The study relates to a process of continuous rotary extrusion (CRE), also known under the name of a Conform Process. This method is used more and more extensively for the plastic working of metals and alloys. In CRE, the feedstock is fed into a profiled groove on the rotating extrusion wheel and is pressed by the pressing wheel. The friction of the extruded material against the rotating wheel generates a force that is pushing the material into the deformation chamber followed by extrusion through the die orifice. The extrusion by CRE was performed on an MC-260 device supplied by Meltech-Confex and installed at IMN - OML for processing of the 6063 aluminium alloy. The feedstock was composed of annealed rods. Two parameters were controlled during extrusion: the temperature of the shoe (element of the housing pressing the extruded material to the wheel) and the speed of the driving wheel. The 6063 alloy was extruded using the wheel speed of 2, 5, 10 and 15 rpm and the shoe temperature of 90°C and 105°C. The extruded flat sections were examined visually for continuity and quality of the resulting surface. In the feedstock rod and in the extruded flat sections (before and after heat treatment), the microstructure and grains were examined by light microscopy. Mechanical properties were also determined (static tensile test and hardness measurement). The study shows how the structure and the mechanical properties of the extruded flat sections are changing depending on the extrusion parameters applied. From the 6063 alloy rods extruded by CRE, flat sections of satisfactory quality were obtained. It was found that CRE yields the highest mechanical properties combined with the correct structure and high surface quality when the feedstock is extruded with the wheel rotational speed of 10 rpm and the shoe temperature of 105°C.

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Heat treated aZ61 MagnesIuM alloy obtaIned by dIrect extrusIon and contInuous rotary extrusIon processThe results of studies carried out on the heat treated AZ61 magnesium alloy extruded by two methods, i.e. direct extrusion and continuous rotary extrusion, were presented. As part of the work, parameters of the T6 heat treatment were proposed and aging curves were plotted. The solution heat treatment process was accompanied by the grain growth. During artificial aging, due to the decomposition of solid solution, the β-Mg17Al12 phase was precipitated from the supersaturated α solution. It precipitated in a coagulated form at the grain boundaries and in the form of fine-dispersed plates arranged in a preferred direction relative to the grain orientation. Rods obtained by continuous rotary extrusion, unlike those made by the direct process, exhibited a low degree of texturing and lack of anisotropic properties.

One of the methods to produce aluminium alloys of an uncommon composition and structure is by the combined process of casting with rapid solidification and the following plastic forming.When modern advanced methods of rapid cooling of the melt are used, the alloy structure solidifies as a powder in the atomiser or as ribbons when cast onto a rapidly rotating copper wheel. If optimum conditions for the process of casting and rapid consolidation are satisfied, it is possible to control some structure parameters like the size of the particles, the size of the precipitates, etc. Additionally, the production of aluminium alloys by rapid solidification allows introducing the alloying constituents that are incompatible with the state of equilibrium. The consolidation of material made by rapid solidification is achieved in one of the numerous variations of the plastic forming processes, among which the most commonly used are the direct extrusion and continuous rotary extrusion (CRE).This paper presents the results of the consolidation in the process of continuous rotary extrusion (CRE) of selected aluminum alloys with an unusually high content of alloying elements cast in the process of rapid solidification by melt spinning and crushed in a high-speed cutting mill to as "chips".Keywords: aluminium alloys, continuous rotary extrusion, melt spinning process Jednym ze sposobów otrzymywania stopów aluminium o nietypowym składzie i strukturze jest połączenie odlewania metodą szybkiej krystalizacji z przeróbką plastyczną.W przypadku zastosowania nowoczesnej metody szybkiego chłodzenia ciekłego metalu struktura stopu krystalizuje w postaci proszków w atomizerze lub w postaci tasiemki na szybko obracającym się miedzianym kole. Jeżeli spełnione są odpowiednie warunki prowadzenia całego procesu szybkiego odlewania i konsolidacji wtedy możliwa jest kontrola paramertów struktury takich jak wielkość ziarna, wielkość wydzieleń itp. Dodatkowo wytwarzanie stopów aluminium metodą szybkiej krystalizacji umożliwia wprowadzanie składników niezgodnych zestanem równowagowym. Konsolidację materiału otrzymanego w procesie szybkiej krystalizacji przeprowadza się w procesach przeróbki plastycznej, najczęściej stosowanymi są proces wyciskania lub proces ciągłego wyciskania na kole.W pracy przedstawiono wyniki badań dotyczących konsolidacji metodą ciągłego wyciskania na kole (CRE) wybranych stopów aluminium o nietypowo wysokiej zawartości składników stopowych odlanych metodą szybkiej krystalizacji na kole (meltspinning) i rozdrobnionych w szybkoobrotowym młynku tnącym do postaci "chipsów" (płatków).

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