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In this review, the EMI shielding properties of the various carbonaceous fillers are thoroughly reviewed. Electromagnetic interference (EMI) had been a cause of major concern in the live broadcasting, entertainment, aviation and defense industries since vital radio signals could create more interference, which could lead to poor performance. To reduce the effect of EMI, the organic polymeric composites along with the carbonaceous fillers are mostly used since they are flexible, low denser, high mechanical strength, high thermo‐stability, high electrical and thermal conductivity, excellent fracture toughness, and high friction/wear resistance. There are lot of carbon based materials are being used as EMI shielding material in mono and compound form. This review gives a broad understanding of the utilization of carbonaceous fillers in polymer matrixes. Thus, the overall coverage on this carbon based materials and their effectiveness could help the researchers to find right carbon material for suitable application. According to this review, the absorption mechanism is vital to achieve high EMI shielding effect. The fillers such as graphene and CNTs are most preferable EMI shielding filler, according to the vast coverage of previous articles. However, there are more magnetoelectric materials also evolved recently, having combined properties of both conductive and magnetic, yielding high SE at elevated frequencies. [ABSTRACT FROM AUTHOR]

Owing to its good tribological and mechanical properties, polyamide material was widely applied to prepare sliding mechanical parts. A lot of studies confirmed that adding different functional materials or surface modifications to polyamide could reduce the friction coefficient, improve wear resistance and reduce water absorption, so as to prolong the service life of polyamide parts. This paper summarized the common reinforcement methods of polyamide materials: blending, surface modification and filler. The reinforcing mechanism of different fillers and polymers, the effects of different methods on the tribological properties, mechanical properties and water absorption of polyamide composites, and the preparation methods of polyamide composites have been systematically discussed. [ABSTRACT FROM AUTHOR]

Cryogenic treatment is a thermal treatment process in which the parts are usually cooled to temperatures below −70 C (< 203 K) to induce metallurgical changes in materials. The treatment has shown a significant performance improvement in most of the ferrous materials and it's alloy, by transforming retained austenite to martensite and precipitating secondary carbides. However, the effect of such low-temperature treatment on highly stable super hard material like tungsten carbide (commonly referred to as "cemented carbide") is uncertain. But researchers have reported precipitation of eta-phase carbides, densification of cobalt binder, refinement of tungsten carbide grains, phase transformation of cobalt, and changes in residual stress in cryogenically treated tungsten carbide (WC-Co) material which resulted in increased hardness and wear resistance. Hence, this paper focuses on summarizing the cryogenic treatment parameters used in different studies, the rate of performance improvement in different applications, and reported mechanical and metallurgical changes, which would serve as a pool of knowledge for future researchers. [ABSTRACT FROM AUTHOR]

Low toughness and wear resistance have limited application of many bioceramics in biomedical applications requiring load bearing capability. Spark plasma sintering (SPS) has widened the envelope of processing conditions available to produce bioceramics with new microstructural architectures. SPS has enabled realisation of transparent hydroxyapatite (HA) by providing the means to consolidate fully dense nanostructured HA. Recently, low-dimensional carbon nanomaterials, including carbon nanotubes (CNTs) and graphene/graphene nanoplatelets (GNP) have gained increasing attention as reinforcements due to their providing superior mechanical properties, favourable biocompatibility, and large specific surface area. Processing of these nanocomposites is done using SPS in order to consolidate the ceramics to full density in short time periods, while retaining the structure and properties of the nanomaterial reinforcements. This review focuses on recent progress on GNP/CNT reinforced HA and alumina nanocomposites, including mechanical properties, tribological behaviour, processing conditions, and mechanisms. Biocompatibility of these promising bioceramics with various cells/tissues are discussed. [ABSTRACT FROM AUTHOR]