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The M4F project brings together the fusion and fission materials communities working on the prediction of radiation damage production and evolution and their effects on the mechanical behaviour of irradiated ferritic/martensitic (F/M) steels. It is a multidisciplinary project in which several different experimental and computational materials science tools are integrated to understand and model the complex phenomena associated with the formation and evolution of irradiation induced defects and their effects on the macroscopic behaviour of the target materials. In particular the project focuses on two specific aspects: (1) To develop physical understanding and predictive models of the origin and consequences of localised deformation under irradiation in F/M steels; (2) To develop good practices and possibly advance towards the definition of protocols for the use of ion irradiation as a tool to evaluate radiation effects on materials. Nineteen modelling codes across different scales are being used and developed and an experimental validation programme based on the examination of materials irradiated with neutrons and ions is being carried out. The project enters now its 4th year and is close to delivering high-quality results. This paper overviews the work performed so far within the project, highlighting its impact for fission and fusion materials science. Peer Reviewed L. Malerba a,*, M.J. Caturla b, E. Gaganidze c, C. Kaden d, M.J. Konstantinovi´c e, P. Olsson f, C. Robertson g, D. Rodney h, A.M. Ruiz-Moreno i, M. Serrano a, J. Aktaa c, N. Anento j, S. Austin i, A. Bakaev e, J.P. Balbuena b, F. Bergner d, F. Boioli k, M. Boleininger l, G. Bonny e, N. Castin e, J.B. J. Chapman l, P. Chekhonin d, M. Clozel m, B. Devincre k, L. Dupuy g, G. Diego a, S.L. Dudarev l, C.-C. Fu g, R. Gatti k, L. G´el´ebart g, B. G´omez-Ferrer n, D. Gonçalves g, C. Guerrero a, P.M. Gueye n, P. H¨ahner i, S.P. Hannula o, Q. Hayat p, M. Hern´andez-Mayoral a, J. Jagielski m, N. Jennett p, F. Jim´enez a, G. Kapoor d, A. Kraych h, T. Khvan e,q, L. Kurpaska m, A. Kuronen r, N. Kvashin j, O. Libera s, P.-W. Ma l, T. Manninen o, M.-C. Marinica g, S. Merino a, E. Meslin g, F. Mompiou t, F. Mota a, H. Namburi s, C.J. Ortiz a, C. Pareige n, M. Prester u, R.R. Rajakrishnan t, M. Sauzay g, A. Serra j, I. Simonovski i, F. Soisson g, P. Sp¨atig v, D. Tanguy h, D. Terentyev e, M. Trebala o, M. Trochet g, A. Ulbricht d, M.Vallet g, K. Vogel d, T. Yalcinkaya w, J. Zhao r a Centro de Investigaciones Energ´eticas, Medioambientales y Tecnol´ogicas (CIEMAT), Madrid, Spain b Universidad de Alicante, San Vicente del Raspeig, Spain c Karlsruher Institut für Technologie (KIT), Karlsruhe, Germany d Helmholtz-Zentrum Dresden-Rossendorf Ev (HZDR), Rossendorf, Germany e Studiecentrum voor Kernenergie / Centre d’´Etude de l’´Energie Nucl´eaire (SCK CEN), Mol, Belgium f KTH Royal Institute of Technology, Stockholm, Sweden g Universit´e Paris-Saclay, Commissariat `a l’´Energie Atomique et aux ´Energies Alternatives (CEA), Gif-sur-Yvette, France h Institut Lumi`ere Mati`ere (ILM), Centre National de la Recherche Scientifique, Lyon, France i Joint Research Centre (JRC)- European Commission, Petten, the Netherlands j Universitat Polit`ecnica de Catalunya, Barcelona, Spain k Laboratoire d’Etude des Microstructures (LEM), Centre National de la Recherche Scientifique, Chˆatillon, France l United Kingdom Atomic Energy Authority (UKAEA), Culham, UK m Narodowe Centrum Badan Jadrowych (NCBJ), Swierk, Poland n Normandie Univ, UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Mat´eriaux, 76000 Rouen, France o Aalto University, Espoo, Finland p Coventry University, UK q Universit´e de Li`ege, Belgium r Helsingin Yliopisto, Helsinki, Finland s Centrum Vyzkumu ˇReˇz S.R.O. (CVR), ˇReˇz, Czech Republic t Centre pour l’´Elaboration Elaboration de Mat´eriaux et pour l’´Etude des Structures (CEMES), Centre National de la Recherche Scientifique, Toulouse, France u Institut za Fiziku, Zagreb, Croatia v Paul Scherrer Institut (PSI), Villingen, Switzerland w Middle East Technical University (METU), Ankara, Turkey

Anatase (TiO2) thin films were grown by non-aqueous sol-gel dip-coating using titanium (IV) n-butoxide as precursor and 1-butanol as solvent. High withdrawal speed of 4.7 mm/s in dip-coating resulted in defect free films of 100 nm average film thickness after subsequent heat treatments. According to scanning electron microscope and X-ray diffraction measurements, the films consisted of nanocrystalline anatase with 30 nm mean crystallite size. Refractive index n(λ) and extinction coefficient k(λ) were determined over the wavelength range from 200 to 1650 nm. The optical band gap of the film material was approximately 3.2 eV. The results showed very similar optical characteristics to those that are accomplished with chemically more reactive aqueous sol-gel processes. Furthermore, it was found that in addition to porosity, coordination number of Ti atoms to nearest oxygen neighbors is likely to have a significant role in explaining differences of optical properties between bulk anatase and thin film materials of the present work.

The surface pretreatments of the austenitic stainless steel and copper surfaces for the sol–gel coating were carried out by chemical, plasma electrolytic or CO2 cryoblasting techniques. With the austenitic stainless steel the smoothest surfaces were obtained with plasma electrolytic cleaning, after which the measured contact angles of water were clearly decreased revealing improved hydrophilicity. As well with the copper samples the smooth surface and improved hydrophilicity was obtained with the plasma electrolytic cleaning, but oxide layer formed to the copper surface immediately after the treatment. CO2 cryoblasting provided rough surface with wetting properties close to the original surface both for austenitic stainless steel and copper surfaces. CO2 cryoblasting provided best appearance for the copper surface because no oxidation happened with that treatment. XPS and SIMS studies showed that with the plasma electrolytic treatment the surface layer of the austenitic stainless steel enriched of chromium and the oxide layer formed on the surface was less than 10 nm thick. With the chemical cleaning and CO2 cryoblasting, the chromium enrichment to the stainless steel surface was less. However XPS and SIMS studies showed that chemical treatment provided thinner oxide layer to copper surface than plasma electrolytic treatment.

Wear of materials is a widely recognised industrial problem. The direct costs of wear failures, such as wear part replacements, loss of productivity as well as indirect losses of energy, and the increased environmental burden, are real problems in everyday work and business. The mineral industry is particularly susceptible to wear part consumption resulting in high expenses. In this study, the performance of various steel-based wear resistant powder metallurgical metal matrix composites (MMCs) was studied for mineral industry applications. The matrix of the composites consisted of various tool steels, manganese steel and martensitic steel and the reinforcements used were tungsten carbides (WC), titanium carbides (TiC) or cemented carbides (WC/Co). Hot isostatic pressing (HIP) was used for compacting the materials. The performance of composite materials was studied in a laboratory scale cone crusher wear test. Correlations between the wear behaviour and microstructure parameters, such as volume fraction and the size of the hard particles and spacing between hard particles were investigated. It was found that the most important parameters in this wear environment were the total volume fraction of the hard phase and the type of the hard phase. A necessary feature of the matrix material is that it is also resistant to abrasion.

Components in many industrial applications, such as in the chemical, energy, process, pulp and paper, transport, etc. industries are exposed to harsh conditions in terms of e.g. mechanical and environmental loads. These conditions induce severe wear and may cause functional problems in the operation of mechanical systems because of high friction, especially at medium to high temperatures. Wear may also cause material to crack off from the surface; dirt or other impurities on surfaces exacerbate the problems even more. Consequently, maintenance problems and a shortening of the lifespan of the equipment may occur. The damaged components may also lead to hazards for the environment as, e.g., the sticking of valves may lead to dangerous chemical leaks. It is possible to reduce wear by using materials and coatings specially designed for the application. Such materials are often based on composite or nanocomposite concepts that typically incorporate ceramic additions to a metal matrix, but may also be based on other novel coating concepts. This paper presents trends in the development of hybrid materials and their use in components with novel functionality produced by thermal spraying and other compacting techniques.

The magnetostrictive materials exhibit a strain caused by the orientation of the magnetic moment when exposed to a magnetic field. A particular class of magnetostrictive materials is called magnetic shape memory (MSM) alloys or ferromagnetic shape memory alloy (FSMA) materials, which can change their shape remarkably when subjected to magnetic field. In the following, the MSM materials are introduced and their extraordinary structure, properties, and performance are described.

Abrasive wear is the most common type of wear phenomenon in mineral crushing industry. Tool steel matrix-based composites are an attractive choice to combat wear in those conditions because of their excellent abrasion resistance. One purpose of this study is to evaluate the abrasion resistance of such composites having different microstructures. Another purpose is to find out whether the simple dry sand rubber wheel abrasion test (ASTM G 65-91), which is a commonly used and relatively cheap and easy-to-perform test, could be used to rank materials for rock crushing although abrasive wear is not the only type of wear in the real rock crushing conditions. For this purpose Nordberg laboratory cone crusher test was used. Seven different composites were studied. The tool steel of type Ralloy®WR6 was used as a matrix material in all composites. The reinforcement was either cemented carbide (WC–Co), cast tungsten carbide (WC) or titanium carbide (TiC). The composites were manufactured by hot isostatic pressing (HIP).Abrasive wear properties of all the studied composites are very good. The reinforcement type, size, properties, volume fraction and reinforcement distribution in the matrix all influenced the wear results in both of the tests, but in a different way. Best wear resistance in cone crusher conditions was obtained with cemented carbide (WC–10Co) reinforced Ralloy®WR6 and in dry sand abrasion with WC reinforced Ralloy®WR6. No simple correlations between the dry sand rubber wheel abrasion test results and the cone crusher test results were found. This can be attributed to the different wear mechanics and consequently wear mechanisms in the two tests. In the dry sand rubber wheel abrasion test abrasion and detachment of the reinforcements are the major wear mechanisms while in the cone crusher abrasion with rock sliding and pure indentation are the major wear mechanisms. The differences in wear mechanisms result from differences in abrasives (type, size and hardness) and other wear conditions. It is concluded that dry sand rubber wheel abrasion test should not be used for screening materials for rock crushing applications as far as metal matrix composites are concerned.

Ion implantation has been shown to possess potential as a practical method for improving the mechanical properties of surfaces. So far a number of tests have been performed. In these studies, metals - most often steels or other hard materials - have been used. However, the improvement of the mechanical properties at the surface is not only important for substances that already have considerable hardness, but also for materials with other unique properties. Graphite is useful in many applications. Mechanically, it is easily machined and has good dimensional stability. It has self lubricity and under certain conditions has excellent sliding properties. Chemically, it is generally impermeable, resistant to corrosion, and compatable with mating materials. It is a good conductor of both heat and electrical current. The ion implantation of graphite has been studied elsewhere but without reference to the mechanical properties of the surface. It is expected, however, that heavy ion bombardment will cause structural changes at the graphite surface resulting in a modification of the mechanical properties. In this investigation the authors focus on these properties. The main objectives have been to study how the surface mechanical properties are changed by an ion bombardment and to find the relationshipmore » between mechanical properties and microstructure.« less

In this paper results of relaxation experiments on polycrystalline commercial purity copper are presented. Repeated load relaxation tests were performed by using a screwdriven testing machine. The results of the repeated load relaxation tests show that the stress-strain rate relation of the initial load relaxation cannot be reproduced by the repeated relaxations and that the structural changes that occur are time dependent. The direction of the change in the stress-strain rate relation with time suggests that the microscopic processes responsible for the observed time-dependence of relaxation behavior are related to reduced dislocation mobility or mobile dislocation density at low strain rates. By using a well-established phenomenological flow relation for the high-strain rate relaxation data and extrapolating it to low strain rates the time-dependent hardening process at low strain rates is found to have kinetics similar to those usually found in strain aging processes.