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This article reports the design, construction, and first use of an experimental device consisting of a specially designed vacuum chamber equipped with a reactive sputtering magnetron (RSM) to be used for controlled deposition of thin films on a Si(100) flat substrate. The setup was designed to allow for in situ and real-time recordings of X-ray diffraction patterns during the growth of the deposited films and was installed in the X-ray diffraction and spectroscopy beamline emerging from a superconducting wiggler source at the Brazilian Synchrotron Light Laboratory. The first use of the RSM setup was an in situ and real-time X-ray diffraction study of processes of growth of multilayered aluminum nitride thin films, whereas the operation parameters of the reactor were sequentially changed. This sequential process led to the development of multilayered films. Alternate variations in chamber pressure and magnetron power density allowed us to obtain thin films composed of several micrometer thick layers, with alternate amorphous and (10·0), (00·2), or (10·1) textured polycrystalline structures.

Atomic force microscope analysis of low load Vickers and Knoop indentation marks was performed to obtain a statistically consistent method for the mechanical characterisation of physical vapour deposition (PVD) coatings and the evaluation of elastic anisotropy. Indents shape analysis were elaborated with three different models for the evaluation of Young's modulus. Subsequently, roughness, elastic/plastic behaviour and intrinsic hardness have been numerically evaluated. Results showed that the intrinsic hardness evaluation of the films for applied loads as low as 50 mN is statistically supported by atomic force microscopy analysis of the indents, especially when diagonal length is smaller than 2/3 m. Moreover, some of magnetron sputtering PVDPlease confirm definition of MS. coatings showed mechanical anisotropy: normal to surface Young's modulus was higher than in plane Young's modulus. Such information would not have been obtained by nanoindentation testing alone and could be extremely important for the process development and production of high performance coatings for specific tribological applications

The present investigation has been carried out in order to study the erosion wear behaviour of WC–Co base thermal spray coatings. WC–12Co and WC–10Co–4Cr coatings were deposited by means of high velocity oxygen fuel (HVOF) thermal spraying. The erosion tests were conducted at impact angles of 30 and 90° using SiC particles of ~50 µm in diameter as erodent, at a velocity of 83·4 m s-1. It has been found that the erosion rate for both coated systems was higher when the test was carried out at an angle of 90°. The through-thickness residual stresses of the coatings, as well as the microstructural characterisation, allowed an explanation of the results and the erosion mechanisms in each case. It has been found that, under the experimental conditions carried out in the present study, the WC–10Co–4Cr coating exhibited a higher erosive wear resistance as compared to the WC–12Co coating.