Method of recycling titanium scraps via the electromagnetic cold crucible technique coupled with calcium treatment

Abstract

In this study, the electromagnetic cold crucible (EMCC) technique coupled with a Ca treatment method was used to test its potential for recycling Ti scraps. Deoxidation of molten Ti scraps was studied at Ca concentrations ranging from 0 to 0.5 wt%. With the addition of Ca, the contents of O, C, and H in the Ti scraps decreased, whereas the N content increased. Ca-based compounds were only observed on the top surface of the Ti ingots. The grain size and hardness of the fabricated Ti ingots before and after Ca addition were similar among the specimens. Noticeably, the ultimate tensile strength and the strain at fracture of the fabricated Ti ingots significantly increased from 641 +/- 23 to 774 +/- 8 MPa and from 5.8 +/- 0.8% to 19.5 +/- 5.1%, respectively, with the addition of Ca. (C) 2017 Elsevier B.V. All rights reserved.