Structure and properties of porous nickel and copper films produced by vacuum deposition from the vapour phase

The porous thick nickel and copper films were deposited by electron beam physical vapour deposition (EB-PVD) in vacuum. The microstructure and deformation behaviour of the films were investigated using scanning electron microscopy and high temperature dilatometer. It is shown that porous structure of vacuum condensates is unstable, and at heating it transforms from open-type porous structure into porous structure of closed type. It is assumed that such thermal instability of porous structure can be due to the presence of high density of vacancy-type defects in the structure of such materials. Change of structural state of vacuum condensates during heating at application of continuous load influences the conditions of their superplastic deformation. Possibility of application of such foils as interlayers in pressure welding is discussed.