Chapter Fabrication Methodologies of Biomimetic and Bioactive Scaffolds for Tissue Engineering Applications

Tissue engineering has offered wide technologies for developing functional biomaterials substitutes for repair and regeneration of damaged tissue and organs. Biomimetic materials with their inherent nature to mimic natural materials are possible through the recent advances in the fabrication technology. With the help of porous or dense implants made with biodegradable materials, it is possible to incorporate different vital growth factors, genes, drugs, stem cells and proteins. In this review, we presented various fabrication methodologies of biomimetic and bioactive scaffolds for tissue engineering applications. An overview of the nanocomposites of biomaterials is presented. Further an example of one of the hybrid nanocomposite material is given for additive manufacturing

Nanostructured Pure and Doped Zirconia: Synthesis and Sintering for SOFC and Optical Applications

Zirconia is a multifunctional material with potential applications in wide domains. Rare-earth doped zirconia and stabilized zirconia yield interesting properties based on the phase transitions induced by the sintering conditions. Zirconia nanopowders were prepared by hydrothermal technique. Synthesis methods of zirconia with various rare earths are discussed here. An overview of the sintering of zirconia-based ceramics is presented in particular for SOFC and sensors and optical applications

Isotropic thermal expansion in anisotropic thermal management composites filled with carbon fibres and graphite

Light materials with high thermal conductivity and low thermal expansion have a wide application potential for the thermal management of high-performance electronics, in particular in mobile and aerospace applications. We present here metal matrix composites with a mixture of graphite flakes and pitch-based carbon fibres as filler. The production by spark plasma sintering orients the filler particles on to a plane perpendicular to the pressing axis. The obtained materials have lower density than aluminium combined with a thermal conductivity significantly outperforming the used metal matrix. Depending on the ratio of the filler components, a low thermal expansion along the pressing direction (high graphite flakes content) or across the pressing direction (high carbon fibre content) is achieved. For a 1:3 ratio of carbon fibres to graphite, we measured an isotropic reduction of the thermal expansion of the matrix by up to 55%. We present a detailed characterisation of composites with two aluminium alloys as matrix and an overview of the properties for six different metal matrices including magnesium and copper. With the goal of a technical application, we show that the described properties are intrinsic to the material compositions and are achieved with a wide spectrum of production methods

The methodologies and strategies for the development of novel material systems and coatings for applications in extreme environments - a critical review

The aim of this paper is to present a critical analysis of existing methodologies, approaches and strategies used to develop materials systems and coatings for uses in extreme environments. The extreme or harsh conditions encompass a large variety of in-service forms such as: extreme temperatures, abrasion, corrosion, impact and radiation that can exist in various applications such as those associated with aerospace and aeronautical engineering, land and marine transport, manufacturing machinery, and even microelectronics products. This article describes how working environment and required service performance of a particular part or structure could affect the choice of materials and surfaces to which it is composed. In addition, the paper explains the relevance that abusive working environments have for industry, especially relating to their costs, being followed by an overview of surface deposition approaches that are currently popularly used to improve performance of mechanical devices that need to combat adverse conditions. Finally, a material system and three kinds of protective coatings that could be used in applications in extreme conditions are described. The critical review is an outcome of the strategic review from the EU H2020 SUPERMAT project which deals with materials and manufacture for the products/structural parts used in extreme conditions

Dense MgB2 Ceramics by Ultrahigh Pressure Field-Assisted Sintering

Magnesium diboride (MgB2) ceramics, due to their impressive transition temperature of 39 K for superconductivity, have been widely investigated. The possibility to obtain highly dense MgB2 ceramics with fine microstructure and grain boundaries acting as pinning sites by novel high-pressure-assisted spark plasma sintering (HP-SPS) is reported in this article. HP-SPS was employed to reach 100% density in MgB2 ceramics, and high pressure was utilized in the consolidation of MgB2. An increase in pressure helped in stabilizing the MgB2 phase above thermal decomposition, thus avoiding the formation of non-superconducting phases such as MgO and MgB4. Pressure allowed strengthening of the covalent bond (condensation effect) to increase the thermal stability of MgB2. HP-SPS yielded high mechanical hardness in MgB2 (1488 HV). For better electrical connectivity, which leads to large magnetic moments in high density samples were obtained with the beneficial effect of high applied pressure (1.7–5 GPa) at high temperature (>1000 °C). The combination of the SPS process and high pressure ensured retention of the homogeneous fine microstructure required to obtain high current density and high hardness

Thermoelectric and magneto-optic semiconductor single crystals and ceramics

International audienceSemiconductor materials have applications in vast fields and are the basis for modern electronics. Semiconductors materials have electrical conductivity intermediate between that of metal and insulators. In this chapter we will discuss about the applications of semiconductors in thermoelectric devices and magneto-optics..

Terbium based crystals and transparent ceramics phosphors- fabrication and applications

The recent upsurge of investigations on luminescent properties of inorganic phosphors is due to the applications in flat panel displays and various other luminescent devices..

Terbium based crystals and transparent ceramics phosphors- fabrication and applications

The recent upsurge of investigations on luminescent properties of inorganic phosphors is due to the applications in flat panel displays and various other luminescent devices..

Hydrothermal crystal growth from SiO2-GeO2 solid solution for piezoelectric applications

Hydrothermal crystal growth offers a complementary alternative to many of the classical techniques of crystal growth used to synthesize new materials and grow bulk crystals for specific applications..