Experimental and numerical investigation on cold flat rolling processes of DC04 sheets with special focus on residual stresses

18th Chemnitz Seminar on Materials Engineering – 18. Werkstofftechnisches Kolloquium

Bauer, A.^1,2 ; Mehner, T.^2 ; Binotsch, C.^1 ; Sieber, M.^2 ; Awiszus, B.^1 ; Lampke, T.^2

Department of Virtual Production Engineering, Institute for Machine Tools and Production Processes, Technische Universität Chemnitz, Chemnitz

09125, Germany^1

Materials and Surface Engineering Group, Institute of Materials Science and Engineering, Technische Universität Chemnitz, Chemnitz

09125, Germany^2

关键词: Cold flat rolling;    Distribution of residual stress;    Manufacturing process;    Numerical investigations;    Rolling temperature;    Semi-finished products;    State of the art;    Stress orientations;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/118/1/012019/pdf
DOI  :  10.1088/1757-899X/118/1/012019

来源: IOP

【 摘 要 】

The process of cold flat rolling is a widespread industrial technique to manufacture semi-finished products, e.g., for the automotive or homewares industry. Basic knowledge of the process regarding dimensioning and adjustment of defined characteristics is already state of the art. However, a detailed consideration and analysis with respect to local inhomogeneous residual stresses in several process steps mostly remains disregarded. A broad understanding of the process due to the distribution of residual stresses in the workpiece and the direction of the stress tensors allows for a definition of the characteristics of the workpiece even before the actual manufacturing process. For that purpose, it is necessary to perform numerical investigations by means of the finite element analysis (FEA) of cold flat rolling processes. Within this contribution, several approaches for the calibration of the FEA with the real flat rolling process will be addressed and discussed. To ensure that the numerical consideration provides realistic results, this calibration is indispensable. General parameters such as geometry, height reduction, rolling temperature, process time, and the rolling speed are considered as well as a photogrammetric survey, and calculated residual stresses with results of X-ray diffraction (XRD) will be compared. In the course of the experiments, a good agreement between the stress results of the FEA and the XRD was found in the center of the specimen. In combination with the allocation of the stress orientations, the agreement close to the edges is also fine. Some issues that cause differences between the FEA and the experiment are dis-cussed.