Metastable phase formation in rapidly quenched Zr80Pt20 alloys: Linkage to oxygen

Melt spun Zr80Pt20 ribbons having oxygen contents ranging from <200 to ≈5000 mass ppm are shown to form various metastable phases during quenching. In the presence of sufficient oxygen, a big cube Zr6Pt3O phase forms, but this structure is de-stabilized towards an icosahedral quasicrystalline structure at lower oxygen levels. Further reduction of oxygen promotes increasingly stable ZrPt bonds, and a metastable β-Zr(Pt) structure is formed.