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TY - THES AU - Wolff, Nino Kornelius TI - Eine Untersuchung der verzugsbestimmenden Faktoren im Aluminium-Kokillenguss VL - 43 PB - Rheinisch-Westfälische Technische Hochschule Aachen VL - Dissertation CY - Aachen M1 - RWTH-2025-08578 T2 - Ergebnisse aus Forschung und Entwicklung / Gießerei-Institut der RWTH Aachen SP - 1 Online-Ressource : Illustrationen PY - 2025 N1 - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2026 N1 - Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2025 AB - An initial study of previous research on distortion formation in gravity die casting showed that there is hardly any holistic description. Deficits were also seen in the description of the heat transfer between mold and casting. In both cases, the various influencing variables and their respective proportions have not yet been considered in a coherent manner. The aim of this work is to gain a better understanding of the various influencing variables and their mechanisms of action on the formation of distortion in gravity die casting of aluminum through targeted experimental investigations. For this purpose, the causal chain of heat balance, mold constraint, solidification, cooling and stresses and finally the component distortion were considered individually and in context. In preliminary tests, the influences of various parameters on the heat transfer between the mold and the casting as well as their respective shares in the overall heat transfer coefficient were worked out. To investigate component distortion seven influencing factors were identified: temperature of the die, optimized temperature control channels, influence on the mold constraint by variation of the demolding temperature, influence of the mold constraint by thermomechanically different mold materials, influence of the component wall thickness, influence of component-immanent shrinkage hindrance (ribbing) as well as the influence of geometric compensation (retention). An experimental methodology was developed and corresponding tests were carried out to examine these influencing variables. The evaluation of the tests was carried out in addition to the consideration of the distortion by including in-situ measurement data, metallographic analyses and optical observations of the test castings. In addition to the amount of distortion, the stability of the process was also considered. For the individual influencing variables, it was found that the thermal interaction can essentially only influence the process stability. The distortion was influenced and largely compensated for by varying the demolding temperature and an empirical retention via the mechanical interaction and its established influence on the distortion. The mechanisms of action of the various influencing variables, their shares in component distortion and their time of influence in the context of the design and casting process were determined and subsequently discussed. A strategy for distortion compensation was derived from this. The findings obtained provide the broader knowledge base on the influences of distortion formation in aluminum gravity die casting that was aimed for in the objective. In combination with the experimental methodology developed in this work, this provides the basis for more targeted predictive distortion compensation. LB - PUB:(DE-HGF)11 ; PUB:(DE-HGF)3 DO - DOI:10.18154/RWTH-2025-08578 UR - https://publications.rwth-aachen.de/record/1019833 ER -