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The paper presents the results of mechanical properties testing of thin sheet metal of INCONEL 625 and 718 alloys. These studies are a continuation of experience in the preparation of the technological characteristics of metal strips plasticity necessary for carrying out numerical simulations [1]. In order to process sheets now become necessary to design the process using software such as thermo-mechanical simulation e.g. Eta/DYNAFORM. On the road of numerical simulation are sought optimal conditions for processing sheets. It brings reducing the cost of industrial tests. However, becomes strictly necessary characteristics of mechanical and technological properties describing the characteristics of the charges for forming. Here the problem is solved if we forming limit curves (FLCs) designated and technological tests conducted. Using the FLCs is comprehensively defined stamping sheet metal press formability and technological tests allow the mapping of the actual operating conditions selected stamping operations. In the presented study used modern digital analyzer AutoGrid of local deformations and the method of image analysis of deformed mesh subdivision. The use of mesh analyzer and vision systems method significantly speeds up the possibility of producing FLCs. Also measurement accuracy is very high. Selected Inconel alloys are evaluated quantitatively and qualitatively by preparing their properties characterization. The acquired data entered into the database material properties of sheet metal and used in the numerical simulation of stamping process of Inconel 625 cone drawpiece. The legitimacy of the use of modern strain analyzer AutoGrid has been confirmed.

Mechanical working manufacturing methods of nickel alloys used conventionally strips and blanks need to solve many problems concerning high strength material forming which is characteristic limited plasticity. The production pressed elements of vehicle constructions and aircraft engine elements requires the high quality drawpieces since these are essential for safety. They are also the main structural components. Conventional methods of mechanical working such as pressing can be used in quantity production of the above mentioned elements and their production can also be cost-effective. Forming nickel alloys generates a lot of technological wastes resulting from back-springing effects determining the most appropriate pressure in the process of pressing. Failure holes in the process of bulging as well as cracking of drawpieces in the process of deep drawing. The heterogeneous mechanical properties distribution on thin sheet blanks made of Inconel alloy, which is different than material quality certificate shows, produces also a lot of manufacturing problems. These problems are usually solved by production engineers in the following way: dividing the production of ready drawpieces into a bigger number of simple blank profiling operations, shallow pressing, using a rubber punch for pressing or hydroforming. Complex drawpieces shapes are quite often made of several parts which are next welded. In the case of presented tube a tubular diffuser made of Inconel 718 alloy blank and cone made of Inconel 625. However the process of forming high strength materials like nickel alloys requires the application bigger forming forces than in the same kind of conventional formable steel processes. Tools get jammed quite often in the process and high force presses of 10 MN or more need to be used so is very expensive. The aspect of cold mechanical forming discussed materials has been a particular interest. The researches based on precise evaluation mechanical properties and technological plasticity of the selected materials in basic mechanical and technological tests as well as in FEM numerical simulation (finite elements method). The material models applied to simulation contain the pointed out experimentally the mechanical characteristics of Inconel alloys. The thin sheets blanks made of 0,9 mm thick Inconel 718 alloy and 0,45 mm thick Inconel 625 alloy blanks have been examined. The possibilities of using numerical simulations for solving the problems of selecting or modifying the pressing technology and hydroforming that type materials as well as forecasting the results of forming processes have been also presented. The evaluation of drawability of thin sheets blanks made of Inconel 718 and 625 alloys has also been discussed in the paper.

The paper presents the results of a study of drawability of thin AZ31 magnesium alloy metal sheets. These studies are a continuation of experiences in presenting the characteristics of technological plasticity of strips made of magnesium alloy which have been cast between rolls in vertical and horizontal systems called ‘twin-roll casting’. In the context of previous experiments conducted at the Institute of Material Technology of the Silesian University of Technology in cooperation with the Technical University - Bergakademie Freiberg (Germany), drawability of these strips at elevated temperatures has been comprehensively defined while using forming limit curves. Due to low formability of magnesium alloys at ambient temperature, formability tests - including cup forming tests presented in this paper - have been carried out in heated dies at temperature range of 200°C to 350°C. A modern AutoGrid digital local strain analyzer has been used in the examinations and the method of image analysis of deformed coordination nets has been applied. Quantitative and qualitative impact of deformation temperature upon the drawability effects of AZ31 magnesium alloys products have been evaluated.

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The paper presents the study of drawability of thin sheet metals made of a nickel superalloy Inconel type. The manufacturing process of axisymmetric cup -cone and a closed section profile in the form of a circular tube were designed and analyzed. In both cases, working fluid-oil was used in place of the rigid tools. The process of forming liquid is currently the only alternative method for obtaining complex shapes, coatings, and especially if we do it with high-strength materials. In the case of nickel superalloys the search for efficient methods to manufacture of the shaped shell is one of the most considerable problems in aircraft industry [1][2][3][4][5]. However, the automotive industries have the same problem with so-called advanced high-strength steels (AHSS). Due to this, both industrial problems have been examined and the emphasis have been put on the process of liquid forming (hydroforming). The study includes physical tests and the corresponding numerical simulations performed, using the software Eta/Dynaform 5.9. Numerical analysis of the qualitative and quantitative forecasting enables the formability of materials with complex and unusual characteristics of the mechanical properties and forming technology. It has been found that only the computer aided design based on physical and numerical modeling, makes efficient plastic processing possible using a method of hydroforming. Drawability evaluation based on the determination of the mechanical properties of complex characteristics is an indispensable element of this design in the best practice of industrial manufacturing products made of thin sheet metals.