Job description

In Germany, refrigeration accounts for 17% of electricity consumption. Cooling on a small scale, as it is required, e.g., in electronic chips, lab-on-chip systems, chemical and biological analysis, is often performed by miniaturization-compatible thermoelectric cooling, which is however rather in-efficient. A promising alternative is elastocaloric cooling based on stress-induced temperature changes, e.g., in superelastic shape memory alloys (SMAs), which exhibits no environmental impact associated with leakage of the solid refrigerant (i.e., zero GWP), and is highly efficient with material’s efficiency close to the thermodynamic maximum limit. Elastocaloric cooling has therefore been identified by the U.S. Department of Energy and later by the EU Commission as the most promising non-vapor-compression technology for future cooling.

This PhD position will develop a zero-carbon, zero-electricity elastocaloric cooling device, with a particular emphasis on the use of renewable energy and/or the recovery of waste heat for future sustainability. This innovative approach is expected to utilize low-temperature heat sources below 200°C, enabling "free cooling". This project is particularly promising for thermal managements in miniature-scale applications, including microelectronic chips, smart actuator-sensor systems, and temperature control of bioanalytical chips.

The position focuses on research in the following subjects:

• Material characterization of shape memory alloys material properties (mechanical, thermal, fatigue life)
• Design of a demonstrator concept of elastocaloric microcooler and shape memory microactuator
• Design, orders, production of the elastocaloric microcooling device using microtechnologies (lithography, etching, 3D printing, laser cutting)
• Characterisation of the microcooling demonstrator and evaluation of measurement results

In executing this position, the IMT is equipped with an expansive array of state-of-the-art facilities, including a 600 m² clean room, advanced rapid prototyping capabilities like 3D printing and laser cutting, Construction and Connection Technology labs, as well as various metrology laboratories. A high level of support is provided to ensure that the project progresses seamlessly within the specified timeline. The position is within the Next Generation Cooling division of Dr. Jingyuan Xu

Personal qualification

-    An excellently completed scientific university education (master) in the mechanical engineering field
-    In-depth knowledge of thermodynamics, heat transfer, microsystems technology and mechanical engineering
-    Interested in the production of cooling prototype using smart materials
-    Ability to work in a team and enjoy working in international research groups
-    Good written and spoken English knowledge.

Contract duration

limited for 3 years

Technical contact person

Dr. Jingyuan Xu, email: jingyuan.xu∂kit.edu.