Stress Corrosion Cracking of Ti and Ti-6Al-4V Alloy in Dinitrogen Tetroxide

Abstract

Abstract The stress corrosion cracking behavior of titanium and Ti-6Al-4V alloy in liquid N2O4 has been investigated from thermodynamic considerations and autoradiographic, chemical, and potential studies. Studies were concerned with the N2O4-H2O-O2 system which is believed to produce HNO3 and the N2O4-O2 system to cause stress corrosion cracking. A hydrogen embrittlement mechanism involving HNO3 in the commercial N2O4 appeared improbable. An electrochemical mechanism in which O2 plays a major role has been proposed.