In the aluminum sector as well as in the manufacture of semi‐finished products, there are numerous industrial examples for combinations of casting and forming processes. In the past, the processes usually were considered separately. However, with the development of digital technologies, it has recently become possible to jointly simulate casting and forging processes and set up continuous process simulations. In the manufacturing of steel components, such a combination is not known industrially. The present paper describes a forged steel component based on a cast preform. To predict the expected properties, the necessary simulations were linked, whereby the focus of the investigations is on the principle feasibility and methodology of such a combination. Based on the conditions assumed in the simulations, test components were manufactured. The simulation results, especially voids and porosity were compared with the real components. In addition, the microstructure of the components was investigated. Approaches for further investigations and the improvement of the combined simulation are presented.

The development of an innovative hybrid lightweight piston for marine engines is intended to help reduce emissions and operating costs. The piston consists of a piston base and a top part. In the manufacture of the piston base a preform is cast and the final geometry is produced by means of subsequent forming (forging). This significantly improves the mechanical properties of the material. As a result of the possible material advantages in the overall process chain, the piston base can be designed as a “lightweight component”. By examining the entire process chain of “primary casting - forging", the amount of used materials is significantly reduced, especially in the “casting” production route, since even minor internal defects can be tolerated after the preform has been cast. For the subsequent forging process, this material pre-distribution thus represents an optimum initial forging shape. The upper part of the piston is made of a layered composite material. Here, the special material is already applied to the blank prior to the forging process by laser or PTA build-up welding. This means that the filler material is also formed together with the base material, which in turn has a positive effect at the mechanical properties. This is followed by a heat treatment, which further improves the high temperature resistance. Due to the higher strength and corrosion resistance of the piston head, the temperature and pressure of the combustion chamber can be increased, enabling the required reduction of emissions and fuel.

Casting and forging are among the technologies with the highest material and energy requirements. Many efforts have been made to minimise the expenditures involved, but in most cases they have been limited to the individual application case. While the combination of casting and forming processes has been described and applied extensively for aluminium components, this approach has been far less investigated and advanced for steel components. The latest developments in the software with a direct interface between casting and forming simulation enabled the creation of a continuous simulation from the casting to the finished forged part. The match between the simulation and the real component was verified on the basis of manufactured sample parts. Currently ongoing investigations focus on the formation of the microstructure in the component. At the same time, the process chain casting - forging is being developed and evaluated for a further component. This approach overcomes existing limits and opens up new possibilities for component design by linking simulations of casting and forging technologies into an integrated continuous process chain simulation.

The need for cooperation between humans and industrial robots is in exponential increase, especially in production applications. However, human safety is the main concern, preventing any fenceless cooperation between humans and industrial robots. This paper presents elements of new strategy for ensuring human safety during various levels of interaction with heavy-load industrial robots. The proposed approach classifies the human–robot interaction (HRI) into four levels. In every level, different kinds of safety functions are developed and analyzed. An additional algorithm has been developed for classifying the dangerous during the interaction. The proposed approach is tested and analyzed on a HRI platform.

Forming processes are generally characterized by a high degree of material utilization as well as short process times and, consequently, a decent economic efficiency. Considering their application in the manufacturing of large spur gears, forming processes offer a significantly attractive characteristic for the production of essential gearing components commonly used in wind turbines or marine engines. Furthermore, the hot forming process can be defined as an incremental forming process which enables the use of relatively low forming forces and results in a more compact design of the used machines. These conveniences are utilized in terms of roll forming with round tools to form gears and threads in a competitive way. Based on experiences gained over many years of researching rolling technologies, a cross-rolling process characterized by round tools with outer gearings was elaborated to realize a hot forming process for gear rolling of large spur gears at the Fraunhofer IWU Chemnitz. Based on the already researched forming of smaller dimensioned gears, rolling trials utilizing a new hot-forming machinery - including defined inductive heating process before rolling - to realize large gears with outer diameters of up to 1000 millimeters were conducted. In terms of realizing this ambition, the derivation of the designated machine parameters for rolling large gears in real-life dimensions can be defined as a crucial factor. Consequently, the experimental research was followed by a mathematical analyzation of the forming forces, momenta as well as the necessary steps to determine the best possible scaling factors for the work pieces.

Forming processes are generally characterized by a high degree of material utilization as well as short process times and, consequently, a decent economic efficiency.Furthermore, incremental forming enables the use of relatively low forming forces which results in a more compact design of the used machines.These conveniences are utilized in terms of roll forming with round tools to form gears and threads in a competitive way.Based on experiences gained over many years of researching rolling technologies, a cross-rolling process characterized by round tools with outer gearings was elaborated to realize a hot forming process of large gears at the Fraunhofer IWU.At actual project GEARFORM, a scaled sun gear demonstrator from wind gear application could be realized by hot rolling technology.An optimized rolling time was achieved by 32.5 seconds.

Forming by gradation extrusion enables severe plastic deformation with a large gradient of plastic strain resulting in a correlating gradient of the microstructure. Materials with tailored properties can thus be provided. Controlling the gradation of the microstructure also requires knowledge of the interaction of forming process and a special die geometry. Based on an analytical calculation approach, different geometry variants are characterized. Additionally, selected geometrical variants are studied more comprehensively by numerical simulation. The mechanisms of the interaction and possibilities of influencing the deformation process by die design and process parameter optimization are presented and analyzed.

Designing material characteristics by grain refinement using Severe Plastic Deformation (SPD) is an attractive way to create outstanding material properties. This paper presents a unique method which combines SPD and impact extrusion. The extrusion die is designed to create additional material deformation to a defined depth, resulting in a gradient from ultra-fine grained to coarse grained microstructure. Due to the large gradient the method is called gradation extrusion. The paper presents a new analytical calculation method and a numerical evaluation of the strain, showing the relationship between tool design and achievable effects and provides initial experimental results.

The need for even greater efficiency in handling resources is coming to be seen as a public duty in politics, commerce and research. At the same time this raises the question of what options are open to companies in the manufacturing industries - and, in particular, the OEMs and suppliers to the automotive industry - for reducing costs as well as deployment of resources and emissions. In addition to illustrating and analysing the relevance of this topic as far as forming technology is concerned, the following article discusses a selection of approaches that are being adopted in the Fraunhofer Institute for Machine Tools and Forming Technology with a view to reducing the consumption of resources, particularly in the bodywork parts production sector.