TY - JOUR

T1 - Deformation-induced martensitic transformation in AISI304 by cryogenic machining

AU - Fricke, Lara Vivian

AU - Gerstein, Gregory

AU - Breidenstein, Bernd

AU - Nguyen, Hai Nam

AU - Dittrich, Marc-André

AU - Maier, Hans-Jürgen

AU - Zaremba, David Simon Felix Demian

N1 - Funding information: The study has been supported by the German Research Foundation (DFG) within the research priority program SPP 2086 (grant project number 401800578). The authors thank the DFG for funding and intensive technical support.

PY - 2021/2/15

Y1 - 2021/2/15

N2 - In order to substitute a heat treatment to obtain a hardened subsurface, cryogenic machining can be used if the steels machined contain metastable austenite. To exploit the martensitic transformation, the mechanism of the deformation-induced martensitic transformation upon machining needs to be known. It was found that by lowering the machining temperature a martensitic transformation can be achieved in grains independent of the Schmid factor for a temperature of -196 °C. At higher temperatures, grains in preferred direction with higher Schmid factor tend to transform into martensite. Therefore, it is concluded that the temperature should be either low enough to achieve a sufficient martensitic transformation, or beforehand a texture could be produced prior to the machining process. Another possibility is to add a second machining step with a different tool cutting edge angle to activate the transformation in other grains.

AB - In order to substitute a heat treatment to obtain a hardened subsurface, cryogenic machining can be used if the steels machined contain metastable austenite. To exploit the martensitic transformation, the mechanism of the deformation-induced martensitic transformation upon machining needs to be known. It was found that by lowering the machining temperature a martensitic transformation can be achieved in grains independent of the Schmid factor for a temperature of -196 °C. At higher temperatures, grains in preferred direction with higher Schmid factor tend to transform into martensite. Therefore, it is concluded that the temperature should be either low enough to achieve a sufficient martensitic transformation, or beforehand a texture could be produced prior to the machining process. Another possibility is to add a second machining step with a different tool cutting edge angle to activate the transformation in other grains.

KW - Grain boundaries

KW - Kinetics at cryogenic temperatures of processes in materials

KW - Metal forming and shaping

KW - Nanostructured materials

KW - Phase transformation

UR - http://www.scopus.com/inward/record.url?scp=85097330931&partnerID=8YFLogxK

U2 - 10.1016/j.matlet.2020.129090

DO - 10.1016/j.matlet.2020.129090

M3 - Article

VL - 285

JO - Materials Letters

JF - Materials Letters

SN - 0167-577X

M1 - 129090

ER -