진학프로석·박사 채용 접수 플랫폼

We are seeking an experienced and highly motivated postdoctoral researcher to join our research team at the Chair of materials, science and technology and the Chair of solid mechanics and rheology of materials, Faculty of Mechanical Engineering, University of Ljubljana. The selected candidate will be involved in national and EU-funded projects where his/her main research efforts will focus mostly on the field of improving super-elastic shape memory alloys (SMAs) by advanced strengthening methods, buckling stability and elasto-caloric technology. The position will start in February-March 2025 and will be funded for three years, with possible extension.

Elasto-caloric (eC) technology is considered one of the most promising alternatives to vapor compression technology for a wide range of cooling and heat pump applications. It is based on the elastocaloric effect that occurs during the mechanical loading of superelastic shape memory alloys (SMA), also known as elastocaloric materials. When an elastocaloric material is mechanically loaded, it heats up (due to an exothermic austenitic-martensitic transformation), while it cools down during unloading (due to a reverse and endothermic martensitic-austenitic transformation). The cyclic loading and unloading (with intermediate heat transfer phases to/from the heat sink/source) of elastocaloric material can therefore ensure active cooling or heating. Although, the eC effect can be triggered by both tensile and compressive loading, the latter has important advantages in terms of fatigue. Under compression, however, eC elements tend to buckle. Furthermore, since eC conditions are highly demanding (high-cycle fatigue regime with high frequency and large strains), enhancing eC performance would be a priority.

In view of this, strengthening the functional and structural properties of NiTi alloys by LSP to improve the fatigue performance, reducing hysteresis losses and enhancing the biocompatibility, as the main objectives of the project, will present a major benefit in several SMA scientific fields. Further, implementation of optimized LSP treatment on thin/thin-walled, geometrically complex elements is extremely challenging and promising not only for scientific community but also for industrial applications, where longer service life is a major concern. Although LSP is already established as an advanced, clean and precise strengthening technology, “selective” LSP treatment to obtain a functionally graded thin-walled tubes or stents with varying grain size along the length of the sample is a challenging and demanding task. 

The work will take place, under the guidance of professors Uroš Trdan and Jaka Tušek, in an application-oriented laboratory within a young team and a stimulating environment, in collaboration with leading international institutions and industrial partners. The project will focus on improving the functional and structural properties of super-elastic shape memory alloys (SMAs). The research involves optimizing advanced strengthening methods, i.e. laser shock peening (LSP) and employing advanced characterization techniques to enhance the performance of SMAs. These improvements target improved corrosion resistance, biocompatibility, buckling stability, and fatigue life under dynamic loading conditions to be utilized in a custom-designed elastocaloric (eC) device developed within our research facilities.

Access to all the needed infrastructure and the state–of–the art equipment will be provided (XRD, XPS, AES, SEM/EDS, EBSD, FIB, TEM, electrochemical analyses etc.). Additionally, part of the research, if necessary, will be conducted through visits to partner institutions abroad (France, Japan, USA, Czech Republic, etc.)