Combustion behaviour and mechanism of a Cu-Ni-Mn alloy in an oxygen enriched atmosphere. (February 2020)

• Record Type: Journal Article
• Authors: Shao, Lei; Xie, Guoliang; Liu, Xinhua; Wu, Yuan; Yu, Jiabin; Wang, Yayu
• Is Part Of: Corrosion science. Volume 163(2020)
• Publication Date: 2020-02
• Subjects: Combustion behaviour and mechanism -- Precipitation -- Oxygen enriched atmosphere; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.108253
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: A. The different combustion behaviors of specimens solution treated at 880 ℃ and aged at 450 ℃ for different time are attributed to the diffusion pathways of Mn and O atoms during the reaction process. Mn atoms diffuse from the heat affected zone continuously to the melting zone, resulting in a component gradient, whereas Mn atoms are found to diffusing the nanometer-scaled Ni and Mn enriched regions to the reaction interface instead of the farther locations leading to a weaker component gradient of manganese atoms. B. NiMn precipitates are partially dissolved into the liquid phase due to the fairly high migration rate of liquid phase boundary and high reaction rate. Therefore, it can be seen from the increase of lattice distance that oxygen atoms are distributed in the Ni and Mn enriched areas in melting zone and heat affected zone of unburned zone for the aged specimens, which is totally different to the uniform distribution of oxygen in solution treated specimens. Highlights: An unusual phenomenon is found that the remaining length of solution-treated specimens is found to increase at an increased oxygen pressure, whereas those of the aged specimens shows no distinct dependency on the oxygen pressure. Different combustion behaviors of solution treated and aged samples are attributed to the diffusion pathways of Mn and O atoms during the reaction process. The content of liquid phase and the transferring velocity of alloy and oxygen atoms regarding to aged alloy are not sensitive with increasing oxygen pressures, since diffusion manner of Mn atoms is mainly affected by the precipitation of NiMn phase. Abstract: The combustion behaviour and underlying mechanism of a Cu-Ni-Mn alloy solution treated at 880 ℃ and aged at 450 ℃ for different time are studied. The oxidation of elements is found to follow the sequence of Mn→Ni→Cu. The remaining length of solution-treated specimens is found to increase under higher oxygen pressures, whereas that of aged specimens show no distinct dependency on oxygen pressures. The different combustion behaviors are attributed to diffusion pathways of Mn and O atoms, i.e., continuous diffusion of Mn atoms in the solution-treated samples and diffusion from the precipitates in aged ones.