The melting curve of cobalt under high pressure. (February 2020)

• Record Type: Journal Article
• Authors: Wang, Junpu; He, Duanwei; Li, Xin; Zhang, Jiawei; Li, Qiang; Wang, Zhiwei; Su, Yuzhu; Tian, Yi; Yang, Jing; Peng, Bo
• Is Part Of: Solid state communications. Volume 307(2020)
• Publication Date: 2020-02
• Subjects: Transition metals -- High pressure -- Characterization -- Melting; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2019.113805
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: The new melting curve of cobalt (Co) was determined to be 12 GPa using the in situ high-pressure temperature measurement method (HPTM) in a high-volume cubic press using two melting criteria: first, plateaus in the temperature vs power functions in situ experiments, and second, the texture changes in the samples before and after high-pressure high-temperature (HP-HT) treatments with a scanning electron microscope (SEM). The slope of the melting point with increasing pressure was approximately 33 K/GPa in our experimental pressure range and progressively decreased under further compression. Our new melting curve of Co under high pressure is reasonably consistent with the simulation results using one-phase and two-phase calculations and has a similar trend with the reported melting curves of Fe and Ni. Highlights: We show the in situ high-pressure temperature measurement method in the large volume cubic press that was an effective and simple method to measure the melting point. Two melting criteria were used: firstly, plateaux in temperature vs. power functions in in situ experiments and secondly, the texture changes for the samples before and after high-pressure high-temperature treatments with a scanning electron microscope. The slope of melting point with increasing pressure was found to be about 33 K/GPa in our experimental pressure range and progressively decreases under a further compression. Our new melting curve of Co under high pressure is reasonably consistent with the simulation results using one-phase and two-phase calculations and has a similar trend with the reported melting curves of Fe and Ni.