Ablation and mechanical properties of ZrC-reinforced PBI resin matrix composites

With the rapid development of laser technology, there is an increasing demand for laser protective materials. Thus, the mechanical and ablation properties of composite materials need to be further enhanced. Herein, solution impregnation and hot-press molding were used to develop composites containing various mass ratios of ZrC to polybenzimidazole (PBI) resin (thickness = 3 mm) for laser ablation applications. The results showed that adding short carbon fiber (SCF) to ZrC/PBI composites improves the ablation and mechanical properties. The ZrC/PBI/SCF composites were ablated using a high-energy continuous laser (7 kW cm⁻²), and the composites did not burn through. The composites did not peel off or split as the ablation process progressed. With the increase in the ZrC content in the composites, dense oxide layers are formed, enhancing the ablation properties of the composites. The ZrC/PBI/SCF composite (the ZrC/PBI mass ratio = 2:1) exhibited the lowest mass loss (2.24%), mass ablation rate (0.119 mg s⁻¹) and linear ablation rate (0.032 mm s⁻¹). This indicates that ZrC/PBI/SCF composites can be used as protective materials in high-energy continuous laser applications.     

Fiber Reinforced Polyimide Aerogel Composites with High Mechanical Strength for High Temperature Insulation

Glass fiber/polyimide aerogel composites are prepared by adding glass fiber mat to a polyimide sol derived from diamine, 4,4′‐oxydianiline, p‐phenylene diamine, and dianhydride, 3,3′,4,4′‐biphenyltetracarboxylic dianhydride. The fiber felt acts as a skeleton for support and shaping, reduces aerogel shrinkage during the preparation process, and improves the mechanical strength and thermal stability of the composite materials. These composites possess a mesoporous structure with densities as low as 0.143–0.177 g cm^?3, with the glass fiber functioning to improve the overall mechanical properties of the polyimide aerogel, which results in its Young's modulus increasing from 42.7 to 113.5 MPa. These composites are found to retain their structure after heating at 500 °C, in contrast to pure aerogels which decompose into shrunken ball‐like structures. These composites maintain their thermal stability in air and N₂ atmospheres, exhibiting a low thermal conductivity range of 0.023 to 0.029 W m^?1 K^?1 at room temperature and 0.057to 0.082 W m^?1 K^?1 at 500 °C. The high mechanical strengths, excellent thermal stabilities, and low thermal conductivities of these aerogel composites should ensure that they are potentially useful materials for insulation applications at high temperature.     

Dielectric response and electromagnetic wave absorption of novel macroporous short carbon fibers/mullite composites

For wider-band and stronger electromagnetic (EM) wave absorption, macroporous short carbon fibers/mullite matrix (C_f/Mu) composites were prepared via introducing short carbon fibers (0, 0.7, and 1.3 vol%) with length of 2-3 mm into macroporous mullite ceramic by gel-casting. The density of as-prepared C_f/Mu composites decreases from 2.93 g/cm³ to 2.74 g/cm³, while the porosity increases from 3.32% to 10.76% with the rise in carbon fibers content. The diameter of macropores in C_f/Mu composites is ranging from several microns to tens of microns. Complex permittivity and dielectric loss of the prepared composites in X-band (8.2-12.4 GHz) are significantly enhanced with increased carbon fibers content. The best EM wave absorption performance is obtained in the macroporous C_f/Mu composites containing only 0.7 vol% carbon fibers (C_f/Mu-0.7). The maximum absorption loss of C_f/Mu-0.7 is −38.3 dB at 12.08 GHz at the thickness of 2.1 mm, and effective absorption bandwidth below −10 dB (over 90% of EM wave absorption) covers the whole X band with the thickness of 2.35 mm. The results suggest that the C_f/Mu composites can be promising high-performance EM wave absorbing materials.     

Micro-Nanoarchitectonics of Electroless Cu/Ni Composite Materials Based on Wood

The changes of properties of wood-based Cu–Ni composites were studied via a simple electroless Cu and Ni method on wood surface to obtain Cu–Ni multilayer composites with excellent properties. The results showed that the wood was conducted via two times electroless Cu and one times electroless Ni had better performance, obtaining good surface roughness (9.99 μm) and good hydrophobic performance (contact angle, 122.5°). Here, Cu particles grew closely among Ni particles and embedded in Ni particles. The electrical conductivity of wood-based Cu–Ni composites was 2370.76 S/cm. When the electroless Ni was 55 min, the contact angle could reach 123°, indicating that the composite coatings had best hydrophobicity. The Ni/Cu, Cu/Cu, and Cu/Wood three layers with different electrical-magnetic properties can induce multiple reflections at each interface, which promote to the absorption attenuation. The average electromagnetic shielding effectiveness of Cu and Ni wood-based composites can reach 93.8 dB at L band ranging from 0.3?×?10^?3 to 3.0?×?10³ MHz with a low thickness (157 μm) and an ultralow density (0.75 g/cm³), verified the multilayer composite materials can block over 99.99% of incident EM waves.

     

Organic-inorganic composites for novel optical transformation induced by high-energy laser ablation

High-energy continuous-wave (CW) laser has been considered as a significant technology in recent decades. Such laser can destroy conventional materials in an extremely short time, necessitating their protection. In this study, zirconium carbide (ZrC) and silicon carbide (SiC) particle-modified short silicon carbide fiber-reinforced phenolic resin matrix composites (SiC/BPF-ZS) with significant anti-laser performance were designed and prepared. Our results showed that the ceramic particles and SiC fibers rapidly oxidized, leading to the formation of a ceramic coating composed of ZrO₂ and SiO₂. Owing to the formation of the ceramic coating, the reflectivity of the composites improved significantly from 15.8% to 73.2% after ablation at 500 W/cm² for 30 s. Additionally, the SiC fibers played an important role in the formation of a high-reflectivity coating during laser ablation. Contrast experiments indicated that SiC fibers lead to better performance than the carbon fibers. The high reflectivity and low mass ablation rate are demonstrated to be the key factors improving the anti-laser ablation performance of the SiC/BPF-ZS composites.     

New derivatives of indazole as electronically active materials

Synthesis and thermal, optical, electrochemical and photoelectrical properties of new indazole-based electroactive materials are reported. 1-Phenyl-5(6)-[N,N-(bisphenyl)]aminoindazoles and their methoxy-substituted analogues exhibit high thermal stabilities with the onset temperatures of thermal degradation ranging from 352 to 424 °C. The synthesized indazole derivatives form glasses with glass transition temperatures ranging from 35 to 39 °C. The synthesized compounds are electrochemically stable: their cyclic voltammograms show one reversible oxidation couple and no reduction waves. The ionization potentials of the solid samples of the synthesized materials are in the range of 5.3-5.9 eV. Methoxy-substituted derivatives show lower ionization potentials. Time-of-flight hole drift mobilities of 50% solid solution of 1-(4-methoxyphenyl)-5-{N,N-[bis(4-methoxyphenyl)]}aminoindazole in bisphenol Z polycarbonate reach 10⁻⁵ cm²/V s at high electric fields.     

Microstructure evolution and phase transformation of amorphous BCN–SiC composites prepared by two synthetic routes

Two amorphous BCN–SiC composites, sample BSC (BN + SiC + C) and sample BCSA (B₂O₃+C + Si + AlN) were prepared from different raw materials via spark plasma sintering (SPS) for 5 min at 1670 °C under a pressure of 30 MPa. Sample BCSA was found to generally outperform sample BSC, and its relative density (99.13% vs. 97.28%), flexural strength (453.1 MPa vs. 334.5 MPa), Vickers’ hardness (19.15 GPa vs. 16.53 GPa), and fracture toughness (5.21 MPa m^1/2 vs. 3.76 MPa m^1/2). The solid-phase reactions in the binary (sample BSC) and quaternary (sample BCSA) systems were elucidated from X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and thermodynamic calculations. The microstructure of the composites, which were synthesized from two different materials, was also characterized. The grain size and aspect ratio of the lamellar amorphous BCN grains played an important role in improving the mechanical properties of the composites. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) were used to clarify the microstructure of the amorphous phase of BCN and its interfacial area. Based on these results, element diffusion was discussed. The mechanism for the microstructural evolution and phase transformation of the composite were also discussed.     

Morphological,mechanical, and biological evolution of pure hydroxyapatite and its composites with titanium carbide for biomedical applications

Pure hydroxyapatite (HAp) was synthesized successfully via a wet chemical precipitation method. To study the influence of TiC (weight % of 5, 10, 15) substitution on the mechanical behavior of pure HAp, its composites with TiC were synthesized using a solid-state reaction method. Herein, detailed investigations of pure HAp and its composites using X-ray powder diffraction (XRD), FTIR spectroscopy, Raman spectroscopy, UV-VIS spectroscopy, SEM followed by EDAX and particle size analysis were carried out. XRD study reveals the phase stability of the prepared HAp and composite samples. However, FTIR and Raman spectroscopic studies revealed the bond formation among the various constituents. Mechanical behavior of HAp, and its composites with TiC were studied using numerous parameters like density, Young's modulus, fracture toughness, and load absorption capability. Based on these studies, it was revealed that the addition of 5 wt % substitution of TiC sintered at 1200 °C significantly enhanced the mechanical properties of pure HAp. Hence, 5 wt % of TiC composite 95HAp-5TiC showed the best mechanical characteristics such as density (2.3060 g/cm³), Young's modulus (14.53 MPa), fracture toughness (19.82 MPa m^1/2), maximum compressive strength (186 MPa) respectively. Cytotoxicity and osteogenic activities of the synthesized pure HAp and its composite, 95HAp-5TiC were performed using osteoblast cells (mouse calvarial) at different concentrations of the samples (0.01 μg, - 100 μg). From the above studies, the cell viability and ALP activities of the composite, 95HAp-5TiC found to be excellent than that of pure HAp. Hence, this composite sample may be utilized for bone implant applications.     

Stable and Color‐Tailorable White Light from Blue LEDs Using Color‐Converting Phosphor–Glass Composites

Commercial Ce³⁺:YAG phosphors were embedded in glass frits. Thermal condition for the viscous sintering of the composite materials was optimized. The phosphor–glass composites had maximum external efficiency of 30% and maximum light extraction efficiency of 39%. Color temperatures of the composites composed of fluorescent glass frits containing Eu³⁺ and Mn²⁺ combined with blue LEDs shifted from ~7000 to ~4000 K.     

ErBaCuO/PbO ceramic composites: Synthesis,physical properties,and radiation shielding performance

The search for shielding materials against ionizing radiation is very important due to the harmful effect that these radiations cause on human health and the environment. In this work, new ceramic composites of ErBa₂Cu₃O_x/lead oxide (ErBaCuO/PbO) instead of pure lead are proposed and prepared to serve as promising alternative materials for gamma radiation protection. X-ray diffraction was used to examine the structural properties of the prepared ceramic composites. The analysis showed that all composites have an orthorhombic structure with Pmmm symmetry. The addition of PbO induced distortion of the crystal structure of the ErBCO system. The structural parameters including lattice constants and unit cell volume showed a great variability with the addition of PbO. The physical properties including the density and porosity of the prepared ceramic composites were also determined. It was found that the density values increased from 4510 kg/m³ for 0 wt% to 4640, 4750, 4800 kg/m³ for 2, 5, and 10 wt%, respectively, while the porosity reduced with increasing the PbO content. The Monte Carlo simulation was used to estimate the linear attenuation coefficients of the as-prepared ceramics at different energies of gamma-ray photons ranging from 0.059 to 1.408 MeV. Other shielding parameters were computed, including half-value thickness, transmission factor, and radiation protection efficiency. The results showed an improvement in radiation protection efficiency and a decrease in the transmission factor values with increasing the concentration of PbO. For example, the half-value thickness reduced from 1.949 to 1.832 cm while the radiation protection efficiency increased from 29.93 to 31.51%, at gamma-ray energy of 0.662 MeV, once the concentration of PbO was increased from 0 to 10 wt %, respectively.     

Lightweight and thermally conductive thermoplastic polyurethane/hollow glass bead/boron nitride composites with flame retardancy

Polymeric composites with low density and high thermal conductivity (TC) are greatly demanded in some specific applications such as aeronautics, astronautics, and deep-sea exploration. It is a great challenge to obtain lightweight and thermally conductive polymer composites because the heat fillers have high density (>2 g/cm³) Herein, lightweight and thermally conductive thermoplastic polyurethane/hollow glass bead/boron nitride composites (TPU/HGB/BN) were prepared with the construction of a 3D BN network under the assistance of ultralightweight HGB by a solution-mixing and hot-pressing method. A 3D BN heat network has been constructed in the TPU matrix due to the alignment of the BN platelets along with the HGB microspheres during hot-pressing, which leads to a higher TC (5.34 W/mK) of the TPU/HGB/BN composites with a low density of 1.23 g/cm³, which is close to the density of pure TPU (1.20 g/cm³). In addition, the TPU/HGB/BN composites show good thermal stability with TC losses of 4.24% and 2.22%, respectively, even after treated for 50 hot-cold cycles and heated at 80 °C for 50 h. Moreover, the limiting oxygen index (LOI) of the TPU/HGB/BN composites is 51%, and they can extinguish in 8 s after ignition and exhibit enhanced flame retardancy. This work presents a simple method to design and prepare lightweight, flame retardant and thermally conductive composite materials, which can be used as lightweight thermal management materials.     

Electrically conductive porous alumina/graphite composite synthesized by starch consolidation with reductive sintering

This paper reports a facile and environment-friendly process to synthesize electrically conductive porous alumina/graphite composites by starch consolidation technique followed by reductive sintering. Green ceramic composites were consolidated with different starches and sintered at different temperatures in an argon atmosphere. Electrical measurements, carbon contents and Raman analyses of carbon structures determined an optimal sintering temperature of 1700 °C, which lead to a uniform formation of conductive graphitic networks at an optimal concentration of about 3.8 vol% in the porous composites. These carbon networks resulted into porous composites having high electrical conductivities measured in the range from 3 to 7 S/cm, which depended on the starch types and their porous properties. Correspondingly, the bulk porosities of the sintered composites were measured from 42 to 46%, with rounded micropores having diameters ranging from 14 to 39 μm. These porous properties of the sintered composites offer promising applications for conductive membrane and porous electrode.     

Influence of Surface Modified MWCNTs on the Mechanical, Electrical and Thermal Properties of Polyimide Nanocomposites

Polyamic acid, the precursor of polyimide, was used for the preparation of polyimide/multiwalled carbon nanotubes (MWCNTs) nanocomposite films by solvent casting technique. In order to enhance the chemical compatibility between polyimide matrix and MWCNTs, the latter was surface modified by incorporating acidic and amide groups by chemical treatment with nitric acid and octadecylamine (C₁₈H₃₉N), respectively. While the amide-MWCNT/polyimide composite shows higher mechanical properties at low loadings (<3 wt%), the acid-MWCNT/polyimide composites perform better at higher loadings (5 wt%). The tensile strength (TS) and the Young’s modulus (YM) values of the acid-MWCNT/polyimide composites at 5 wt% MWCNT loadings was 151 and 3360 MPa, respectively, an improvement of 54% in TS and 35% in YM over the neat polyimide film (TS = 98 MPa; YM = 2492 MPa). These MWCNT-reinforced composites show remarkable improvement in terms of thermal stability as compared to that for pure polyimide film. The electrical conductivity of 5 wt% acid modified MWCNTs/polyimide nanocomposites improved to 0.94 S cm ⁻¹ (6.67 × 10 ⁻¹⁸ S cm⁻¹ for pure polyimide) the maximum achieved so far for MWCNT-polyimide composites.     

Fabrication method,dielectric properties,and electromagnetic absorption performance of high alumina fly ash-based ceramic composites

Mullite-Al₂O₃-SiC composites were in-situ synthesized through carbothermal reduction reaction of fly ash (FA) with a high alumina content and activated carbon (AC). The effects of sintering temperature, holding time, and amount of AC on the β-SiC yield, microstructure, dielectric properties, and electromagnetic (EM) absorption performance of the composites in the 2–18 GHz frequency range were studied. The results show that increasing the AC improves the porosities of the composites, with the highest porosity of 56.17% observed. The β-SiC yield varies considerably as the sintering parameters were altered, with a maximum yield of 23% achieved under conditions of 12 wt% AC, 1400 °C sintering temperature, and 3 h holding time. With a thickness of 3.5 mm, this composite has excellent EM absorption performance, exhibiting a minimum reflection loss (RL_min) of -51.55 dB at 7.60 GHz. Significantly, the maximum effective absorption bandwidth (EAB) reaches 3.39 GHz when the thickness is 3.0 mm. These results demonstrate that the composite prepared under ideal conditions can absorb 99.99% of the waves passing through it. Because of the interfacial polarization, conductive loss, and impedance matching of the heterostructure, the synthesized mullite-Al₂O₃-SiC composites with densities ranging from 1.43 g/cm³ to 1.62 g/cm³ demonstrate outstanding EM attenuation capabilities. Therefore, this study presents a remarkable way of utilizing fly ash to fabricate inexpensive, functional ceramic materials for EM absorption applications.     

Dimensionality determined microwave absorption properties in ferrite/bio-carbon composites

Composition and structural design play a very influential role in the microwave absorption (MA) manipulation of ferrite/carbon composites. Here, by carefully choosing the dimensionality of the bio-carbon materials, the interfacial geometries and MA properties of ferrite/bio-carbon composites have been controlled effectively. The one dimensional (1D), two dimensional (2D), and three dimensional (3D) biomass-based carbon materials decorated with ZnFe₂O₄ (ZFO) particles were obtained respectively from carbon fibers (1D), tree leaves (2D), wheat straw (2D), peanut shell (3D) and orange peel (3D) by a simple two-step synthesis method. With increasing the bio-carbon's dimensionality from 1D, 2D to 3D, the ferrite/carbon composite's MA properties are promoted and the minimum reflection loss is enhanced from −9 dB to −45 dB. By changing the ZFO/3D-bio-carbon samples' thickness, a broad absorption range from 4 to 18 GHz can be covered. Moreover, the effective absorption bandwidth for ZFO/3D-bio-carbon can be modified up to 7.1 GHz, which covers the whole Ku band. These observations identified the important roles of the ferrite/carbon interface and dimensionality of carbon materials and provided an effective and low-cost route to design microwave absorption materials based on biomass-industrial waste composites.     

Preparation of biogum thickener and properties of recoverable fracturing fluid based on environmental protection

A recyclable biogum thickener was developed and employed as the main agent to compound a fracturing fluid system in order to address the issue of the problematic recovery of fracturing fluid system. By using infrared (IR), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), the physical characteristics and microstructure were examined. By using a rheometer, dynamic filtration loss, and an acid-etching fracture conductivity device, respectively, the system's temperature and shear resistance, dynamic filtration loss, and fracture conductivity damage were studied. The system's gum-breaking performance, formation water compatibility, and anti-expansion performance were then measured in accordance with standards. As a result of shearing at 170 s⁻¹ and 120°C for 2 h, the 4% biogum system's performance outperformed the other two systems in every way, according to the experimental findings. Its viscosity could also exceed 70 mPa · s. After breaking, the solution had a viscosity of 2.5 mPa · s, which was very compatible with the formation water. The system has a 90% anti-swelling rate, a filtration loss coefficient of 5.14 × 10⁻⁵, strong infiltration ability, and negligible formation damage. The biogum system's recovery rate after field application is discovered to be around 50%.     

In vitro evaluation and mechanical studies of MgO added borophosphate glasses for biomedical applications

The objective of current research is to evaluate the bioactive and tribological properties of the MgO doped borophosphate glass system. The glass system constituted of 40% B₂O₃ - (20-x) % CaO – 25% Li₂O – 15% P₂O₅ – x % MgO (mol%), x = 0, 0.5, 01, 02, 03 and synthesized using the melt quench technique. In-vitro bioactivity was determined using simulated body fluid (SBF) at 37 °C with time intervals of 7, 14 and 21 days. Hydroxyapatite (HA) layer formation was assessed using characterization techniques like XRD, FTIR and FESEM-EDS for structural, functional and morphological analysis respectively. The effect of MgO content on microhardness and tribological properties was studied by making cylindrical shaped glass samples. MTT assay was performed for various doses (62.5–1000 μg/ml) of glass dilutions using MG-63 cell line. In-vitro bioactivity showed higher Ca/P ratio with increase in MgO content after 21 days of immersion. MgO content seemed to promote degradation of glass due to formation of open structure in glass network. Borophosphate glass having 3% MgO exhibited the highest hardness value of 5.79(±0.08) GPa with minimum specific wear rate of 1.86 × 10^?11 and 1.38 × 10^?11 m³/Nm at a load of 15 N and 20 N respectively. MTT assay demonstrated the non-toxic behaviour of glass samples even at a higher dose level of 1000 μg/ml which confirmed its biocompatible behaviour. The study suggests that produced MgO doped borophosphate glass exhibits essential characteristics of bioactive materials and hence could be effective in bone filling and wound healing applications.     

Pyrolysis schedule optimization of benzoxazine-derived carbon/carbon composites through reaction rate optimization

Carbon-carbon composites (CCCs) are a form of carbon-fiber reinforced materials that exhibit excellent thermomechanical properties under extreme environmental conditions. To expand the applicability of CCCs, the fabrication process must be modified to reduce the cost or processing time. An optimization of this fabrication process was proposed for a thermoset benzoxazine-derived carbon-carbon composite and resulted in a 7 – hour pyrolytic schedule. This abbreviated schedule was achieved using a multi-stage nth – order kinetics model to limit individual reaction rates. These imposed limits reduced the internal pressures generated during thermal processing preventing layer separations and fiber rupture. The results of this modification were evaluated post heat treatment, via X-Ray 3D Computed Tomography, to ensure that the porous microstructure was fully interconnected with minimal closed void volume. Considering the absence of sample failure and closed void volumes of <1%, the pyrolysis schedule optimization was deemed successful in terms of producing a shortened cycle for a thermoset-derived CCC. To define the limitations of the optimization's applicability, a 1D model was proposed to predict the internal pressure generated during the final ramp as a function of decomposition kinetics, the through-thickness length, and the air permeability. Analysis of these predicted pressures resulted in a design chart that provided the upper bounds of the optimization protocol as it relates to sample thicknesses ≤50 mm and applied ramp rates ≤40 °C min⁻¹.     

MgFe1.98O4 – BaFe12O19 magneto-dielectric composites based ferrite resonator antenna for super-high frequency applications

The structural, morphological, and wideband electromagnetic response of (1-x) MgFe_1.98O₄ + x BaFe₁₂O₁₉ composites with x = 20, 40, 60, and 80 wt percent (wt%) were investigated. The composites' sintering temperature was optimised to be 1250 °C for 2 h. The phase purity and independent existence of the end members in the composites were verified using XRD, Raman and FTIR spectroscopy. The microstructures of the sintered composites indicate the effect of grain growth on the density and grain packing efficiency. The relative permittivity of the composites is in the 9–11 range, while the relative permeability is between 1.4 and 2.8. The increase in BaFe₁₂O₁₉ concentration from 20 to 80 wt% resulted in a dilution effect in permeability and enhanced saturation magnetization and coercive field strength. The composites with 20–80 wt% BaFe₁₂O₁₉ possess a characteristic impedance ranging from 0.55 to 0.38 and a miniaturisation factor ranging from 5.16 to 3.82 at 900 MHz. The composites containing 20 and 40 wt% BaFe₁₂O₁₉ exhibited appreciable miniaturisation factors of 5.16 and 5.24, respectively, with characteristic impedances of 0.55 and 0.47. Furthermore, these composites have low magnetic and dielectric losses of the order of 10^?1 and 10^?3, respectively, making them suitable candidates for resonator antenna applications. A magneto-dielectric resonator antenna using the composite comprising 40 wt% BaFe₁₂O₁₉, with a density greater than 95%, was designed, simulated and fabricated. The fabricated magneto-dielectric resonator antenna resonated at a frequency of 14.7 GHz, with a significantly low return loss of ?44 dB and wide impedance bandwidth of 1.44 GHz, suggesting the application potential of the dual-ferrite composite in the Ku-band frequency range.     

Elastic behaviour of zirconium titanate-zirconia bulk composite materials at room and high temperature

Zirconium titanate-zirconia composites have potential for applications involving variations of temperature. Elastic characterization is necessary to evaluate stresses developed in materials which may be used in these kinds of applications. In this work, Young's and shear modulus and Poisson's ratio of two zirconium titanate-zirconia bulk composites (Z(Y)T70 and Z(Y)T50) have been determined at room temperature by the Impulse Excitation Technique (IET). Furthermore, Young's modulus (E) has been determined at high temperature (up to 1400 °C) for both composites. Young's modulus of Z(Y)T70 composite decreases ≈6% between room temperature and 400 °C due to the presence of zirconia. From 400 to 1400 °C, the decrease of E (≈14%) is due to the presence of zirconium titanate. Young's modulus behaviour at high temperature of Z(Y)T50 composite is determined by the degree of microcrack healing, which depends on the maximum temperature reached.