Precipitation of H Phase in a High-Silicon Austenitic Stainless Steel

Abstract

The morphology and crystallography of H phase precipitated in a high-silicon austenitic stainless steel have been investigated. Precipitation occurred predominantly at the austenite grain boundaries, although matrix precipitation could be induced by deformation. Analysis of extracted residues suggested that H phase was a complex silicide approximating to Cr₁₂Ni₉Fe₂Si₆. The marked similarity with M₂₃C₆ has been noted and the problem of identification by electron diffraction outlined.