Direct observation of Face-centered cubic zirconium phase growth-induced stacking faults in Zr3Ge secondary phase nanoparticle

Zr3Ge secondary phase particles (SPPs), frequently observed in the Ge-modified Zirconium alloys, greatly affect their corrosion resistance. Considering that stacking faults (SFs) in SPPs may affect their stability, the observation of SFs formation in Zr3Ge has implications for these precipitation-strengthening zirconium alloys. In the present study, a faulted Zr3Ge SPP in close contact with a Face-centered cubic Zirconium (FCC-Zr) phase, has been investigated because of its locality and particular substructure. Based on the comprehensive analysis on the Zr3Ge SPP and its crystallographic orientation relationships with the surrounding phases, the formation mechanism of SFs in the Zr3Ge was discussed. Results revealed that SFs in the Zr3Ge were induced by the adjacent FCC-Zr phase. More specifically, the growth of FCC-Zr phase exerted mechanical stress on the nearby Zr3Ge in the {110} _Zr3Ge planes along [ 1 1 ¯ 1 ] Zr 3 G e direction. And this stress activated the synchroshear on the {110} _Zr3Ge planes, thereby producing SFs in the Zr3Ge SPP.