Papers by Author: Piotr Wiecinski

Abstract: The aim of the work was to optimise the Hydrostatic Extrusion, HE, parameters in terms of their influence on the microstructure and certain mechanical properties of 6082 aluminium alloy. The investigations focused on the fabrication of a nano- or ultrafine-grained microstructure of the alloy. The effects of a multi-pass process were compared with those of a one-pass process producing the same cumulated true strain of 3.75. Both the multi-pass and the one-pass deformation resulted in profound grain refinement of the alloy. The microstructure contained grains with an average size of 195 nm and 239 nm, respectively. The grain refinement brought about a significant improvement in the microhardness and tensile strength of the alloy. It should be noted that the multi-pass HE produced slightly greater improvement than the single pass process.

Abstract: The paper presents the results concerning the microstructure of Ti – Al intermetallic layers produced on a TA6V titanium alloy by the “duplex method”. This method combines vacuum evaporation coating of aluminum with glow discharge assisted heat treatment of the deposited films. It has been found that this combination of surface engineering techniques yields multi – layered films of the diffusive character. The films contain intermetallic phases from Ti – Al system which ensure a high microhardnes and good wear resistance. It is finally suggested that these properties can significantly widen application range of titanium alloy parts in aerospace.