2022/02/18 by Pedro P. Ferreira, Felipe M. Carvalho, Ferreira, Pedro P. +20
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Fire effects on concrete materials #Materials Science (cond-mat.mtrl-sci) #Metal Alloys Wear and Properties #Microstructure and Mechanical Properties of Steels #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.2202.09197
7 pages, 4 figures
arxiv created 2022/02/18 · openalex publication_date 2022/02/18 · arxiv updated 2022/02/21 · openalex created_date 2022/05/05 · openalex updated_date 2026/08/03
The development of new fire-resistant steels represents a challenge in materials science and engineering of utmost importance. Alloying elements such as Nb and Mo are generally used to improve the strength at both room- and high-temperatures due to, for example, the formation of precipitates and harder microconstituents. In this study we show alternatively that the addition of small amounts of boron in Nb-microalloyed steels may play a crucial role in maintaining the mechanical properties at high temperatures. The 66 % yield-strength criteria for fire resistance is achieved at ≈ 574 °C for a boron steel, whereas without boron this value reaches ≈ 460 °C, a remarkable boron-induced mechanical strengthening enhancement. DFT calculations show that boron additions can lower the vacancy formation energy when compared to pure ferrite and, for Nb-B steels, there is a further 24 % reduction, suggesting that the boron-niobium combination acts as an effective pinning-based strengthening agent.