufacturing and foaming processes using polymethyl methacrylate (PMMA) and polyurethane foam (PUF), respectively. PMMA creates the macroscopic pores with triply periodic minimal surface (TPMS) structures, while PUF forms microscale porosity interpenetrating within the scaffolds, which has been confirmed by SEM and CT tests. Mechanical testing and finite element analysis (FEA) demonstrated significant enhancements in peak strength, toughness, and energy absorption of the IPCs compared to the scaffold alone, with increases of 134%, 73%, and 236%, respectively. The FEA provided insights into the failure and strengthening mechanisms of the interpenetrating porous structure. The continuous PUF component integrated within the IPCs effectively facilitated stress transfer, impeded crack propagation, and significantly prolonged the stress plateau of the scaffolds. Meanwhile, the PMMA primarily served as the main mechanical load-bearing component, transferring stress to the PUF during the deformation stage, resulting in a highly uniform stress distribution within the scaffolds. This uniform stress distribution creates an environment conducive to effective stress stimulation of the internally growing tissue.

Insights into morphology and mechanical properties of architected interpenetrating aluminum-alumina composites

Additive manufacturing (AM) technologies are unleashing the restrictions imposed by conventional manufacturing, allowing the production of innovative designs tailored to improve properties or performance. AM techniques in ceramic production allow the application of novel designs to ceramic parts, opening new opportunities for combining technologies aiming to obtain architected interpenetrating phase composites (IPCs). In this study, alumina structures with different architectures and Computer Aided Design (CAD) structure porosity oriented unidirectionally or bidirectionally, were fabricated by vat photopolymerization technique, namely Digital Light Processing. Afterwards, these structures were infiltrated with an aluminum alloy through investment casting, thus obtaining aluminum-alumina IPCs. Under compression, the IPCs presented a ductile behavior, conversely to the fragile ceramic counterparts. The IPCs compressive strength and absorbed energy were expressively higher than their ceramic counterparts. Comparing the bidirectional IPCs with the unidirectional ones, a significant increase in compressive strength and absorbed energy was observed, from 36.2% to 42.3% and from 164.8% to 358.1%, respectively, due to the greater amount and interconnection of the metal inside the ceramic structure. This study demonstrates the feasibility of this manufacturing route, combining two distinctive technologies, for the fabrication of metal-ceramic architected IPCs, allowing to tailor their mechanical properties and energy absorption capacity for a given application.

Interpenetrating LiB/Li3BN2 phases enabling stable composite lithium metal anode

Host-less lithium metal anode generally suffers from large volume changes and serious dendrite growth during cycling, which poses challenges for its practical application. Interpenetrating phase composites with continuous architectures offer a solution to enhance mechanical properties of materials. Herein, a robust composite Li anode (LBN) material is fabricated through the metallurgical reaction between Li and hexagonal boron nitride (h-BN) with the formation of interpenetrating LiB/Li3BN2 phases. As LiB fibers are anchored by Li3BN2 granules, the collapse and slippage of LiB fibers are suppressed whilst the mechanical strength and structural stability of LBN are reinforced. By rolling, ultrathin (15 μm), freestanding, and electrochemically stable LBN foil can be obtained. The LBN anode exhibits a high average Coulombic efficiency of 99.69% (1 mA cm−2, 3 mAh cm−2) and a long lifespan of 2500 h (1 mA cm−2, 1 mAh cm−2). Notably, the LiCoO2 (with double-sided load 40 mg cm−2)|LBN pouch cell can operate over 450 cycles with a capacity retention of 90.1%. The exceptional cycling stability of LBN can be ascribed to the interpenetrating reinforcement architectures and synergistic electronic/ionic conductivity of the LiB/Li3BN2 dual-lithiophilic-phases. This work provides a new methodology for thin Li strip processing and reinforced-architecture design, with implications beyond battery applications.

ANISOTROPY AND MECHANICAL CHARACTERISTICS OF ULTRA-HIGH PERFORMANCE CONCRETE AND ITS INTERPENETRATING PHASE COMPOSITE WITH TRIPLY PERIODIC MINIMAL SURFACE ARCHITECTURES

Abstract This work numerically explores the anisotropy, impact phase wave propagation, buckling resistance, and natural vibration of ultra-high performance concrete (UHPC) and UHPC-steel interpenetrating phase composite (IPC) with triply periodic minimal surfaces (TPMSs), including sheet and solid Gyroid, Primitive, Diamond, and I-WP. The experiment is conducted verifying the accuracy of the numerical model in terms of Young's modulus of polylactic acid (PLA)-based TPMS lattices and PLA-cement IPCs with TPMS cores, with the highest percent difference of 15% found for IPCs and 17% found for lattice. The results indicate that UHPC material with sheet Gyroid exhibits the least extreme anisotropy in response to the varying orientation among other lattices regardless of the change of solid density, making it the ideal candidate for construction materials. Interestingly, compared to UHPC-based TPMS lattice, IPCs possess a much smaller anisotropy and exhibit almost isotropy regardless the variation of solid density and TPMS topology, offering a free selection of TPMS type to fabricate IPCs without much care of anisotropy. The phase wave and buckling resistance of UHPC- and IPC-based beams with TPMSs nonlinearly decrease with a drop of TPMS solid density, but it is the almost linear pattern for the case of natural vibration frequency. UHPC material and IPC with sheet Gyroid lattice are found to possess the lowest phase wave velocity and exhibit the least anisotropy of wave propagation, showing it as an ideal candidate for UHPC material to suppress the destructive energy induced by the external impact.

Unprecedented Strength Enhancement Observed in Interpenetrating Phase Composites of Aperiodic Lattice Metamaterials

AbstractSimultaneous high strength and high toughness are highly sought‐after in lattice metamaterials, but these properties are typically mutually exclusive. To overcome this challenge, the development of interpenetrating phase composite (IPC), which incorporates a net matrix infill into the lattice, has shown great potential in overcoming these constraints and is thus of continuous practical interest. In this work, a novel aperiodic monotile truss lattice and polymer IPC that exhibit unprecedented enhancement in both strength and toughness are reported. Specifically, the aperiodic unit cell is inspired by Einstein's monotile, a single space‐filling shape where the cell orientation never repeats. The IPCs are achieved through 3D‐printed Ti‐6Al‐4V truss lattices and epoxy infiltration. The highest gain in compressive strength reveals an impressive 246.61% increase, significantly exceeding the “1 + 1 > 2” idealization typically associated with strength in IPC metamaterials. Furthermore, a high specific energy absorption of 46.2 J g−1 demonstrates superior toughness. The underlying mechanisms, including damage sequences, two‐phase interactions, and geometric effects between truss and epoxy, are fully elucidated. Overall, this work reports unprecedented enhancement in IPC's properties and demonstrates the potential of utilizing idealized structures to achieve an optimal combination of strength and toughness in mechanical metamaterials.

Mechanical properties of Al–Si alloy/Si3N4 interpenetrating phase composite based on a preform fabricated at 1200 °C

Interpenetrating phase composites with three-dimensional co-continuous architecture are promising materials for advanced structural applications due to their excellent combination of properties. In this work, a novel and low-cost Al–Si alloy/Si3N4 IPC was fabricated via squeeze infiltration of Al11Si alloy melt into a porous Si3N4 preform manufactured at a low temperature of 1200 °C using H3PO4 as pore-former and binder. Microstructures of IPC show a good infiltration quality and strong interfacial bonding between metal and ceramic phases without any intermediate reaction products. The fabricated IPC exhibited significantly higher specific hardness and stiffness than the Al11Si alloy. Moreover, an excellent damage tolerance, a substantial increase in compressive strength of 420 %, flexural strength of 168 %, and a significant reduction in wear rate of 95 % in the IPC was achieved with respect to Al11Si. The flexural strength and fracture toughness values of the fabricated IPC compare well to values of Al alloy/Si3N4 IPCs reported in the literature, despite being processed using a porous Si3N4 preform fabricated at a much lower temperature.

Effect of TPMS reinforcement on the mechanical properties of aluminium–alumina interpenetrating phase composites

AbstractTriply Periodic Minimal Surface (TPMS)-based aluminium–alumina Interpenetrating Phase Composites (IPCs) manufactured through the combination of Additive Manufacturing (AM) and investment casting are explored in this study. Multiple alumina TPMS structures (Gyroid, Diamond, and Primitive) with different geometries and volume fractions were designed and fabricated using Digital Light Processing (DLP) AM technology. Afterwards, these ceramic structures were filled with an aluminium alloy via investment casting, uncovering an aluminium–alumina IPCs. A global characterization was performed, including ceramics shrinkage and mass loss; specimens’ morphology; chemical and crystalline characterization; density analysis and mechanical testing. Overall, DLP technology was found effective for producing these highly complex ceramic structures, with high surface quality. The sintered alumina structures presented a relative density of ca. 76.3% and a pseudo-ductile layer-by-layer failure behaviour, with Diamond-based TPMS exhibiting the highest compressive strength. Regarding the IPCs, the addition of aluminium significantly changed the compressive behaviour of the samples, presenting an energy absorption behaviour. The integration of the alumina phase into the aluminium alloy led to an improvement on the compressive offset stress of approximately 6% when compared to the aluminium alloy used. Diamond and Gyroid IPCs demonstrated similar mechanical behaviour and the highest mechanical performance. Graphical Abstract

Thermal conductivity of Al/AlN interpenetrating phase composites with different preform porosity

In this investigation, the thermal conductive (TC) properties of the Al/AlN interpenetrating phase composites (IPCs) with varying preform porosity at different temperatures (20°C to 200°C) were studied. The TC values obtained through experimentation were compared to predictions generated by analytical models. IPCs with higher preform porosity exhibit higher TC. The TC of IPCs exhibits an inverse temperature dependence. Theoretical models accurately predict the thermal conductivity of IPCs with high preform porosity.

Entangled metallic porous material–silicone rubber interpenetrating phase composites with simultaneous high specific stiffness and energy consumption

High stiffness and superior energy consumption have consistently been primary research focuses in the field of damping materials. Hence, this work presented an innovative interpenetrating phase composite (IPC) crafted from wound elastic entangled metallic porous material and silicone rubber. The proposed composite effectively integrates the unique properties of the original materials, showcasing a seamless blend. Dynamic experimental tests were conducted to analyze the dynamic compression mechanical behavior of the composites, revealing that the composites exhibit excellent energy consumption capabilities and elevated stiffness characteristics. The improvement in both stiffness and damping characteristics is attributed to the addition of silicone rubber, which solidifies the structure of the composites. The introduction of interfacial friction results from maintaining compression, sliding, and other frictional interactions among the original spiral coils. Notably, the composites also display exceptional fatigue resistance. Overall, this work demonstrates the potential to concurrently achieve enhanced stiffness and superior energy consumption through the use of entangled metallic porous material and silicone rubber.

Mechanical performance of interpenetrating phase composites with multi-sheet lattice structures

Interpenetrating phase composites (IPCs), as a novel type of composite material, offer advantages such as lightweight, high strength, and superior energy absorption. This study proposed a multi-sheet lattice structure based on the Gyroid surface, which was initially designed and then fabricated via TC4 laser powder bed fusion (LPBF). Through the infiltration of epoxy resin, a composite material with interpenetrating phases was achieved. Subsequently, the mechanical properties of the IPCs were comprehensively investigated using experimental and numerical simulation methods. In quasi-static compression tests, the IPCs demonstrated higher strength and improved energy absorption characteristics compared to original lattice structures. However, under dynamic loading conditions, while the strength of the IPCs showed significant enhancement, the improvement in energy absorption characteristics of the composite structures was constrained by temperature rise, thermal softening effects, and the glass transition of the epoxy resin induced by elevated temperatures. Thus, while the proposed IPCs exhibited high strength under both quasi-static and dynamic loads, it is imperative to consider material properties and the influence of temperature on energy absorption to prevent overestimation of performance under dynamic loading conditions. Therefore, this study not only highlights the novelty of utilizing a multi-sheet lattice structure based on the Gyroid surface for creating IPCs, but also underscores the importance of carefully considering temperature effects on material properties when evaluating their performance under dynamic conditions.