Corrosion behavior and phase formation of LaFe13 − xSixBy alloys. (5th September 2017)

• Record Type: Journal Article
• Authors: Xue, Jianing; Long, Yi; Wang, Yixu; Hu, Jie; Zong, Shuotong
• Is Part Of: Materials & design. Volume 129(2017)
• Page Start: 1
• Page End: 8
• Publication Date: 2017-09-05
• Subjects: Magnetocaloric alloys -- Corrosion -- Electrochemistry -- Microstructure -- Boride; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2017.05.016
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: The co-influence of B and Si on the formation of 1:13 phase and corrosion behavior of LaFe13 − x Six By alloys is investigated. 1:13 phase is found in as-cast LaFe11.6 Si1.4 B0.5, while there is no 1:13 phase in as-cast LaFe12.0 Si1.0 B0.5 with lower Si content. The addition of B in the LaFe13 − x Six By alloys is not helpful for the formation of 1:13 phase during the annealing process. B element prefers to form Fe2 B, rather than occupying interstitial sites in the crystal structure of 1:13 phase, which results in the decrease of the value of magnetic entropy change (| Δ S |). Corrosion behaviors of annealed LaFe11.6 Si1.4 By alloys are reported. The results show that the addition of B improves the corrosion resistance of the alloys. Polarization curves of single phase α -Fe, Fe2 B and 1:13 phase show that the potential difference between Fe2 B and 1:13 phase is lower than that between α -Fe and 1:13 phase, which lead to the enhancement of corrosion resistance. The corrosion of LaFe11.6 Si1.4 B0.3 is effectively suppressed, and the value of | Δ S | is only reduced by 28%. Graphical abstract: Highlights: Addition of B is not helpful for the formation of 1:13 phase in annealing process. B prefers to form Fe2 B rather than occupying interstitial sites in 1:13 phase. Corrosion resistance of annealed LaFe11.6 Si1.4 By is improved with more B content. The substitution of Fe2 B for α -Fe phase reduces the galvanic corrosion rate.