The application of conventional cooling lubricants for the tribological conditioning of machining processes involves high additional costs and health risks. The application of a cryogenic carbon dioxide (CO2) snow cooling strategy is an economical and environmentally sound alternative for oily cooling emulsions since it has a high cooling effect as well as a residue-free sublimation. This article introduces a laser additive manufactured tool holder with an integrated dual nozzle which enables CO2-snow jet application. Initially this work focuses on the characterization and the selection of a suitable nozzle geometry. The modular tool body features an adapted channel structure for process-reliable and targeted CO2-snow cooling for turning processes. This enables the simultaneous cooling of the rake and flank face with CO2-snow, as well as the application of cryogenic multi-component cooling of the rake face. In the context of this study, the focus lies on the technological evaluation of three different supply strategies during the continuous turning of compacted graphite iron CGI-450 at increased cutting speed. It was established that an efficient rake face cooling is indispensable to achieve a low thermal tool load, and thus lower crater wear behavior. Therefore, this study contributes to an improvement in cryogenic machining processes regarding the design of additively manufactured tool bodies for process-reliable CO2-snow cooling, as well as for the selection of supply strategies to minimize the thermomechanical tool load.

Additive Fertigungsverfahren gestatten die Herstellung innovativer Werkzeugsysteme mit erhöhter Funktionsintegration. Die vorliegende Arbeit liefert wichtige Erkenntnisse in Bezug auf additiv gefertigte Drehklemmhalter. Zum einen wird der Einfluss der Wärmebehandlung auf das Werkstoffgefüge und schlussendlich auf die Schwingfestigkeitseigenschaften untersucht. Zum anderen wird der Einfluss additiv hergestellter Zweistoffdüsen auf das resultierende Freistrahlverhalten experimentell ermittelt.   Additive manufacturing processes allow producing innovative tool systems associated with increased functional integration. This work provides important insights on additively manufactured turning tool holders. Firstly, it investigates how heat treatment affects both material structure and fatigue properties. Secondly, it determines experimentally how additively produced two-fluid nozzles influence the resulting open jet formation.

Vermiculargusswerkstoffe zählen zu vergleichsweise schwer zerspanbaren Werkstoffen im automobilen Antriebsstrang. Insbesondere kontinuierliche Schnittbedingungen stellen hohe Anforderungen an die eingesetzten Schneidstoffe. Kryogene Kühlverfahren können einen entscheidenden Beitrag zur Verlängerung der Werkzeugstandzeit von Hartmetall- und diamantbasierten Schneidstoffen leisten. Der Fachbeitrag fasst die Untersuchungen zum Einfluss der Prozesskühlung auf die Werkstoff- und Spanbildungseigenschaften zusammen.   Compacted graphite iron (CGI-450) with its excellent mechanical properties has a large and still increasing importance in the field of construction materials, especially in the field of automotive powertrain applications. The choice of tungsten carbide and diamond-based cutting tools with suitable technological constraints and different cooling strategies in view of chip formation, chip shape and cutting energy are to be illustrated in the following tests.

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Im Motorenbau werden vermehrt hochfeste Vermiculargusswerkstoffe mit hervorragenden mechanischen Eigenschaften eingesetzt. Die Zerspanbarkeit von Gusseisen mit Vermiculargrafit (GJV) stellt jedoch eine große Herausforderung dar. Die nachfolgenden Untersuchungsergebnisse verdeutlichen die Auswirkungen der Werkstoffcharge und der technologischen Randbedingungen auf das Einsatzverhalten von polykristallinen Diamantschneidstoffen.   Higher strength cast iron materials with improved mechanical properties are used for the construction of automotive engines. Especially machining of compacted graphite iron (CGI) is challenging for the manufacturer. This paper deals with the impact of different material batches in case of CGI-450 and with the effect of varied technological boundary conditions on tool life of polycrystalline diamond cutting tools.