Uncovering the mechanism of dislocation interaction with nanoscale (<4 nm) interphase precipitates in microalloyed ferritic steels

Materials Research Letters

David Cortie¹  Navjeet Singh¹  Elena Pereloma¹  Frank Niessen¹  Gilberto Casillas¹ 

[1] University of Wollongong;

关键词: interphase precipitation;    precipitation strengthening;    high resolution stem;    dft modelling;   

DOI  :  10.1080/21663831.2020.1764121

来源: DOAJ

【 摘 要 】

Nanoscale interphase precipitation in microalloyed ferritic steels provides a remarkable (200–400 MPa) strengthening increment, however its origin is unclear. Scanning transmission electron microscopy revealed step formation at the matrix/precipitate interface after both macroscopic uniaxial tension and nanopillar compression testing. Supported by Density Functional Theory modelling, dislocation shearing of nano-sized (<4 nm) VC precipitates was identified as a strengthening mechanism. The findings suggest the operation of an unusual {001}<110> slip–system in the VC nanoparticles.

【 授权许可】

Unknown