Probably the most advantageous fabrication technology of tungsten heavy alloys enabling the achievement of required performance combines methods of powder metallurgy and processing by intensive plastic deformation. Since the selected processing conditions applied for each individual processing step affect the final structures and properties of the alloys, their optimization is of the utmost importance. This study deals with thorough investigations of the effects of sintering temperature, sintering time, and subsequent quenching in water on the structures and mechanical properties of a 93W6Ni1Co tungsten heavy alloy. The results showed that sintering at temperatures of or above 1525 °C leads to formation of structures featuring W agglomerates surrounded by the NiCo matrix. The sintering time has non-negligible effects on the microhardness of the sintered samples as it affects the diffusion and structure softening phenomena. Implementation of quenching to the processing technology results in excellent plasticity of the green sintered and quenched pieces of almost 20%, while maintaining the strength of more than 1000 MPa.

The aim of the work is to optimize the induction heating regime and propose a suitable deformation temperature for a pre-sintered powder-based tungsten heavy alloy workpiece subsequently processed via rotary swaging. The heating regime is designed with the help of numerical analyses and subsequent experiments. The first part of the study focuses on the theoretic background of the induction heating and comprises the development of a reliable induction heating model via performing electromagnetic simulations in two individual computational software packages (for verification). The second part of the study then involves the optimization of the heating regime using the designed numerical model. Last but not least, the predicted results are compared to the experimentally acquired results, and the optimized heating regime, applicable before experimental rotary swaging of the WNiCo workpiece, is proposed. The results of the microstructure analyses of the workpiece heated to the selected optimum deformation temperature of 900 °C showed that the designed induction heating procedure provided sufficient heating of the bulk of the workpiece (contrary to the lower swaging temperature), as the swaged microstructure featured well-deformed tungsten agglomerates. Furthermore, the analyses documented the high-quality oxidation-free surface of the particular workpiece (contrary to the higher swaging temperature).

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The study focuses on structure analyses, texture analyses in particular, of an Al/Cu clad composite manufactured by single and double pass of the twist channel angular pressing (TCAP) method. Microscopic analyses were supplemented with numerical predictions focused on the effective imposed strain and material plastic flow, and microhardness measurements. Both the TCAP passes imparted characteristic texture orientations to the reinforcing Cu wires, however, the individual preferential grains’ orientations throughout the composite differed and depended on the location of the particular wire within the Al sheath during extrusion, i.e., on the dominant acting strain path. The second TCAP pass resulted in texture homogenization; all the Cu wires finally exhibited dominant A fiber shear texture. This finding was in accordance with the homogenization of the imposed strain predicted after the second TCAP pass. The results also revealed that both the component metals exhibited significant deformation strengthening (which also caused bending of the ends of the Cu wires within the Al sheath after extrusion). The average microhardness of the Cu wires after the second pass reached up to 128 HV, while for the Al sheath the value was 86 HV.

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