The Microstructure Prediction during the Welding Process of Fe–C–Si Steel Using Physical and Numerical Simulation: A Comparative Study. Issue 9 (19th June 2022)

• Record Type: Journal Article
• Authors: Królicka, Aleksandra; Zalecki, Władysław; Kuziak, Roman; Szczepański, Łukasz; Kustroń, Paweł; Radwański, Krzysztof; Ambroziak, Andrzej
• Is Part Of: Steel research international. Volume 93:Issue 9(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-06-19
• Subjects: dilatometry -- heat-affected zones -- microstructures -- spring steels -- welding cycles -- welding simulation -- 55Si7 steel; Steel -- Periodicals; Steel -- Metallurgy -- Periodicals; 669.142
• DOI: 10.1002/srin.202200059
• Languages: English
• ISSNs: 1611-3683

Abstract

Abstract : Overall, medium‐carbon, multiphase steels subjected to welding processes can be described as difficult and require dedicated process conditions. In these investigations, an attempt is made to characterize the welding process of commercial 55Si7 steel with a high carbon equivalent (CE = 0.73). An experimental tungsten inert gas (TIG) welding process is performed by the use of preheating. Then, to understand and explain the processes during welding, a numerical (finite element method [FEM]) and physical (dilatometry) simulation is carried out. Measurement points located in the heat‐affected zone (HAZ) are selected based on the obtained data of thermal cycles. Significant differences in the results obtained with the three approaches are assessed and indicated. The cause of the discrepancies in the test results is also identified. The essence of the implementation of material data, which precisely defines the kinetics of phase transformation, is confirmed. A detailed analysis of the contribution of the phases is performed, together with their morphological assessment, as well as the hardness distributions are conscientiously compared. Moreover, it seems that the segregation of the chemical composition of austenite and the initial microstructure plays a crucial role in terms of the quality of the prediction. Abstract : The difficult‐to‐weld 55Si7 steel is subjected to experimental welding processes, which are compared with numerical simulation (finite element method) and physical (dilatometry). The results concerning the phases (fraction, distribution, morphology) and hardness are compared, and the reasons for the occurring incompatibilities are indicated. The added value of this work is also an experimental complete continuous cooling transformation diagram of 55Si7 steel.