Nitrogen Solubility in Liquid Ni-V, Ni-Ta, Ni-Cr-V, and Ni-Cr-Ta Alloys

Qian Qian,Chen Chen,Shu Shu,Liu Liu

doi:10.3390/met9111184

Qian Qian, Chen Chen + Show 2 more

Open Access

https://doi.org/10.3390/met9111184

Copy DOI

Abstract

An investigation has been made concerning the solubility of nitrogen in liquid binary alloys (Ni-V and Ni-Ta) and ternary alloys (Ni-Cr-V and Ni-Cr-Ta) by sampling method. The experiments were carried out in the temperature range from 1773 K to 1873 K and under the nitrogen partial pressure up to 1.0 bar. A technique involving induction melting and a rapid quench device has been used in this study. It has been found that Sieverts’ law successfully describes the nitrogen dissolution in all these liquid alloys up to 1.0 bar of nitrogen gas partial pressure. The additions of vanadium, tantalum and chromium significantly increase the nitrogen solubility, especially vanadium-alloying addition. Furthermore, we have determined the interaction parameters, enthalpies and entropies of nitrogen dissolution in these liquid alloys.

Highlights

Nitrogen has consistently emerged as one of typical gaseous impurity elements in nickel-based super-alloys that generally imparts negative influences on mechanical properties of these alloys [1,2,3,4].In particular, small amounts of nitrogen can be very deleterious [5]
Nitrides have not been observed in liquid nickel-based alloys over nitrogen range from 0.1 to 1.0 bar during melting processes
It is obvious that the addition of V, Cr, Nb and Ta apparently increases the nitrogen solubility, and vanadium exhibits the highest increase of nitrogen

Summary

Introduction

Nitrogen has consistently emerged as one of typical gaseous impurity elements in nickel-based super-alloys that generally imparts negative influences on mechanical properties of these alloys [1,2,3,4].In particular, small amounts of nitrogen can be very deleterious [5]. Nitrogen has consistently emerged as one of typical gaseous impurity elements in nickel-based super-alloys that generally imparts negative influences on mechanical properties of these alloys [1,2,3,4]. Residual concentration of this element should be accurately controlled in the smelting process. It is of significant importance for both research and industry to get the information on the extent of the nitrogen solubility over specific ranges of gas pressure and temperature [6]. The method of investigating the solubility of a non-metallic impurity element (i.e., nitrogen, oxygen, sulfur, etc.) in metal melt in presence of a third element has been widely applied to determine the interaction parameters [7,8]

Methods

Results

Discussion

Conclusion