The ongoing global trend toward carbon dioxide emission reduction forced the automotive industry to design lighter and resource-efficient vehicle bodies, leading to the huge success of the press hardening process. [1][2][3][4][5] One reason for this success lies in the availability of thin-walled ultrahigh strength steel 22MnB5, which combines good formability and highest strength properties of 1500 MPa at a fully martensitic structure after press hardening at reasonable costs. [6,7] Since the first application in the automotive industry in 1986 as a side-impact beam, [8] the application field of 22MnB5 components increases continuously from B-pillar to roof rail reinforcement and other parts to enhance passenger safety. [9,10] The thermomechanical approach of press hardening allows the production of complex-shaped components with high dimensional accuracy, [11] excellent mechanical properties, and, at the same time, offers the opportunity for realizing tailored properties. [12,13] Although a time-temperature course of uniform austenitization and quenching in a cooled forming tool, Figure 1a, results in a homogenous fully martensitic structure with highest strength, a locally varying time-temperature course during the forming process, Figure 1b, enables the creation of a tailored distribution of microstructures, where mechanical properties are locally adjusted to perfectly meet the load profile, e.g., in case of crash-relevant components. [5,6] According to Ademaj et al., after uniform austenitization at 930 C but differential cooling of 22MnB5, zones following "route H" develop highest tensile strengths (1500 MPa) whereas zones following "route S" show lower tensile strength properties (614 MPa). [14] Both process strategies of Figure 1 are chosen for the current study with respect to the aforementioned investigations.This approach has been identified as a viable option to obtain lighter body structures through the ability to design load adapted structures and to combine contradictory requirements within one component. [14,15] A prominent example in car body structures is the B-pillar, in which the bottom section exhibits higher
Press hardened components have become widespread in the automotive industry in structural and crash-resistant applications, thanks to the combination of the complex shapes and high mechanical properties obtained. However, the press hardening of coated boron steel results in severe adhesive-based wear, with tool maintenance being required in as few as 3000 cycles. The current industrial implementation of press hardening is defined to work around this phenomenon. While this aspect has been studied by different authors, most of the literature deals with laboratory-scale tribosimulators, leaving an open question into how this knowledge transfers to macroscopic effects on the industrial process. In this work, wear in press hardening is studied by comparing the results obtained in laboratory conditions with a pilot-scale line, and finally, with wear mechanisms observed on industrial tools. The aim of this study is to consolidate the current knowledge about the micro-mechanisms involved, and to understand to what extent the existing tests reproduce the actual mechanisms observed in the press floor. The results show how material transfer mainly happens as an accumulation of dust compacted into initial defects on the tool surface. Moreover, this mechanism is effectively reproduced in laboratory tribosimulators and pilot environments, showing a similar morphology to wear on industrial tools. The work sheds light on the underlying causes of wear, and its potential mitigation strategies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.