Papers by Author: S.J. Skrzypek

Abstract: Influence of the electrodepositing parameters e.g. applied electric current as variable on texture formation and on mechanical properties of copper thin films was studied. Experiment was done for copper deposition from sulphate bath under galvanostatic and pulse current. It was found that copper layers exhibits different texture depending on applied current conditions during electrodepositing process. Pulse and direct current conditions leads to different texture of electrodeposited copper. Texture of electrodeposited copper coatings and mechanical properties could be correlated. It was found that, texture indexes although are not complex information about texture could be used for analysis of such correlation in technological process.

Abstract: Electrodeposition and other methods are employed to obtain metallic films and coatings. Copper coatings are most extensively used in circuit board industry and often as a base to further formation of other metallic films. Electrodeposited copper films (thin layers) are widely used in electronic and automotive industry so its electrical and mechanical properties and its thickness are important. Several methods are used for thickness determination of thin films and coatings for example mechanical, magnetic and ball crater with light microscopy methods. They are destructive and not precise enough. The X-ray fluorescence, absorption and diffraction are more frequently used due to better precision. Although they are complex and expensive, they pronounce an important feature like non-destructive character. For particular cases geometrical conditions and mathematical calculation procedure must be elaborated. An application of X-ray diffraction in grazing incidence angle for thickness determination is described in this article. The method is based on absorption principles of X-ray beam. The absorption is proportional to thickness of the coating and to incidence and to the diffraction angle which. Geometrical conditions were obtained experimentally and suitable mathematical calculations were introduced. The elaborated methodical approach was applied to thickness determination of copper coatings electrodeposited on a brass substrate.

Abstract: The non-destructive structure characterisation of surface layers for various kinds of ball bearings can be a powerful method in surface characterization and in quality control. The ball bearings were made of 100Cr6 steel and they were superfinished and mechanically burnished. An application of classical X-ray diffraction sin2ψ method and classical Bragg-Brentano diffraction geometry in these kinds of surface examinations make some problems in term of X-ray real depth of penetration. An application of methods based on grazing angle X-ray diffraction geometry, made possible to get real value of residual macro-stresses, retained austenite and additionally could be suitable in estimation of their gradient-like distribution versus depth under surface. An application of this geometry to X-ray diffraction phase analysis enabled to get phase contents versus thickness under surface in non-destructive way as well. The results are not infected by gradient-like distribution. The X-ray quantitative phase analysis was used to establish volume fraction of transformed retained austenite. Theoretical calculation of residual macro-stresses due to volume fraction of transformed austenite in ball bearings and following measurements of residual stresses were curried out as well. The mechanical burnishing of ball bearings caused big compressive residual stresses about – 1000 MPa and phase transformation of austenite in thin surface layer. These factors can influence on properties of following exploitation and durability.