Understanding the role of Er on glass-forming ability parameters and critical cooling rate in Fe‒based multicomponent bulk metallic glasses

• Published in: Journal of alloys and compounds 2020-04, Vol.819, p.152938, Article 152938
• Main Authors: Deshmukh, Akash A., Khond, Anuj A., Bhatt, Jatin G., Palikundwar, Umesh A.
• Format: Article
• Language: English
• Subjects: Alloys; Amorphous materials; Cooling; Cooling rate; Critical cooling rate; Critical diameter; Erbium; Glass formation; Glass forming ability; Iron; Metallic glasses; Parameters; Supercooled liquid region
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.152938

In this paper, the role of a lanthanide element, Erbium (Er) on the glass-forming ability (GFA) parameters such as Trg, ΔTx, α, γm, ε, γ∗ and critical cooling rate (RC) of previously reported Fe‒based multicomponent (Fe0.9Co0.1)65−xMo14C15B6Erx (x = 0.125,0.25,0.50,0.75,1,2) BMGs has been studied. With varying Er from x = 0.125 to 0.75, it is observed that the critical diameter (ZC) of the alloy was increased from 2.0 mm to 4.0 mm whereas ZC decreased to 1.5  mm at x = 2.0. Our study also shows that the width of the supercooled liquid region (SLR) reduced from 61 K to 42 K as x varies from 0.125 to 2.0. For x = 0.125 and 0.50, SLR was found to be maximum as 61 K. From x = 0.125 to 0.50, it was observed that Tg, Tx, and Trg were found to increased and attains maximum value. Moreover, for x = 0.75 to 2.0, these parameters were decreased linearly. Similarly, α, γm and ε were found to decrease linearly whereas γ∗ and PHSS were increased linearly from 0.125 to 2.0. Moreover, with the increase in Er content, the RC of the alloy was increased linearly. Alloys Fe57.05Co6.45Mo14C15B6Er0.5 and Fe57.825Co6.425Mo14C15B6Er0.75 were found to have maximum ZC of 4.0 mm and large SLR of 55 K and 57 K, respectively. These alloys were found to have a low cooling rate among others. Finally, it was found that the presence of Er in the range of x = 0.50 to x = 0.75 has a positive effect on ZC and SLR along with low RC. •Compositional dependence of Er with glass forming ability (GFA) parameters and critical cooling rate (RC) was evaluated.•Inverse correlation of GFA parameters α, γm and ε were found with Er. Whereas γ∗ and PHSS have shown linear relation with Er.•Appropriate amount of Er addition was found to improve the GFA of the Fe-based BMGs.•Cooling rate (RC) was increased with increase in Er content.•Low RC was obtained for the composition having large reduced glass transition temperature and large supercooled liquid region.