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Purpose Materials with a high thermal conductivity, such as Cu-alloys hold the most interest to the plastic moulding industry. Additive manufacturing (AM), especially selective laser melting (SLM) of metals, allows the production of parts with complicated internal cooling and increased production efficiency. The portfolio of alloys for metal AM is limited and still missing process parameters for the processing of copper alloys. This paper aims to preview the process parameters of high-strength alloy Cu7.2Ni1.8Si1Cr processed by SLM. Design/methodology/approach An experimental approach is adopted to investigate porosity and mechanical properties of SLM specimens and its comparison with standard material AMPCOLOY 944. Optimization of porosity was performed using line and cube specimens; mechanical properties and microstructure were evaluated by tensile testing and metallography. Findings Optimum processing parameters for fabrication of Cu-alloy specimens with a relative density of 99.95 per cent were identified, and no cracks were detected. Mechanical testing of SLM specimens showed the ultimate tensile strength, proof stress of 0.2 and elongation of 380, 545 MPa and 16.9 per cent. The alloy is suitable for laser AM, thanks to its processability at a relatively high laser scanning speeds and thus its promising price of part/costs ratio. Research limitations/implications The paper describes the initial state of research – the follow-up tests focussed on mechanical testing, fatigue and statistical evaluation need to be conducted. The process parameters are developed only for bulk geometry – optimal setup for lattice structures and thin walls has not been explored yet. Practical implications The research findings in this work could be used for production of 3D printed parts and after the tuning of additional parameters, e.g. for up- and down-skin zones, could be used for special application such as energy exchange. Originality/value This work produces the processing of new material suitable for laser AM. Cu7.2Ni1.8Si1Cr alloy could be the prospective material from the group of Cu alloys suitable for moulds manufacturing and thermal applications.

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Magnesium, as a biodegradable metal, offers great potential for use as a temporary implant material, which dissolves in the course of bone tissue healing. It can sufficiently support the bone and promote the bone healing process. However, the corrosion resistance of magnesium implants must be enhanced before its application in clinical practice. A promising approach of enhancing the corrosion resistance is deposition of bioactive coating, which can reduce the corrosion rate of the implants and promote bone healing. Therefore, a well-designed substrate-coating system allowing a good control of the degradation behavior is highly desirable for tailored implants for specific groups of patients with particular needs. In this contribution, the influence of coating formation conditions on the characteristics of potentiostatically electrodeposited CaP coatings on magnesium substrate was evaluated. Results showed that potential variation led to formation of coatings with the same chemical composition, but very different morphologies.Parameters that mostly influence the coating performance, such as the thickness, uniformity, deposits size, and orientation, varied from produced coating to coating. These characteristics of CaP coatings on magnesium were controlled by coating formation potential, and it was demonstrated that the electrodeposition could be a promising coating technique for production of tailored magnesium-CaP implants.

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The diffusion couples for experimental study were prepared by HVOF spraying of nickel and nickel with 20 wt.% of chromium powders onto an aluminium sheet surface. The interfaces with sharp gradients of chemical concentration of these elements were prepared. Annealing at temperatures of 600°C and 630°C, close to the Al + Al3Ni eutectic melting point (639.9°C), with different dwell times were used. During annealing, the reactants diffuse and form layers of Al3Ni2 and Al3Ni intermediate phase compositions. Moreover, nickel without the assistance of chromium diffuses preferably along the grain boundaries into aluminium substrate and produces the strengthening of the substrate by stable Al3Ni and metastable Al9Ni2 particles. The microstructures were obtained by scanning electron microscopy. Layer thickness measurements were realized by means of image analyses. Chemical composition was estimated by energy dispersive microanalysis measurements. According to the results of the analyses performed the average chemical interdiffusion coefficients and Wagner’s integral interdiffusion coefficients were calculated.