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Laser cladding is used to coat and repair the surface of various components. A significant issue relating to optimisation of the process is the generation of residual stresses. These are affected by the high thermal gradients inherent in the process, and associated differential thermal contraction. These stresses can lead to various types of distortion. A customised 3‐D finite element model has been developed, incorporating these effects, based on simulation of conductive, convective and radiative heat transfer, and assuming elastic‐perfectly plastic deformation behaviour. Creep effects have been neglected and the cladding (particulate metal matrix composite) has been treated as a continuum. Comparisons are presented between measured and simulated thermal fields and specimen deflection histories. The results indicate that the main features of residual stress generation in this type of system have been captured in the model. Implications for process optimization and control are briefly discussed.

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In the present work, reactive magnetron sputtering in DC mode was used to grow complex oxide thin films, starting from two separate pure metal targets. A series of coatings was produced with a stoichiometry of the film ranging from MgO, over MgxAlyOz to Al2O3. The surface energy, crystallinity, hardness, refractive index, and surface roughness were investigated. A relationship between all properties studied and the Mg content of the samples was found. A critical compositional region for the Mg–Al–O system where all properties exhibit a change was noticed.

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Abstract. The effect of the target surface morphology on the sputter deposition flux and the energy flux is investigated by comparing solid targets to pressed powder targets. A significant, material dependent difference of the effective sputter yield between both target types is noticed. This difference is explained by combining two effects: a local increase of the elemental sputter yield and the redeposition of sputtered atoms onto the target. Both effects strongly depend on the target surface morphology. The experimental trends are reproduced by Monte Carlo simulations. This allows a description of the angular distribution of the sputtered atoms which is an important parameter to define the particle flux and the energy distribution of the atoms arriving on the substrate. Using the previously developed particle trajectory code simtra, the latter is demonstrated for the studied materials (Al, Ag, Cu, and Ti).