Analysis of Geometry Deviations in Case of Conical Mini-Parts Obtained by Forming Process from Copper-Zinc Alloy (CuZn37) Sheets

Abstract:

Mini forming is an appropriate technology to manufacture small metal parts, as these are required in many industrial products resulting from mini-technology. This paper work want to underline the fact that even in down scale there are problems regarding deviation from the required dimensions. One of the problems is scaling effects, which occur in tribological aspects such as the friction coefficient, which increases with decreasing specimen size. Simulations investigations into mini forming process were carried out and mini conical parts have been obtained with different geometries. . The main objective is to observe and quantify behaviour of the mini parts during forming process and geometry deviations that affect the final product. The material used in this analysis is copper - zinc alloy with anisotropic properties. During forming process of conical mini-parts, the material record important variation along the part length and generate important shape deviation. This phenomenon causes deviations of sidewall angle, superior diameter, inferior diameter, mini part height, and connection radius between the part bottom and sidewall. There are multiple factors that affect the geometry deviations: sidewall angle, friction coefficient, tools gap, punch radius, and punch speed. The Dynaform 5.9.1 software was used to simulate the forming process. The part obtained after each simulation was analyzed and measured to quantify the deviation from the desired geometry on the final conical mini-part. In the final part of this paper some conclusions regarding geometry deviation of conical mini-parts obtained by forming are presented.

• Periodical: Applied Mechanics and Materials (Volume 657)
• Pages: 158-162
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.657.158
• Online since: October 2014
• Authors: Robert Stefanut Teaca*, Gheorghe Brabie
• Keywords: Conical Mini-Parts, Copper-Zinc Alloy, Forming, Geometry Deviation

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