Abstract
An inductive sensor developed by Philips ATC has been used to study in-situ the austenite (γ) to martensite (α′) phase transformation kinetics during tensile testing in an AISI 301 austenitic stainless steel. A correlation between the sensor output signal and the volume fraction of α′-martensite has been found by comparing the results to the ex-situ characterization by magnetization measurements, light optical microscopy, and X-ray diffraction. The sensor has allowed for the observation of the stepwise transformation behavior, a not-well-understood phenomena that takes place in large regions of the bulk material and that so far had only been observed by synchrotron X-ray diffraction.
Highlights
One of the key features of the metastable austenitic stainless steels (MASSs) is the TransformationInduced Plasticity (TRIP) effect [1]
This study presents a method based on an inductive sensor developed by Philips ATC (Drachten, The Netherlands) that allows for a simple and fast in-situ characterization of the formation kinetics of mechanically-induced martensite during tensile testing
The progress of the α′-martensite formation with the strain was studied by light optical microscopy (LOM), magnetization measurements, and in tensile-tested specimens interrupted different
Summary
One of the key features of the metastable austenitic stainless steels (MASSs) is the Transformation. Induced Plasticity (TRIP) effect [1]. In their annealed soft state, MASSs are fully austenitic (γ); they can be strengthened by grain refinement [2] and by its transformation into martensite (α0 ). Under the application of stress/strain [3,4] Depending on their composition, MASSs can be further strengthened by an aging treatment that induces the precipitation of strengthening particles in the martensite phase, as it is the case of maraging and precipitation hardening (PH) stainless steels [5]. Strain-induced martensite forms from austenite when this is subjected to deformation above its flow stress. Depending on the residual stress level in the material, the transformation may take place immediately after plastic deformation, which is known as stress-assisted transformation [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
