Repair of embrittlement induced by different hydride configurations by dissolving partial hydrides using pulsed electric current

Abstract

The sudden brittle fracture of Ti, Zr and other metals caused by brittle hydride phase usually depends on the hydride network that provides the crack initiation and propagation path. Common hydride networks include continuous hydride configuration and grain boundary hydride configuration. In this study, pulsed electric current is used to effectively repair the embrittlement caused by continuous hydride configuration and grain boundary hydride configuration in pure titanium. The elongation of pure titanium with hydride configuration increased from 10% to about 20% after pulsed electric current treatment, with a certain degree of recovery of ultimate tensile strength. This is due to the dissolution of partial hydride after pulsed electric current treatment, and the hydride configuration is destroyed. Considering the introduction of pulsed electric current, hydride configuration in pure titanium is thermodynamically unstable, and the electromigration effect in kinetics also accelerates desorption of hydrogen atoms. The evolution of hydride configuration and desorption of hydrogen atoms are beneficial to the recovery of mechanical properties of hydrogenated pure titanium. In this study, the problem of hydride embrittlement caused by different hydride configurations in pure titanium was effectively repaired by pulsed electric current, which provided a new pathway and solution for dealing with the hydride induced embrittlement.