The mechanical response of interpenetrating phase composites (IPCs) with stochastic spinodal topologies is investigated experimentally and numerically. Model polymeric systems are fabricated by ...Polyjet multi-material printing, with the reinforcing phase taking the topology of a spinodal shell, and the remaining volume filled by a softer matrix. We show that spinodal shell IPCs have comparable compressive strength and stiffness to IPCs with two well-established periodic reinforcements, the Schwarz P triply periodic minimal surface (TPMS) and the octet truss-lattice, while exhibiting far less catastrophic failure and greater damage resistance, particularly at high volume fraction of reinforcing phase. The combination of high stiffness and strength and a long flat plateau after yielding makes spinodal shell IPCs a promising candidate for energy absorption and impact protection applications, where the lack of material softening upon large compressive strains can prevent sudden collapse. Importantly, in contrast with all IPCs with periodic reinforcements, spinodal shell IPCs are amenable to scalable manufacturing via self-assembly techniques.
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•Alumina truss-microlattice and epoxy-infilled interpenetrating-phase composites.•High strength and long plateau stress for energy absorption.•Enhanced toughness of alumina when ...embedded in the epoxy.•Synergistic co-reinforcement in strength of the two phases.
Being lightweight, strong, and tough, are qualities often sought-after in practical engineering materials. Herein, we present interpenetrating phase composites (IPC), based on the combination of additively manufactured alumina microlattices and infiltrated epoxy, that display an excellent combination of such characteristics. Experimental and simulation studies on the compressive behaviours of different truss-microlattices and their functionally-graded variants have been carried out. Lengthened stress plateau up to −0.6 strain and co-enhanced strength up to 65 % higher than the linear sum of their constituents have been observed. This constitutes a simultaneous high specific strength and specific energy absorption up to 113.5–142.6 MPa/(g/cm3) and 25.3–35.6 J/g, respectively, for the IPCs, at low densities of around 1.8 g/cm3. The mechanism of the co-enhanced strength attribute to the improved alumina fracture toughness whilst the lengthened plateau attributes to the progressive material failure and strain energy relaxation. Overall, this work demonstrates the potential of using a strong ceramic and epoxy to achieve simultaneously high specific strength and energy absorption.
In this work, Al/AlN interpenetrating phase composites (IPCs) was fabricated by infiltrating the alloy melt into AlN preform via low pressure casting method. Open cell porous AlN preforms, fabricated ...via the slurry infiltration method, and have four different preform porosity were used for IPCs fabrication. The microstructures of porous AlN preforms and Al/AlN interpenetrating phase composites were characterized using scanning electron microscopy (SEM). The phase compositions of preforms and composites were analyzed by X-ray diffraction (XRD). The interface between AlN and Al matrix was found to have no visible defects, indicating good interfacial bonding. Compression tests were conducted, and the results showed that the material strength and toughness increased with increasing porosity. Additionally, the composites changed from brittle fracture to ductile fracture. Nanoindentation tests indicate that an increase in AlN content enhances the hardness of the IPCs components.
•Al/AlN IPCs with various preform porosity was fabricated by slurry infiltration and low-pressure casting method.•Relative density plays a pivotal role in determining the energy absorption properties of materials.•Nano hardness has a strong dependence on preform porosity.
For composite materials applied for energy absorption and vibration/noise reduction, it is of particular significance to clarify the role of strain rate and temperature on their mechanical ...properties. Here we present a study on the effects of strain rate (from 10−3 s−1 to 1 s−1) and temperature (from room temperature to 350 °C) on the compressive properties of a 3-D printed Mg–NiTi interpenetrating-phase composite, which features high energy absorption efficiency and good damping capacity. Within the regimes of strain rate and temperature, the composite constantly exhibits a stable stress plateau on the stress-strain curves, yet displays markedly different damage mechanisms depending on the specific strain rate and temperature. The 3-D interpenetrating-phase architecture promotes an effective stress transfer in the composite and resists the propagation of local damages, thereby conferring a high strengthening efficiency and outstanding damage tolerance. The unique combination of mechanical properties makes the composite appealing for applications under various conditions, especially for absorbing mechanical energy and reducing vibrations and noise.
•Entangled metallic porous material–silicone rubber interpenetrating phase composites.•Damping materials with both high stiffness and energy consumption.•Interfacial friction enhances mechanical ...properties.•Attractive fatigue resistance characteristics.
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.
Abstract Objectives To determine and identify correlations between flexural strength, strain at failure, elastic modulus and hardness versus ceramic network densities of a range of novel ...polymer-infiltrated-ceramic-network (PICN) materials. Methods Four ceramic network densities ranging from 59% to 72% of theoretical density, resin infiltrated PICN as well as pure polymer and dense ceramic cross-sections were subjected to Vickers Indentations (HV 5) for hardness evaluation. The flexural strength and elastic modulus were measured using three-point-bending. The fracture response of PICNs was determined for cracks induced by Vickers-indentation. Optical and scanning electron microscopy (SEM) was employed to observe the indented areas. Results Depending on the density of the porous ceramic the flexural strength of PICNs ranged from 131 to 160 MPa, the hardness values ranged between 1.05 and 2.10 GPa and the elastic modulus between 16.4 and 28.1 GPa. SEM observations of the indentation induced cracks indicate that the polymer network causes greater crack deflection than the dense ceramic material. The results were compared with simple analytical expressions for property variation of two phase composite materials. Significance This study points out the correlation between ceramic network density, elastic modulus and hardness of PICNs. These materials are considered to more closely imitate natural tooth properties compared with existing dental restorative materials.
This paper presents a study on mechanical response of porous aluminum skeleton/rigid polyurethane foam interpenetrating phase composites (IPCs) at different strain rates. Mechanical properties and ...failure mechanisms of IPC were identified. Results shown that the strain rate sensitivity of IPC is mostly caused by foamed filler while the deformation mechanisms are still dominated by aluminum skeleton. The aluminum skeleton exhibited lower total energy absorption at high strain rates because of the decrease in dynamic compressibility. However, the two constituent phases simultaneously contributed their high toughness and outstanding dynamic response to the IPCs. Also, compared with IPCs composed of solid polymers, the foamed filler significantly improved the compressibility, mechanical properties and strain rate sensitivity of IPCs. The suggested constitutive model adequately captured dynamic response of IPCs by comparisons with experiments. All results show that the metallic/polymeric interpenetrating phase composite foam is of high potential in energy dissipation and impact protection.
•Interpenetrating phase composites (IPCs) based on aluminum skeleton and rigid polyurethane foam was fabricated.•Porous materials benefit a lot by filling with polymer foams in energy absorption and shock resistance.•The foamed filler largely improved dynamic properties of IPCs without decreasing the compressibility.•Metallic skeleton dominated deformation behavior while the strain rate effect is ismore dependent on the polymer.•The suggested constitutive model can well capture dynamic response of IPCs.
An interpenetrating metal ceramic composite, based on a ceramic foam and an AlSi10Mg light-weight aluminum alloy, is investigated under compressive load. The ceramic preform is produced by mechanical ...stirring, drying and finally sintering. It has a relative density of approximately 25% and is infiltrated via gas-pressure infiltration with the aluminum alloy. The damage processes during compressive load, as well as an understanding of crack development is in focus of this research and obtained by complementing 2D and 3D characterization methods. Therefore, a 2D surface in-situ investigation setup with an universal testing machine, a digital image correlation and a microscopy setup is used. For 3D investigation, a compression test with an in-situ X-ray computed tomography is developed and carried out to get an understanding of the material crack growth and crack propagation, as well as its failure mechanisms inside the interpenetrating metal-ceramic phase composite. The material shows crack initiations in the ceramic phase parallel to the load direction. Formation of crack clusters is followed then by a change in failure mechanism due to shear stress dominated failure with a macroscopic crack in 45° regarding the load direction. A good-natured failure of the composite could be determined. The combination of the 2D and 3D investigation methods gives an insight into the failure behavior of the interpenetrating composite and thus contributes to the understanding of the failure mechanism beyond the current state of knowledge.
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