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Forging is one of the main processes used to manufacture metal components for a broad range of applications. This occurs mainly because forged products are highly reliable and present superior mechanical properties. However, lately the competitiveness of forged products has been threatened, since the difference between their superior performance and the performance resulting from other processes has lessened continuously. This has obliged the forging industry to invest in optimizing its processes, saving in raw materials and energy. In this context, the use of numerical simulation of the forging process has become an increasingly reliable tool in seeking this optimization. This study uses the commercial software QForm 3D, version 3.2.1.1, to analyse two forging processes, one by hot forging and one by cold. In the case of hot forging, work on a component with axial symmetry is looked at from which a gear is machined. Currently the part is forged in three stages based on an initial billet with a 7.0 kg mass. Forging is performed in a 40 NM mechanical press with an initial temperature of 1200°C. The hot forging process is optimized and this results in a saving of about 5% in material. In the cold forging case it is shown that the process, as designed, results in laps in the final part, and in possible tool failure due to excess load. In both cases, the material used is DIN 1.7131 (16MnCr5) steel.

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Thin-walled tubes are applied in several industrial areas, as heat exchangers, shock absorbers, preforms to other metal forming processes, etc. In this study an experimental and theoretical investigation is performed involving tube end expansion, reduction and inversion processes using a die. The parameters that govern each process are investigated. A brief description of each process and a summary of the state of art are presented. The material employed in the experimental tests is an AISI 1010 carbon steel and all the work is carried out at room temperature. The theoretical investigation is done using FEM software QFORM 3D, version 4.1.5. In order to feed the software with realistic data stress-strain curves for the material were obtained by means of compression tests and the tribological conditions at the contact interface between the tube and the tools was estimated by means of ring compression method. The investigation on the tube end-forming processes focused mainly on understanding modes of deformation and on establishing formability limits for each of them. The results show that processes for end-forming of thin-walled tubes are successful only within a compact range of process parameters.

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CAE (computer aided engineering) evaluates the forging process virtually to optimize the industrial production. The numerical and experimental investigations of forging process of a hollow part are important in industrial point of view. This study has been focused on the development of a 3D elastic-plastic FEM (finite element model) of hot forging to evaluate the forming process of hollow parts. The validity of this method was verified through a laboratory experiment using aluminum alloy (AA6351) with medium geometric complexity. The distributions of effective strain, temperature, metal flow and strength were analyzed for two different initial workpieces (tubular and cylindrical). It was observed that both initial workpieces can be used to produce the final hollow part using the numerical simulation model. The results showed that the numerical analyses predict, filling cavity, calculated strength, work temperature and material flow were in agreement with the experimental results. However, some problems such as air trapping in the die causing incomplete filling could not be predicted and this problem was resolved experimentally by drilling small holes for air release in the dies.