Doktorand/Ph.D. student -- FE-simulation
FE-simulation of residual stresses and residual deformation in hardened steel sheet
SSAB produces and develops new materials with increasing higher strength, among these two-phase and martensitic steel grades. During manufacturing of these materials they are hardened by which the material is rapidly quenched from high temperatures. In connection to this quench, a martensitic phase transformation occurs, leading to volume changes. As the quench process is not fully homogeneous, by obvious reasons, the volume changes will be accompanied with an inhomogeneous deformation leading to flatness problems of the sheet. To obtain improved flatness, a cold-rolling operation is added after hardening. The extra process is not only costly it also reduces the ductility and forming capability of the sheet. SSAB regards this as a problem of strategic importance, why a PhD project is initiated focusing on simulation of the hardening process in order to gain increased understanding of which parameters are most important to control for obtaining a stable process. The project will be collaboration between Dalarna University, (HDa) Luleå University of technology (LTU) and SSAB Tunnplåt, Borlänge. The two universities have a strong coupling as professor Lars-Erik Lindgren and Dr Jonas Edberg, both at LTU are also working part-time at HDa.
Supervision
At LTU there is a long tradition of simulating manufacturing processes and describing the processed material. The tradition began in the mid 1970’s with welding of low alloyed steel and has since developed to describing several processes as hardening, heat treatment, rolling, straightening, thermal cutting, metal cutting etc, and whole production chains. The material descriptions have been extended from low-alloyed steel to high-alloyed steel and superalloys for the aeronautic industry. The early models were mostly empirical but today they are often based on dislocation density models coupled to microstructural models. Several projects have been performed on SSAB-material in collaboration with SSAB.
A graduate student is recruited to HDa. The work is primarily done at HDa and SSAB with assistance from LTU. Lars Troive, the industrial supervisor at SSAB, is also part time professor at HDa.
Start
During spring 2012 as agreed upon
Miscellaneous
The employment is for full time and is limited in duration according to “HF 5 kap 7 §”. The research work will be done at HDa Borlänge and at SSAB.
Information
For further information contact;
Professor Lars-Erik Lindgren, Luleå tekniska universitet
Lars-Erik.Lindgren@ltu.se, cell phone 070-343 42 09
Professor Lars Troive, SSAB Tunnplåt
lars.troive@ssab.com, cell phone 072-337 19 93
Ansökningshandlingar
Din ansökan med angivet ref nr DUP 2011/739 skall innehålla
- Brev med personlig presentation
- Meritförteckning (CV)
- Styrkta betygshandlingar
- Uppgift om referens
Sista ansökningsdag
Ansökan skall ställas till e-postadress platsansokan@du.se eller postadress Registrator, Högskolan Dalarna, 791 88 FALUN och vara inkommen senast 2011-11-21.
