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Description
The application of embossed structures close to the sheet surface allows for work hardening to be introduced into sheet metal materials, leading to an improvement in their mechanical properties. So far, this was demonstrated in previous research work via tensile tests with differently embossed dual-phase steel specimens. Since tensile tests only reproduce uniaxial loading of the sheet metal material, no conclusions can yet be drawn about the property modification that can be achieved by near-surface embossing concerning real-life, multi-axial loading scenarios such as driving a car. To get a deeper knowledge about the loading behaviour of embossed components, it is therefore important to consider such multi-axial load cases. In the investigations reported in this paper, such a multi-axial load case was realized by testing embossed specimens of DP500, DP600 and DP800 using a bending device. The tests showed an overall improvement in the yield strength and a simultaneous decrease in the elongation at break on the investigated materials. Further, the tests indicated that lower-strength materials get more influenced by embossing than higher-strength materials. By simulating the process of embossing the bending specimens and a subsequent three-point bending test, an even deeper understanding of the material property modification could be generated. Foremost, the stress and strain of the embossed and bent specimens can be evaluated during the embossing and bending process.