The influence of chromium addition on the environmental embrittlement of Ni 3(Si,Ti) alloys at ambient temperatures

Abstract

The environmental embrittlement in ordered intermetallics as well as ordinary materials is caused via some microscopic processes involving the decomposition, absorption, permeation and condensation of hydrogen atoms in the associated region, and finally by the bond breaking of the materials. Therefore, it is expected that the substitutional solutes are also capable of influencing the environmental embrittlement of Ni{sub 3}(Si,Ti) alloys by affecting a microscopic process differently than boron and carbon do. In this study, it is shown that the embrittlement of Ni{sub 3}(Si,Ti) alloys in air is suppressed by the addition of chromium at a level of one atomic percent. The embrittlement/ductilization behavior and the associated alloying effect are characterized by the tensile tests at room temperature in several environmental media and strain rates, and the fractographic observation.