Information für die Wissenschaft Nr. 65 | 14. Oktober 2016
Priority Programme “Compositionally Complex Alloys – High Entropy Alloys (CCA-HEA)” (SPP 2006)
The Senate of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) has established the Priority Programme “Compositionally Complex Alloys – High Entropy Alloys (CCA-HEA)” (SPP 2006). The programme will start in 2017 and is designed to run for six years. Applications are now invited for the first three-year funding period.
Recently, a novel class of metallic alloys, referred to as “high entropy alloys” (HEA) or “compositionally complex alloys” (CCA), has been introduced. These alloys consist of near-equiatomic concentrations of multiple metallic elements. As such, they fundamentally differ from conventional alloys, which commonly consist of a primary element with additions of secondary (alloying) elements in order to achieve desired properties. This new concept of alloy design with no base element opens up a huge multi-component space with significant technological potential and poses challenging scientific questions.
The aim of this Priority Programme is to develop CCA and HEA with outstanding mechanical properties or displaying unusual phenomena, which cannot be obtained in conventional alloys, or be explained by current textbook-level theory. Within this programme, alloys with five or more elements are targeted, each having a concentration between 5 and 35 at. %. Lower-order subsets of these alloys, namely binaries, ternaries and quaternaries, may be investigated in supporting roles only, in order to gain basic understanding of CCA and HEA. In order to optimise targeted materials properties, small additions of minor alloying elements such as C, B, Hf, Zr, Si, etc., are permitted.
The Priority Programme will comprise two branches:
- High entropy alloys, HEA, which are defined within this Priority Programme as single solid solution phases, preferably with simple crystal structures.
- Compositionally complex alloys, CCA, consisting of multiphase microstructures with two or more phases, which may include a solid solution phase.
The HEA branch aims at the achievement of a basic-scientific understanding of materials properties that are due to the high entropy effect:
- Identification of specific properties that occur as a consequence of the salient features of HEA.
- Repudiation of interpretations mistakenly ascribing properties as being specific to HEA.
- Fundamental understanding of the characteristic structural and microstructural features of HEA, with particular attention to their influence on mechanical properties.
The CCA branch will follow a more application-oriented approach. The aim is to identify and to tailor chemical, crystallographic or microstructural features that govern promising mechanical properties of CCA, making them attractive for future application. Alloys considered should have additional characteristics such as:
- Adequate room-temperature properties (including tensile ductility and fracture toughness).
- Ability to be produced in sufficiently large quantities (> 100 g and > 100 mm in size), which allow for conclusive determination of materials properties.
- Machinability, so that desired specimen geometries can be prepared.
In the CCA branch, special emphasis shall be placed on thorough characterisation of mechanical properties of the alloys, resulting in the need to include tensile testing. However, in order to support the application-oriented approach, hardness and compression testing may be used for initial fast screening, but should not be the main focus of a project. In addition to basic mechanical properties, the projects should focus on one or more of these areas:
- Mechanical behaviour at low, RT and elevated temperatures.
- Corrosion and oxidation resistance.
- Aspects concerning diffusion effects.
In general: A working hypothesis that is in line with the overall scientific aims of the Priority Programme should be clearly presented in each of the proposals. Projects that include the development of production routes new for CCA or HEA should pay careful attention to microstructural stability within the range of desired application temperatures.
Due to the central importance of microstructure and some misleading statements in literature, in both the CCA and the HEA branches, special care has to be taken to thoroughly analyse the chemical and structural nature of the phases present in the specimens and to accurately document the specimens’ history (e.g. processing and heat treatment conditions).
Synergistic Aspects: To maximise the scientific outcome of the Priority Programme, networking is essential to promote knowledge exchange between the different projects. Applicants are also highly encouraged to feedback knowledge obtained from research on HEA into research on CCA and vice versa, thereby increasing the chances of success in the identification and realisation of attractive materials properties. Collaborative research in joint projects is encouraged, including projects coupling simulations with experiments. While individual applicants are also eligible, great care should be taken to avoid a narrow focus of the project (e.g. microstructural characterisation divorced from any connection to relevant properties).
Restrictions: Projects primarily focussing on functional materials properties (e.g. magnetic or electronic properties, super-conductivity) will not be supported in the Priority Programme. Other important structural and physical materials properties, such as lattice parameters, thermal expansion, thermal and heat conductivity, may be studied. However, if these materials parameters behave in a regular way, they cannot be the main focus of a project. Projects applying established production routes or other techniques just for their own sake and without addressing a specific issue of CCA and HEA are not within the focus of this Priority Programme. Projects that are primarily theoretical in nature and do not include a significant experimental component, will not be supported.
Microstructures that are in a highly non-equilibrium state, e.g. metallic glasses, will not be considered. Only crystalline material will be considered in this Priority Programme. In certain cases, production routes with high cooling rates may be necessary. However, additional measures (e.g. heat treatment) need to be carried out in order to achieve a state close to equilibrium in the desired temperature range.
Proposals for the first three-year funding period must be submitted in English no later than 15 February 2017 via DFG’s “elan” portal, selecting “SPP 2006”. Please follow the guidelines 50.05 and 54.01 for project submission. Proposals by one applicant must not exceed 20 pages. Joint proposals may comprise five additional pages for each additional applicant. If you are using “elan” for the first time, please note that you need to get yourself and your institutional address registered before being able to submit a proposal. Also, if you are planning to move to a different institution (e.g. with a temporary position as a principal investigator) you need to get the new institutional address registered beforehand. Please make sure that all applicants of your project (in case there is more than one) start their registration at the latest two weeks before the submission deadline. The registration requests are handled manually by DFG staff.
Please notice the rules for publication lists: Beside the general bibliography, every proposal should include a list of up to ten publications that relate directly to the project, independent of the number of applicants. Further, the number of publications that may be listed in any academic CV is ten as well. These publications need to be classified as a) refereed publications (articles which at the time of proposal submission have been published or officially accepted by publication outlets with scientific quality assurance) or b) other publications (e.g. publications without scientific quality assurance).
The proposals will be evaluated in the course of a colloquium in Bayreuth with short talks and poster presentations, scheduled for 4 April 2017.
The DFG’s electronic portal “elan” can be found at:
Proposal guidelines and preparation instructions are outlined in DFG forms 50.05 and 54.01, which can be found on the DFG’s website at:
For scientific enquiries concerning the scope of the programme, contact the Priority Programme’s coordinator:
- Professor Dr.-Ing. Uwe Glatzel,
Metals and Alloys (Metallische Werkstoffe),
phone +49 921 55-555,
Further instructions on submitting a proposal are supplied by the DFG:
For scientific matters:
- Inka Müller, M.Sc.,
phone +49 228 885-2271,
- Dr.-Ing. Burkhard Jahnen,
phone +49 228 885-2487,
For administrative matters:
- Sergej Wachtel,
phone +49 228 885-2241,