Metal matrix composite (MMC) materials have attracted tremendous interest since the early 2000s because of their superior physical, mechanical, thermal, and electrical properties compared to pure metals or alloys. The interest in developing MMCs can be explained by their unique features but especially by the fact that the properties can be tailored depending on the nature and concentration of the reinforcements. MMCs have found applications in a vast number of industries, such as aerospace, automotive, electronics which are the focus here.

The constant increase of power and packing densities in power electronic devices has led to heat dissipation issues. Significant demand for developing an efficient heat-dissipating material with a high thermal conductivity (TC) and a low coefficient of thermal expansion (CTE) has appeared in the past decades. To meet this demand, it is necessary to fabricate a material compatible with the electronic chip while ensuring the reliability of the power modules. Among the large number of MMCs, copper (Cu) and aluminum (Al) are the most advanced composites for thermal management applications (i.e., base plate, heat sink, and exchanger). Often carbon materials (C) such as carbon fibers, diamond, graphene or carbon nanotubes are added to the metal matrix because of their high TC and low CTE values. Cu/C and Al/C composites materials have already demonstrated their superior properties compare to current electronic packaging. Lower and tailorable CTE were observed depending on the volume fraction of reinforcement (e.g., CTE decreases when C concentration increases). High heat dissipation capability was shown, which surpass commercial heat exchangers. The addition of a lightweight reinforcement lowered the density of the material, making them attractive for aeronautics applications. Finally, high stiffness at elevated temperatures was tested and resulted in dimensional stability for high-temperature applications. Also, it is worth to note that the final properties of MMCs depend not only on the primary constituent of the materials but also on the fabrication methods.

In this paper, the Cu/C composites fabricated by powder metallurgy and hot uniaxial pressing are reviewed. Thermal analyses indicate that interfacial treatment is required to achieve high thermal and thermomechanical properties for all processing methods. An in-depth review of the interface control through novel surface treatments is presented such as interphase creation and unique processing methods. The review also focuses on the thermal transfer between the matrix and reinforcement. It is shown that proper control of the interfaces will form the right chemical/mechanical bonding, which enhances thermal and thermomechanical properties of the Cu/C composites.

• highlight the key advantages of AM in radiotherapy where rapid prototyping allows for patient-specific manufacture

• explore common clinical workflows involving radiotherapy tools such as bolus,compensators, anthropomorphic phantoms, immobilisers, and brachytherapy moulds; and

• investigate how current AM processes are exploited by researchers to achieve patient tissue-like imaging and dose attenuations.

Finally, significant AM research opportunities in this space are highlighted for their future advancements in radiotherapy for diagnostic and clinical research applications.

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This paper introduces the recent progress in methodologies and their related applications based on the soft x-ray interference lithography beamline in the Shanghai synchrotron radiation facility. Dual-beam, multibeam interference lithography and Talbot lithography have been adopted as basic methods in the beamline. To improve the experimental performance, a precisereal-time vibration evaluation system has been established; and the lithography stability has been greatly improved. In order to meet the demands for higher resolution and practical application, novel experimental methods have been developed, such as high-order diffraction interference exposure, high-aspect-ratio and large-area stitching exposure, and parallel direct writing achromatic Talbot lithography. As of now, a 25 nm half-pitch pattern has been obtained; and a cm² exposure area has been achieved in practical samples. The above methods have been applied to extreme ultraviolet photoresist evaluation, photonic crystal and surface plasmonic effect research, and so on.

Semiconductor and laser single crystals are usually brittle and hard, which need to be ground to have satisfactory surface integrity and dimensional precision prior to their applications. Improvement of the surface integrity of a ground crystal can shorten the time of a subsequent polishing process, thus reducing the manufacturing cost. The development of cost-effective grinding technologies for those crystals requires an in-depth understanding of their deformation and removal mechanisms. As a result, a great deal of research efforts were directed towards studying this topic in the past two or three decades. In this review, we aimed to summarize the deformation and removal characteristics of representative semiconductor and laser single crystals in accordance with the scale of mechanical loading, especially at extremely small scales. Their removal mechanisms were critically examined based on the evidence obtained from high-resolution TEM analyses. The relationships between machining conditions and removal behaviors were discussed to provide a guidance for further advancing of the grinding technologies for those crystals.

Total reflection x-ray fluorescence analysis is applied to trace element detection in liquid for effective environmental monitoring. This analytical approach requires x-ray total reflection mirrors. In order to achieve high sensitivity element detection, the mirrors require high surface quality for high x-ray reflectivity. Surface finishing for x-ray mirrors is typically conducted through a series of abrasive processes, such as grinding and polishing, and is thus time consuming. The purpose of this study is to streamline and enhance the surface finishing process based on unique high quality grinding techniques for the production of x-ray total reflection mirrors.