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Mg-3Sn-2Ca (TX32) alloy has good creep resistance but limited workability. Minor amounts of Al and Si have been added to TX32 for improving its hot workability. The processing map for the TX32-0.4Al-0.4Si alloy exhibited two workability domains in the temperature and strain rate ranges: (1) 310-415°C/0.0003-0.003 s and (2) 430-500°C/0.003-3 s. The alloy exhibited flow instability at temperatures < 350°C at strain rates > 0.01 s. The alloy has been forged to produce a cup shape component to validate these findings of processing map. Finite-element (FE) simulation has been performed for obtaining the local variations of strain and strain rate within the forging. The microstructures of the forged components under the optimal domain conditions revealed dynamically recrystallized grains, and those forged in the flow instability regime have fractured and exhibited flow localization bands and cracks. The experimental loadstroke curves correlated well with those obtained by FE simulation. [ABSTRACT FROM AUTHOR]

Roll-forging process is widely used to fabricate the automobile front axle beams. The reasonable selection of the process parameters is significant to ensure the quality and improve the property of the automobile front axle beam owing to the complexity and importance of the preliminary roll-forging process. This paper developed a 3D Finite element (FE) model of the preliminary roll-forging process of the AISI-1045 automobile front axle beam under the Deform-3D platform. A corresponding experiment is subsequently conducted. Good agreement between the experimental and simulative results validates the employed model. Based on this dependable FE model, the influences of initial temperature of billet T, rotational speed of rolls n and friction factor m on the geometric dimension, temperature inhomogeneity, deformation inhomogeneity, and roll-forging load are investigated comprehensively. The results can provide reliable guidelines for the selection of process parameters. [ABSTRACT FROM AUTHOR]

During industrial forging of hot metallic shells, it is necessary to regularly measure the dimensions of the parts, especially the inner and outer diameters and the thickness of the walls. A forging sequence lasts 2 h or more during which the diameter of the shell is regularly measured in order to decide when to stop the forging process. For better working conditions, for the safety of the blacksmiths, and for a faster and more accurate measurement, we have developed a novel system based on two commercially available time of flight laser scanners for the measurement of the diameters of hot cylindrical metallic shells during the forging process. The advantages of using laser scanners are that they can be placed very far from the hot shell, more than 15 m, while at the same time giving an accurate point cloud from which three-dimensional views of the shell can be reconstructed and diameter measurements done. Moreover, more accurate measurement is achieved in less time with the laser system than with the conventional method using a large ruler. The system has been successfully used to measure the diameters of hot cylindrical metallic shells. [ABSTRACT FROM AUTHOR]

Preform design is an important aspect of the research and development of the forging processes, which plays a key role in improving product quality, such as improving material filling capacity and reducing forming loads. In industry, preforms are generally designed by the iterative trial-and-error approach. This approach, however, leads not only to the increase of tool cost but also to prolonged production time. On the basis of the minimum energy principle and the minimum resistance law, a new approach by means of 3D electrostatic field simulation and geometric transformation is proposed in this paper to design the preform shape. Two axisymmetric (a disk and a blind-hole) forgings and a long-axis part are used to demonstrate this method, and finite element package DEFORM 3D is used to simulate the forming process for the purpose of verifying the validity and effectiveness of this approach. [ABSTRACT FROM AUTHOR]

Squeeze casting is a hybrid metal forming process combining features of both casting and forging in one operation. This paper reports a research in which an attempt was made to prepare solid cylindrical components of LM24 aluminum alloy through squeeze casting. The primary objective was to investigate the effect of process parameters on the mechanical properties exhibited by the castings produced though squeeze casting process. A set of trials were conducted based on parameters settings suggested in Taguchi’s offline quality control concept. The experimental results indicate that the squeeze pressure and the die-preheating temperature were the parameters making significant contribution toward improvement in mechanical properties of squeeze cast LM24 aluminum alloy. [ABSTRACT FROM AUTHOR]

In this work, a comprehensive study of radial forging process is presented through 2-D axisymmetric and 3-D finite element simulations while considering internal tube profile. The tube used in this investigation has four internal helical grooves along its length. The material is modeled with the elastic-plastic behavior, and sliding-sticking friction model is utilized to model the die-workpiece and mandrel-workpiece contacts. The numerical results in the 2-D case are compared with available experimental data. Residual stresses in the forged product, stress concentration around the grooves, pressure distribution on the hammers and mandrel and maximum forging load are studied. The effects of process parameters such as workpiece and die geometries, percentage of deformation, and workpiece motions on residual stresses and applied pressures on the hammers and mandrel are investigated. The results provide a valuable insight into the parameters affecting radially forged products and provide a useful tool for better design of this process. [ABSTRACT FROM AUTHOR]