Characterization of Fracture Resistance of Optimized Ferritic and Bainitic Steel Grades with Special Focus on Shear Loading

Funding: ReCIMP
Contact: Dr.-Ing. Rickmer Meya

Car seat components are often subjected to shear loads.

Based on the anisotropy of the material and the type of shear test, a high deviation is observed in the shear fracture strain. With the aim to understand this deviation, the shear fracture resistance of a ferritic (S700MC) and a bainitic (HBS800) steel is determined using five different specimen geometries (see Figure a), while also considering their rolling direction. Additionally, numerical stress triaxiality investigations for four of these geometries show that, apart from the IPT specimen, the SMF specimen was the only geometry showing an almost ideal shear behavior during the test (η=L=0) (see Figure b). Experimentally, it is determined that HBS800 shows high anisotropy with the fracture strain being lower in the diagonal direction compared to the longitudinal (see Figure c). Up next, investigations to correlate the results with the triaxiality variance as well as a validation using an industry part are planned. Further, the influence of the equipment as well as the operator on the results has been analyzed (see Figure d).

a) Tested geometries, b) Triaxiality distribution, Influence of c) Anisotropy and d) Test conditions