Modelling of transition from upper to lower bainite in multi-component system

Abstract

A model for estimating the upper to lower bainite transition has been developed for the iron-carbon-manganese-chromium-silicon alloy system by comparing the time required to decarburise a supersaturated bainitic ferrite platelet and that needed for the start of cementite precipitation in the ferrite. The problem is treated as a competition between the decarburisation time and the kinetics of cementite precipitation. Lower bainite is induced when the latter process is faster. The time for forming a volume fraction of 0.01 of the equilibrium amount of cementite is taken as the precipitation start time. The model was calibrated using experimental data from iron-carbon system, and verified with iron-carbon-manganese-molybdenum system and an experimental steel currently being developed for high-strength applications.

Modelling of size distribution of blocky retained austenite in Si-containing bainitic steels

“…Two Si-containing steels (Table 1) were used to produce the bainitic microstructure, the choice of these alloys was because of an ongoing study on high-strength bainitic steel [12–14]. Cylindrical samples () were heat-treated in a THERMECMASTOR-Z thermal mechanical simulator under a vacuum of about 10 −3 Pa, with the radial dilatation recorded by a laser precision measuring device.…”

Applying a Neural Network-Based Machine Learning to Laser-Welded Spark Plasma Sintered Steel: Predicting Vickers Micro-Hardness

“…A neural network that has one hidden layer (or ≤ 2 hidden layers) is usually known as a multi-layer perceptron or shallow neural network (SNN), usually trained by a back-propagation (BP) algorithm. It has, however, seen diverse applications in materials science, such as predicting materials properties [11][12][13][14][15][16][17][18][19][20][21].…”

Effect of manganese sulphide particle shape on the pinning of grain boundary

“…The purpose of the work presented here was to reveal the role of the particles in determining the austenite grain structure in the context of other work focused on predicting the transformation characteristics of such alloys. [13][14][15] Experimental details A commercial free-machining steel in the hot-rolled condition was supplied by Swiss Steel AG in the form of rods 32 mm in diameter, with the chemical composition as listed in Table 1.…”

“…The purpose of the work presented here was to reveal the role of the particles in determining the austenite grain structure in the context of other work focused on predicting the transformation characteristics of such alloys. 13–15…”