Kunčická Lenka, Jopek Miroslav, Kocich Radim, Dvořák Karel
Institute of Physics of Materials, Czech Academy of Sciences, Žižkova 22, 616 00 Brno, Czech Republic.
Department of Metal Forming and Plastic, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, 616 69 Brno, Czech Republic.
Materials (Basel). 2021 Aug 25;14(17):4821. doi: 10.3390/ma14174821.
Tristal steel is low-carbon construction-type steel widely used in the automotive industry, e.g., for braking components. Given the contemporary demands on the high-volume production of such components, these are typically fabricated using automatic sequential machines, which can produce components at strain rates up to 10 s. For this reason, characterising the behaviour of the used material at high strain rates is of the utmost importance for successful industrial production. This study focuses on the characterisation of the behaviour of low-carbon steel via developing its material model using the Johnson-Cook constitutive equation. At first, the Taylor anvil test is performed. Subsequently, the acquired data together with the results of observations of structures and properties of the tested specimens are used to fill the necessary parameters into the equation. Finally, the developed equation is used to numerically simulate the Taylor anvil test and the predicted data is correlated with the experimentally acquired one. The results showed a satisfactory correlation of the experimental and predicted data; the deformed specimen region featured increased occurrence of dislocations, as well as higher hardness (its original value of 88 HV increased to more than 200 HV after testing), which corresponded to the predicted distributions of effective imposed strain and compressive stress.
三晶钢是一种低碳建筑用钢，广泛应用于汽车工业，例如用于制动部件。鉴于当代对这类部件大批量生产的要求，这些部件通常使用自动顺序加工机床制造，这些机床能够以高达10 s的应变速率生产部件。因此，表征所用材料在高应变速率下的行为对于成功的工业生产至关重要。本研究通过使用约翰逊-库克本构方程建立其材料模型，重点研究低碳钢的行为特征。首先，进行泰勒砧座试验。随后，将获取的数据以及测试试样的组织结构和性能观察结果用于向该方程中填入必要的参数。最后，使用所建立的方程对泰勒砧座试验进行数值模拟，并将预测数据与实验获取的数据进行关联。结果表明实验数据与预测数据具有良好的相关性；变形试样区域的位错出现频率增加，硬度也更高（测试后其原始值88 HV增加到200 HV以上），这与有效施加应变和压缩应力的预测分布相对应。
