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Due to various difficult-to-machine materials and increasingly severe machining conditions, more and more attention has been paid to the physical vapor deposition (PVD) technology in recent decades to deposit hard coatings on cutting tools. Combined with the status of industrial application of PVD technology, this paper reviews the main PVD techniques for coated cutting tools from the perspective of the overall PVD coating equipment, including cathodic arc evaporation and magnetron sputtering as well as their hybrid techniques, and the plasma etching which is critical for coating adhesion strength is also involved. With regard to hard coating deposition on cutting tools, the basic principle, cathode configuration, magnetron and power supply are outlined. Issues related to target ionization ratio, coating deposition rate, coating properties and industrial application of numerous PVD techniques are also highlighted. On plasma etching, inert gas ion etching and metal ions etching are discussed. Finally, this paper summarizes and prospects the PVD technology used for coated cutting tools.

Physical vapor deposition (PVD) technology can modify the surface properties of equipment without changing the biomechanical properties of the substrate, and has been increasingly used in medical devices. Medical devices can be divided into surgical instruments, implantable medical devices and interventional medical devices according to the object and the way of application. For the defects of different medical devices during use, this paper reviews the development and application of PVD coatings to improve the performance and extend the life of medical devices. Finally, the development of PVD coatings for medical devices is expected.

This paper presents an extension of the basic truss layout optimization, in which the use of various materials is considered. A novel improved version of the particle swarm optimization algorithm, namely, GEMPSO, is developed for solving this problem. The enhancement is realized by introducing two core strategies: gradient estimation and multiple subpopulation division. The efficiency and reliability of the proposed improvements are demonstrated on a set of six test problems and three truss structures. Two multimaterial layout optimizations of truss structures are performed. The numerical results reveal that the appropriate partial use of expensive stronger materials can reduce the overall cost of multimaterial structures.

Reducing the sound pressure level (SPL) reliably and effectively is paramount in the presence of uncertainty. Herein, the robust optimisation of a vibro-acoustic system is performed by combining a probabilistic analysis approach and an approximate methodology. A surrogate model containing uncertain variables is established based on the elliptical basis function (EBF) neural network. Using Monte Carlo (MC) simulations, the probability distribution of the output responses are obtained, and the result shows that the sound pressure is influenced by uncertain factors. The simulated annealing (SA) algorithm is adopted to perform the robust optimisation. It shows that the optimisation results not only reduced the SPL inside the passenger car, but also enabled the SPL to be less sensitive to the fluctuations of the uncertain variables.