Beneficial effect of stress superposition on damage reduction in trimming processes

Beneficial effect of stress superposition on damage reduction in trimming processes

WEIß Alexander, FELDE Alexander, LIEWALD Mathias, ZERFAß Helmut

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Abstract. Trimming processes are frequently used for the manufacturing of fastener heads and similar parts with high precision requirements for specific regions of the part. Compared to conventional cold forging processes, the desired geometry can be achieved with significantly lower forces. However, trimming of sharp-edged geometries often leads to a highly inhomogeneous material flow and stress state in the workpiece, resulting in crack formation at such edges. To address this shortcoming, superposition of compressive stresses can be used to reduce the damage in the trimming process significantly. In this paper, the beneficial effect of stress superposition on damage reduction in a trimming process of a splined part is presented. By means of a numerical investigation using the FE-software DEFORM 3D, the impact of compressive stress superposition on the damage respectively crack formation at the edges of a splined part was investigated. Afterwards, trimming dies were manufactured and experimental investigations with three different trimming die geometries and different preform geometries were conducted to manufacture the splined parts. The edges of the splined parts were then characterized with a digital microscope and compared to the numerical results.

Stress Superposition, Trimming, Damage Reduction, Crack Formation

Published online 4/19/2023, 10 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: WEIß Alexander, FELDE Alexander, LIEWALD Mathias, ZERFAß Helmut, Beneficial effect of stress superposition on damage reduction in trimming processes, Materials Research Proceedings, Vol. 28, pp 611-620, 2023


The article was published as article 66 of the book Material Forming

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