Abstract
The results of an investigation of the orientation relationships between adjacent plates of acicular ferrite are reported in an attempt to elucidate further the mechanism of acicular ferrite formation. Welds were made using the manual metal arc technique and the as-deposited microstructure of a high strength weld deposits was examined using crystallography and transmission electron microscopy. It was found that clusters of acicular ferrite form in such a way that adjacent plates tend to have a similar orientation in space; the reasons for this are discussed.
This research paper investigates the crystallographic orientation relationships between neighbouring plates of acicular ferrite found within high-strength steel weld deposits. By utilising transmission electron microscopy and diffraction pattern analysis, the authors discovered that these adjacent ferrite plates frequently share a similar spatial orientation.
The study suggests that this alignment occurs because sympathetic nucleation, where new plates form on existing ones, is energetically easier when the crystals are oriented similarly. These findings help clarify the transformation mechanisms of steel, specifically how microscopic structures organise themselves to minimise strain during cooling.
Ultimately, the work concludes that the observed grouping of plates is a predictable result of the austenite-to-ferrite phase transition process.
Materials Science and Technology 5 (1989) 93-97.
