Dr. Aritra Sarkar

Current professional background:

I am presently working as a postdoctoral researcher at University of Siegen supported by the Alexander-von-Humboldt research fellowship. I originally work as a scientist at Indira Gandhi Centre for Atomic Research, India since 2010 and finished my Ph.D through JSPS RONPAKU fellowship from Nagaoka University of Technology, Japan.

 

Field of research:

My research work is mainly in the area of high cycle fatigue (HCF) and damage interaction between low and high cycle fatigue (LCF-HCF interaction) on austenitic stainless steels and Ni-based superalloys commonly used in power plants. I am actively involved in characterizing deformation mechanisms under such loadings, which are critical issues for the reliability of structural components. Based on the test data, I have generated design curves at high temperatures (Haigh diagram) and devised new methodologies for modification of fatigue design rules.

 

Purpose of your last research visit:

My research at University of Siegen is focussed on very high cycle fatigue (VHCF) which is a topic of significant interest in view of the present technological developments, particularly from the viewpoint of life-extension of structural components which are subjected to vibratory stresses during the operation. My aim is to re-evaluate the S-N curves extending to the VHCF range involving the effect of prior LCF cycling, which simulate the actual loading scenario, so that components experiencing such multi-level loading can be designed more accurately.

 

Relation to the University of Siegen and/or to the local host:

I became aware of Prof. Christ’s pioneering work from the beginning of my career due to the strong research collaborations between IGCAR and University of Siegen. So, when I decided to work on VHCF, the Chair of Materials Science and Testing at University of Siegen became almost a natural choice. It is a great experience working here and I thank prof. Christ for giving me this opportunity.

 

Future projects / Activities:

On returning back to IGCAR, I plan to expand my work on HCF/VHCF on austenitic stainless steels, especially how multi-level loading influences VHCF and developing suitable modelling approaches based on the test data. I look forward to future collaborative visits at University of Siegen to carry out VHCF tests at high temperature where damage mechanisms become more complex with synergistic effect of creep, oxidation etc. on cyclic loads.

 

Impressions of Siegen:

Siegen (Weidenau) is a nice city with hilly landscape and beautiful sceneries around. Its very comfortable living here. The winter seems to be tougher though, especially for us who are more accustomed to a warmer climate.