Effect of cold deformation in quench and tempered medium-carbon steel bars microstructure

ARANDA, VIRGINIA HAYDEE; CARAZO, FERNANDO DIEGO; GARCÍA, LAURA NOEL; CELENTANO, DIEGO JAVIER; TOLLEY, ALFREDO

MATERIALS SCIENCE AND TECHNOLOGY

MANEY PUBLISHING

Lugar: London; Año: 2022

0267-0836

Tempered AISI 4140 steel bars were processed by cold drawing. An effectivedeformation of ≈0.9 was achieved. The quench and tempered, and the subsequentlydeformed microstructures were analysed by optical and transmission electronmicroscopy. Intralath, interlath and spherically-shaped carbides, were identified in bothcases. The deformed specimens revealed a mixed structure of thinned laths anddislocations cell-blocks composed of cell-block and cell boundaries. After thedeformation process, alignment and fragmentation of the carbides occurred, mainly ofthose located in lath boundaries what would explain the partial preservation of the lathboundaries after drawing as they would arrest the destruction of lath martensiteboundaries. These microstructural characteristics shall play an important role toenhance grain refinement in subsequent heat treatments.