In this research, the mechanical properties of recycled aluminum (A356-A7075)-based composites reinforced with Nb2Al-ZrO2-TiAl have been evaluated. Different amounts of Nb2Al doped with ZrO2 were mixed with atomized recycled aluminum matrix containing “AA356-A7075” and processed by ball milling. The mixture was then sintered followed by hot forging. Static and cyclic stress relaxation compression tests and low velocity impact tests were carried out to evaluate damage behavior. Interface and microstructure of these composites were also evaluated by scanning electron microscope (SEM).

In this chapter, the microstructural formation and static/cyclic compression behavior of recycled Alumix (aluminum alloy) matrix hybrid composites reinforced with TiB2, TiC, and B4C are studied. It is aimed as an alternative to traditional alloys/composites used in the aeronautical industry. These composites are generally produced by using a combined sintering + forging process. The static and dynamic properties are evaluated in detail, taking into account the relevant scanning electron microscopy microstructures (including the distribution of reinforced elements).

A new recycled hybrid composite has been designed by using a special doping process and a combined method, “sintering + forging” of recycled “AA 7075 + AA1050” and basically used rice husk as a fine powder and graphene nanoplatelets. Static and cyclic behaviours of these composites and also time-dependent behaviour called modified fatigue behaviours have been evaluated under compression solicitation. A detailed damage analysis has been performed using scanning electron microscopy.

In this study, the microstructural formation and static/cyclic compression behavior of “Ni-Al+AA7075+AA1050”-based composites reinforced with ceramics (TiC-TiB2) have been evaluated. It is aimed at creating a new design to be an alternative to traditional alloys/composites used in the aeronautical industry. These composites are generally produced using a combined method that we call “sinter + forging processes”. The static and dynamic properties and also the microstructure (including the distribution of reinforcement elements) are evaluated in detail.

Within the framework of the common research project, the mechanical properties and fatigue behaviour of recycled thin sheet Ti-Al-based composites reinforced with atomized scrap aluminium (AA7075) and Nb elements have been evaluated. All the thin sheet sandwich structures were produced by the hot forging process, which is a semi-solid-forming process similar to partial melting hot forging. The effect of the chemical bonds during the production of these multifunctional sandwich composite structures was analysed using 3-point bending tests under static and dynamic (fatigue) loading conditions. Additional tensile tests have been carried out to evaluate the mating effect. Interface and microstructure of these composites have also been evaluated using scanning electron microscopy.

In the frame of the common research project, the mechanical properties of recycled gas atomized scrap aluminium (AA 7075)-based composites reinforced with nano filler NiAl intermetallic and niobium (Nb) elements have been evaluated. Firstly, the mixture was homogenized by means of a ball milling process for 4 hours. After cold compaction of the compositions, the final specimens have been produced with "vacuum arc melting" for aeronautical applications. Static and dynamic compression tests have been conducted. Additional tensile tests have also been carried out. Experimental results were compared with a finite element method. The interface and microstructure of these composites have also been evaluated by a scanning electron microscopy.

In the frame of the research project that is going on, the mechanical properties of recycled gas atomized scrap aluminium (AA7075) based hybrid composites reinforced with nano SiC filler (whisker)+ Graphene Nano plateless (GNP) and fine carbon Fibers elements have been evaluated. Firstly, the mixture was homogenized by means of ball milling process during 4 hours. After hot compaction at 200°C compaction of the compositions the final specimens have been produced with the novel combined method called "SINTER+FORGING" at 650°C followed by relaxation treatment at 200°C during the 2 hours. This type of hybrid composite is used for aeronautical applications. Static and dynamic-Time dependent compression tests have been conducted. Interface and microstructure of these composites have also been evaluated by Scanning Electron Microscope (SEM).

Conductive biohybrid cell-material systems have applications in bioelectronics and biorobotics. To date, conductive scaffolds are limited to those with low electrical conductivity or 2D sheets. Here, 3D biohybrid conductive systems are developed using fibroblasts or cardiomyocytes integrated with carbon nanotube (CNT) forests that are densified due to interactions with a gelatin coating. CNT forest scaffolds with a height range of 120–240 µm and an average electrical conductivity of 0.6 S/cm are developed and shown to be cytocompatible as evidenced from greater than 89% viability measured by live-dead assay on both cells on day 1. The cells spread on top and along the height of the CNT forest scaffolds. Finally, the scaffolds have no adverse effects on the expression of genes related to cardiomyocyte maturation and functionality, or fibroblast migration, adhesion, and spreading. The results show that the scaffold could be used in applications ranging from organ-on-a-chip systems to muscle actuators. Graphical abstract

In the frame of the common research project, manufacturing of thin sheet Ni-Ti based composites reinforced with Nb and TiB2 have been carried out through hot-forged bonding process for a high strength sandwich structure for the aeronautical engineering applications. Interface and bonding characteristics of hot forged composites have been evaluated heat treated at 550–600 °C depending on the operational parameters under laboratory conditions. Formability behaviour and delamination phenomenon have also been analysed by 3P Bending tests. An intermetallic phase layer has been carried out between the titanium and nickel sheet layers containing of hard particles reinforcements between the sheets by using hot forging process. Finally a high strength bonding has been carried out by mechanical joining and very strong chemical bonding diffusion during this process depending on the temperature and the time. With the finite element model developed with reference to these tests, the mechanical behaviour of the material is supported by simulations made with the Abaqus software. Finally, more detailed mechanical/physical properties of this developed material were investigated by applying wear and creep tests. Certain area in the microstructure have been analysed with SEM.

In this study, a novel recycled Al 431 + 1050 based composites reinforced with “TiC” were designed for aeronautical applications with high resistant structure against to choc and static loading under service conditions. Static/dynamic compression behaviours of these composites were evaluated. Basically, laboratory-scale test samples were produced using combined “sinter + forging” production methods. Al 431 + 1050, a mixture of recycled and modified aluminium alloys, was used as the main matrix material. Different proportions of TiC (10, 15 and 20 wt %) were used as a major reinforcement element. As minor reinforcements, Mo and Cu metal powders and a small amount of Graphene Nano Platelets, (GNPs), and Alumina, (γ-Al2O3) fibre were used to compare their influence on the mechanical properties of these hybrid composite structures.

In this project, design of niobium-aluminium (Nb2Al) intermetallics based composites is proposed by using the fresh scrap recycled niobium and aluminium alloy AA7075. These compositions will be the target for aeronautical engineering applications for high temperature service conditions. Manufacturing of these composites is an important engineering case for tailored behaviour of the composites produced through combined method of powder metallurgy route; sintering followed by forging. Different materials and operational (process) parameters will be used for optimization of the compositions. All of the analyses will be devoted to the static (compression, 3-point bending) test conditions. Microstructure analyses (matrix/interface) will be carried out by Scanning Electron Microscope (SEM). At this stage of the project, the primary objective would be to establish a continuum-based material model in order to capture the macroscopic behaviour of the targeted composite materials and numerically reproduce the results from the basic characterization tests (3P bending). The model will be implemented for Finite Element Analysis Software ABAQUS/Explicit as a user subroutine VUMAT for explicit nonlinear finite element calculations. The second step would be modelling of the microstructure of the proposed hybrid Nb2Al based composites and simulate the behaviour of several RVEs and see the effect of the sintered-forging and different ratios of reinforcing particulates.

In this study, the microstructural formation and static/dynamic compression behaviour of recycled AA7075 based hybrid composites reinforced with ZrO2and Al2O3 fibres were investigated. The effects of the hybrid metal matrix composites on the mechanical behaviour (quasi-static compression, dynamic compression, three-point bending and microhardness) have been investigated in detail by using ZrO2 as a reinforcement element in two different proportions. It is aimed to be an alternative to traditional alloys used in the aeronautic industry. These composites were produced using by combined sinter + forging processes. The static and dynamic properties have been evaluated in detail, taking into account the relevant Scanning Electron Microscopy (SEM) microstructures (including the distribution of reinforcement elements).

In this study, the microstructural formation and static/dynamic compression behaviour of the recycled Ti-Al-Cu matrix hybrid composites reinforced with silicon whiskers and alumina (Al2O3) fibres are examined. It is intended to be an alternative to traditional alloys/composites used in the aeronautical industry. These composites are generally produced using combined sintering + forging processes. The static and dynamic properties are evaluated in detail, taking into account the relevant scanning electron microscopy (SEM) microstructures, including the distribution of reinforcement elements.

In this study, the microstructural formation and static/dynamic compression behaviour of the recycled Ni-Al/Nb2Al/ZrO2 matrix-hybrid composites reinforced with Nb and ZrO2 will be studied. It is intended to be an alternative to traditional alloys/composites used in the aeronautical industry. These composites are generally produced by using combined sintering + forging processes. The static and dynamic properties will be evaluated in detail, considering the relevant scanning electron microscopy (SEM) microstructures, including the distribution of reinforcement elements.

The present work, reviews the toughening mechanisms and microstructural analyses of recycled aluminium matrix composites reinforced with γ-alumina and pure recycled copper. This composite was manufactured by sintering and sinter + forging called the combined process. Static compression, 3-point bending, impact (drop-weight) tests were conducted to evaluate mechanical response of the composites. Additionally, wear and creep tests were carried out with a nanoindenter to evaluate wear and time dependent behaviour of this composite. Detailed analyses of microstructure of the composites was performed with Scanning Electron Microscopy (SEM) supported by EDS analyses. The results showed that, the composites have homogeneous structure without porosity and very homogeneous distribution of fine γ-alumina (Al2O3) and copper particles. Sinter + forging process yielded a material that had higher strength, hardness and better resistance to wear. This composite will be targeted for linkage applications where high toughness and high surface damage resistance is required.

The present work, reviews the mechanical and microstructural analyses, of copper and silicon carbide reinforced recycled aluminium matrix (Alumix 431) composites manufactured by sinter+forging technique. Static compression, impact tests and also scratch damage tests were carried out. Detail analyses of Scanning Electron Microscopy (SEM) supported by XRD, thermal and electrical conductivity measurements have been carried out on the specimens before and after the tests.

Abstract Hybrid intermetallic composites (HICs-aluminum based matrix, new hybrid design) reinforced with titanium nitride (TiN) and alumina (γ-Al2O3) were designed and manufactured through the innovative combined method of sinter + forging. This method results in highly dense materials with, in general, improved mechanical properties. In the composites TiN content was varied (10, 20 and 30 wt %) but γ-Al2O3 content was kept constant at 10 wt%. Additionally, 5 wt% each of Cu and Ni were mixed in to improve processing of the composites. The mechanical properties were specified by different destructive test methods (wear performance, micro hardness, quasi-static compression, three-point bending tests). Wear performance was investigated by scratch experiments. Scanning electron microscopy (SEM) was used to determine the microstructure, interface characteristics and the fracture surfaces. The SEM analysis yielded that TiN powders were located at the grain boundaries and this can be attributed to the improvement observed in the mechanical properties and wear performance with the addition of TiN.

In the frame of the common research project, the mechanical behaviour of recycled thin sheet Ti-Al based composites reinforced with scrap pure aluminium (AA1050) and boron, B reinforcement elements have been used with thin Ti-Al sheet recycled by hot forging method. The effects of chemical bonds during the production of these multifunctional sandwich composite structures were analyzed by 3-point bending tests to evaluated hyper elasticity behaviour. The same idea has been carried out this time on the Ti-Al based composites performed by sintered + forging through the powder metallurgy route by using different reinforcements such as TiB2, TiC, and B4C. Quasi static compression and low velocity impact (drop weight) tests have been performed on the sintered + forging specimens with a drop tower to observe the response of theses composites under the dynamic loading conditions. Interface and microstructure of these composites have been evaluated by Scanning Electron Microscope (SEM).

Huntsman–Merrimack MIRALON® carbon nanotubes (CNTs) are a novel, highly entangled, commercially available, and scalable format of nanotubes. As-received and acid-treated CNTs were added to aerospace grade epoxy (CYCOM® 977-3), and the composites were characterized. The epoxy resin is expected to infiltrate the network of the CNTs and could improve mechanical properties. Epoxy composites were tested for flexural and viscoelastic properties and the as-received and acid treated CNTs were characterized using Field-Emission Scanning and Transmission Electron Microscopy, X-Ray Photoelectron Spectroscopy, and Thermogravimetric Analysis. Composites containing 0.4 wt% as-received CNTs showed an increase in flexural strength, from 136.9 MPa for neat epoxy to 147.5 MPa. In addition, the flexural modulus increased from 3.88 GPa for the neat epoxy to 4.24 GPa and 4.49 GPa for the 2.0 wt% and 3.0 wt% as-received CNT/epoxy composites, respectively. FE-SEM micrographs indicated good dispersion of the CNTs in the as-received CNT/epoxy composites and the 10 M nitric acid 6 h treatment at 120 °C CNT/epoxy composites. CNTs treated with 10 M nitric acid for 6 h at 120 °C added oxygen containing functional groups (C–O, C=O, and O=C–O) and removed iron catalyst present on the as-received CNTs, but the flexural properties were not improved compared to the as-received CNT/epoxy composites.

Aluminium Metal Matrix Composites (AMMCs) have very light weight, high strength, and show better resistance to corrosion, oxidation, and wear. Impact resistance is an especially important property of these AMMCs which is essential for automotive applications. In this study, recycled aluminium matrix composites were designed through the powder metallurgy route. As matrix, fresh scrap aluminium chips (Alumix-123), by-product of machining coming from the French aeronautical company, were used. Fine -alumina particles (γ-Al2O3, 10 wt %), were used as main reinforcement element for the present work. As secondary reinforcements, Mo and Cu were added in the matrix. In this study, a typical low cost but high performance metal matrix composite was designed by using recycled aluminum chips (Alumix-123). This process comprises of the mixing, blending and compacting of aluminum chips through press moulding and pre-sintering and finally forging. In the final stage, material parameters were optimized for improving physical and mechanical properties of these composites. Further, the influence of reinforcement’s type and content on the mechanical properties has also been reviewed and discussed. Damping capacities and damage were analysed by drop weight and quasi static compression tests. Microstructures were analysed by the Scanning Electron Microscope (SEM).