Cold metal forming is a fast and economical way of producing a wide range of precise components. Its profitability mainly depends on part quality, process stability and service intervals of tools. As these factors are all determined by tool wear, detailed process knowledge is indispensable to maximize profitability by minimizing wear. One of the most crucial factors in this context is temperature. During every forming process, a temperature rise occurs between tool and workpiece due to frictional heating and a large part of plastic work dissipating into heat. This temperature affects the whole forming process but especially tool wear. Currently, there is little solid information about temperatures occurring during forming operations. Therefore, the temperature was measured based on varying process parameters in several embossing and blanking examinations. The use of a tool-workpiece-thermocouple enabled accurate and instantaneous measurement during the process. The results presented show the strong influence of process parameters on temperatures in the forming zone.

Almost every metal mass product goes through a blanking process. Especially when processing aluminum, adhesive wear is the main determinant of cost efficiency. Many investigations on wear-influencing factors have been conducted so far, but one major determinant is almost unnoticed, thermoelectric phenomena. Due to the Seebeck effect, thermoelectricity arises in every blanking tool. Recently published investigations show that the combination of tool and workpiece materials has a strong influence on occurring thermoelectric currents and thus on adhesive wear development. This can be traced back to dependence of the current strength and direction on the materialspecific Seebeck coefficient. This article addresses the same phenomenon for a new parameter spectrum. Blanking experiments with aluminum EN AW 5083 were performed, investigating both thermoelectric currents and the amount of adhesive wear. Furthermore, the impact of external currents influencing the naturally occurring thermoelectricity on wear is shown. Improved measurements with a laser confocal microscope reveal a close correlation between the thermoelectric current profiles and adhesive wear pattern on the lateral surface of the punch. Together with a variation of tool material among highspeed steel 1.3343, stainless steel 1.4301 and cemented carbide CF-H40S, a strong relation between the Seebeck coefficients, electrical currents and tool wear could be found. Therefore, the actual findings confirm, deepen and extend previous results concerning thermoelectricity and adhesive wear.

Cold metal forming is a fast and economical way of producing a wide range of precise components. Its profitability mainly depends on part quality, process stability, and service intervals of tools. As these factors are all determined by tool wear, detailed process knowledge is indispensable to maximize profitability by minimizing wear. One of the most crucial factors in this context is temperature. During every forming process, a temperature rise occurs between tool and workpiece due to frictional heating and a large part of plastic work dissipating into heat. This phenomenon affects the whole forming process but especially tool wear. Currently, there is little solid information about temperatures occurring during forming operations. Therefore, the temperature was measured based on varying process parameters, sheet materials, and thicknesses in several embossing and blanking examinations. The use of a tool–workpiece thermocouple enabled accurate and instantaneous measurement during the process. The results presented show the strong influence of process and material parameters on temperatures in the forming zone.

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Availability, sustainability, and functionality pose particular challenges for the value chain of individual mobility. Therefore, in this work, the typical value chain is broken up and the traditional approaches are extended with an open-source perspective. The focus is on modularity and simplicity in order to enable the broadest possible applicability and fast implementation of local production. Nevertheless, the mobility concept should meet the current standards, especially with regard to safety. A modular vehicle frame is presented as a basis, which meets all regulations, can be built in self-assembly, and is available as open-source.