진학프로석·박사 채용 접수 플랫폼

Effect of Oxides on Segregation During Steel Casting

Background / Project Details

The primary circuit of a nuclear reactor (pressure vessel, steam generator, pressurizer) is built from forged and welded low-alloy steel parts. The chemical composition of the cast ingots used for forging these parts is not uniform. Chemical heterogeneities, known as segregation, cannot be entirely removed during the manufacturing process. Consequently, forged parts exhibit local variations of chemical composition, which can significantly impact their mechanical properties.

Institut Jean Lamour (IJL) is recruiting a Postdoctoral Research Fellow to investigate the effects of oxides on segregation during casting of large steel ingots. Conventional research on segregation during steel casting focused on transport phenomena related to convection and density differences between solid and liquid phases. This project investigates the recent hypothesis that channel-shaped segregation patterns may form by a different phenomenon, the entrainment of solute-rich liquid by the motion of oxide particles during solidification. The post-doctoral research fellow will investigate this phenomenon using both experimental and computational methods available at IJL, in tight collaboration with industry.

The contract is for 18 months. The project is funded by ArcelorMittal Industeel, CEA, and Framatome.

Responsibilities

The post-doctoral research fellow will be responsible for the topic of oxide effects on segregation during steel casting, working in collaboration with permanent researchers of IJL and with the industrial partners. He/She will take a leading role in bringing the Large Ingot Simulator (LIS) – a novel lab scale experimental setup, currently at an advanced stage of development – to full operation and will pioneer its scientific applications. The LIS will replicate the thermal conditions of solidification found in the core of an industrial ingot, to reproduce the size and the morphology of the microstructures formed in various steel grades. The behavior of different types of oxide particles introduced into the LIS will be investigated to explain their possible role in the formation of channel segregations. Analysis of experimental characterization will be assisted by numerical simulations using in-house multiscale models of solidification.

Main Activities

• Design and development of experiments.
• Characterization of steel samples.
• Numerical simulation and data analysis.
• Writing of documentation and scientific articles.
• Reporting results to industrial partners.

Salary: Starting at 2600 € (gross) per month, depending on the experience of the candidate

Starting date: Immediately, or upon availability of the successful candidate.

How to apply: Send us an application including

• a motivation letter,
• a detailed CV,
• contact addresses of two referees.

Selected candidates will be interviewed by a selection committee.

Scientific contacts

Julien ZOLLINGER, julien.zollinger@univ-lorraine.fr
Miha ZALOŽNIK, miha.zaloznik@univ-lorraine.fr

Institut Jean Lamour, 2 allée André Guinier, BP 50840, F-54011 Nancy CEDEX