The paper contains the theoretical and experimental analysis of the impact of the drawing angle on the drawing process and the properties of low carbon steel wires. A multi-stage drawing wire rod with a diameter of 5.5 mm on a wire with a diameter of 1.0 mm has been carried out in two stages. The first one consisted of preliminary drawing wire rod for the wire with a diameter of 2.2 mm which was next subjected to the drawing process at a speed of 25 m/sec at the final wire with a diameter of 1.0 mm. The wires were drawn in conventional dies with drawing angle α = 3, 4, 5, 6, 7 degrees.For the wires drawn in respective variants, the investigation of the mechanical properties was performed and the amount of lubricant on the surface of steel wires was determined. Numerical analysis of the process of drawing in the Drawing 2D complemented the experimental studies.It has been shown that when drawing at high speeds, properly chosen the value of the angle of the working part of the die can improve the lubrication conditions and mechanical properties of steel wires.

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The article presents the results of a theoretical analysis of the manufacturing process of the deep sleeve with the bottom by means of a method of combining the indirect extrusion of a thick bush and broaching the blank through the conical die in one cycle of the stamp. The main advantage of application of the developed method for production of the sleeve is to reduce demand for energy and force compared to traditional methods of producing the deep sleeve. Moreover, the nature of the single operation of the extrusion process and extension of the sleeve eliminates the necessity of additional treatments: soft annealing, reheating the charge and reducing wall thickness of the sleeve by a second tool, which significantly reduce energy, labour and time consumption of production. Numerical calculations were performed in the Forge R 2D using plane state of strain and the obtained results allowed to determine the forces necessary for the process and the strain limit, as well as die geometry and impact velocity on the process tool.

. High quality of relatively cheap of semi-finished and finished products is achieved as a result of using non-waste manufacturing methods, which include e.g. the rolling, drawing and extrusion processes. The effective enhancement of production quality may be achieved by employing contemporary modelling and optimization methods in the design of new technological processes. In plastic working processes, during the design and optimization of new technologies, numerical modelling plays a crucial role. It brings about considerable time and material savings. It enables the determination of the basic parameters of processes and prediction of any possible gains or losses associated with the implementation of new technological solutions. The article reports the results of numerical modelling studies on the processes of combined extrusion of sleeves, where solutions were implemented, which allowed bottomless sleeves to be manufactured by these methods, without having to use the operation of mechanical cutting off the bottom formed after the extrusion process. In one of the cases, by using working tools of the appropriate design, a process of non-waste extrusion of a through sleeves was even achieved. The basic advantage of the proposed solutions is the single-operation nature of processes with a simultaneous reduction of the energy-force parameters compared to the traditional methods of manufacturing these types of products.Keywords: extrusion, complex extrusion, deep sleevesIntensywny rozwój przemysłu, zapewniający wysoką jakość produkcji, powinien odbywać się przy racjonalnym wykorzystaniu maszyn i urządzeń produkcyjnych, niskim zużyciu materiałów i energii na jednostkę produkcji oraz przy maksymalnej wydajności procesów. Wysoką jakość stosunkowo tanich półwyrobów i wyrobów uzyskuje się w wyniku stosowania bezodpadowych metod wytwarzania, do których zalicza się m.in. procesy walcowania, ciągnienia i wyciskania. Efektywne podwyższenie jakości produkcji może być osiągnięte drogą wykorzystania podczas projektowania nowych procesów technologicznych współczesnych metod modelowania i optymalizacji. W procesach przeróbki plastycznej podczas projektowania i optymalizacji nowych technologii niezwykłą rolę odgrywa modelowanie numeryczne. Zapewnia ono znaczne oszczędności czasowe i materialne. Pozwala na określenie podstawowych parametrów procesów i przewidywanie ewentualnych strat bądź zysków w związku z zastosowaniem nowych rozwiązań technologicznych. W niniejszej pracy przedstawiono wyniki badań modelowania numerycznego procesów złożonego wyciskania tulei, gdzie zastosowano rozwiązania pozwalające na wytwarzanie tymi sposobami tulei bez dna, bez konieczności stosowania operacji mechanicznego odcinania powstałego po procesie wyciskania denka. W jednym z przypadków poprzez zastosowanie odpowiedniej konstrukcji narzędzi roboczych osiągnięto nawet proces bezodpadowego wyciskania tulei przelotowej. Podstawową zaleta proponowanych rozwiązań jest jednooperacyjny charakter procesów przy jednoczesnym spadku parametrów energetyczno -sił...

Magnesium alloys are highly strain rate sensitive and exhibit good workability in a narrow forging temperature range. Consequently, parts made of these materials are usually forged with low-speed hydraulic presses, using specially designed tool heating systems in order to ensure near-isothermal conditions. This study investigates whether popular magnesium alloys such as Mg-Al-Zn can be forged in forging machines equipped with high-speed forming tools. Experimental upset forging tests on AZ31B, AZ61A and AZ80A specimens were conducted, using a screw press with a ram speed of 0.5 m/s and a die forging hammer with a ram speed at stroke of about 5 m/s. Test specimens were preheated to 350 °C, 410 °C and 450 °C. After the upset forging process, they were air- or water-cooled and then examined for their workability, hardness and grain size. To validate the results, a forging process for a producing handle was designed and modelled by the finite element method. Distributions of strain, temperature and fracture criterion were analysed, and energy and force parameters of the forging process were calculated. After that, experimental tests were performed on AZ31B and AZ61A specimens in order to determine mechanical properties of forged parts and examine their micro- and macrostructure. Results have demonstrated that AZ80A is not suitable for forging with either the screw press or the die forging hammer, that AZ61A can be press- and hammer-forged but to a limited extent, and that AZ31B can be subjected to forging in both forging machines analysed in the study.