The course is offered both as a 10 CFU/ECTS course, composed of two parts (Physics of nuclear materials + Nuclear techniques for the analysis of materials), and as two separate 5 CFU/ECTS courses (Physics of nuclear materials, and Nuclear techniques for the analysis of materials); each of the two 5 CFU/ECTS courses is self-consistent, and can be taken alone.

Both parts mainly concern the interaction of nuclear radiations (electromagnetic radiations, elementary particles, atoms and ions) with materials. The first part focuses on the modification of materials induced by exposure to radiation; such a knowledge is a required basis for the design of engineering components which operate under irradiation. The second part focuses on the exploitation of the interaction between irradiation and nuclei, or some nuclear properties, as a tool for the investigation of materials.

PHYSICS OF NUCLEAR MATERIALS (5 ECTS)

The objective of this course is twofold. Firstly, to give a comprehensive overview of the macroscopic properties of various types of materials exploited in nuclear systems, with a peculiar emphasis on the materials adopted in nuclear power plants, and of the phenomenological effects of irradiation on such properties. Secondly, to provide the knowledge of the microscopic mechanisms which allow to interpret the behavior of irradiated materials, and to understand the dependence of their evolution on parameters like the temperature. The main focus is on neutron irradiation of structural metals, as it happens in nuclear power plants.

NUCLEAR TECHNIQUES FOR THE ANALYSIS OF MATERIALS (5 ECTS)

The objective of the course is to provide the knowledge and the understanding of several techniques for the investigation of materials, with an emphasis on inorganic materials. The considered techniques are those which adopt probes such as neutrons, ions and high energy photons, and which exploit nuclear reactions, or nuclear properties, or instruments like accelerators, which have mainly been developed in the nuclear field. Electronic spectroscopy techniques are considered in other courses, and will not be treated here; where appropriate, comparisons with electronic spectroscopies will be proposed.

The focus will be on the physical principles of operation of each technique, which are the basis for assessing their potentialities and their limitations, and to compare their possible performances.

In order to offer a self-consistent course, also to students having different backgrounds, a few topics of physics, having a broader scope, will be briefly reviewed: collisions, nuclear reactions, multipole expansion of electromagnetic fields, the behavior of magnetic dipoles in magnetic fields.

PHYSICS OF NUCLEAR MATERIALS (5 ECTS)

The student knows and understands the main duties to be performed in nuclear systems, the properties and the performances required to the different materials in order to face such duties, the evolution of the properties of different materials induced by irradiation, the dependence of these evolutions on the irradiation conditions.

The student also knows and understands the main microscopic mechanisms activated by irradiation which determine the above mentioned evolution, and their dependence on physical parameters.

The student is able to evaluate the burden posed to materials by different types of irradiation fields, to assess the suitability of different materials for various functions to be accomplished in nuclear systems, to make a critical choice of materials, and a preliminary assessment of their possible performances.

NUCLEAR TECHNIQUES FOR THE ANALYSIS OF MATERIALS (5 ECTS)

The student knows and understands the operational principles of various investigation techniques, based on nuclear reactions, or on nuclear probes, or on nuclear properties, and the type of information that can be gained from each of them.

The student is able to make a critical choice of the technique(s) which are most appropriate to answer a given investigation need.

The student is able to assess the scientific literature which presents the outcome of the application of different techniques.

PHYSICS OF NUCLEAR MATERIALS

The treatment of some topics will be differentiated according to the different backgrounds of the students.

Topic 1: Reminders of solid state physics and of physical metallurgy (this topic will be almost skipped by the students whose background includes materials science topics (see Topic 3); it will instead be treated in an introductory way for the students who lack such a background).

• Defects in crystals: vacancies, interstitials, dislocations, grain boundaries;
• Diffusion and self-diffusion in solids;
• Plastic deformation and creep: characters, interpretation by micromechanisms (dislocation glide, dislocation climb, interaction with point defects, diffusion of point defects).

Topic 2: Irradiation.

• Reminders about collision phenomena, elastic and inelastic;
• Neutron irradiation: nuclear reactions, scattering; irradiation by charged particles (electrons, ions): basic concepts;
• Irradiation by fast neutrons: primary knocked atom, collisional cascades; the 'displacement per atom' (dpa) concept, its evaluation;
• Focusing and channeling phenomena.

Topic 3: Simulation of radiation damage by Montecarlo codes like SRIM (this topic will be barely introduced for all the students, and developed more extensively, including applicative exercises, for the students who, having a materials science background, can almost skip Topic 1).

Topic 4: Evolution of the microstructure of irradiated metals.

• Mobility of point defects, depending on temperature; the evolution of a defect population: annihilation, aggregation (dislocation loops, voids, bubbles), interaction with sinks, irradiation enhanced diffusion;
• Macroscopic effects: irradiation enhanced creep, irradiation induced creep, swelling, growth, embrittlement, enhanced segregation.

Topic 5: Basic properties of ceramic nuclear fuels.

• Uranium and plutonium dioxides: properties, effects of temperature (sinterization) and of thermal gradients (restructuring). Other ceramic fuels.

Topic 6: Chemical phenomena in reactors 

• Corrosion mechanisms in presence of water; the corrosion of zirconium in water reactors;
• Corrosion of steels in lead reactors;
• Water radiolysis in water reactors: the countermeasures, the treatments of 'water chemistry'.

Topic 7: Superconductors in nuclear systems.

• Basic phenomena concerning superconductivity; critical temperature, critical current, critical magnetic field. Exploitation of superconductivity to build magnets;
• ‘Conventional’ superconductors: NbTi and Nb₃Sn; hints to High T_c superconductors;
• Optional, for the students who have an appropriate background: introduction to the microscopic theory of superconductivity.

 NUCLEAR TECHNIQUES FOR THE ANALYSIS OF MATERIALS

Students who are in the nuclear engineering curriculum obviously have a background on the physics of nuclei. The course is also offered to students who are not in this curriculum, and who lack this type of background. Those students will be offered an overview of the fundamental topics about the structure and properties of nuclei, radioactive decays and nuclear reactions. This overview, which is not strictly part of the course, is offered them as a pre-requisite which enables them to fruitfully attend the course.

Topic 1: Recollection of topics of general physics, needed for the analysis of one or more techniques.

• Collisions;
• multipole expansion of electromagnetic fields; interaction among multipoles and electromagnetic fields;
• magnetic dipoles in a magnetic field;
• X ray emission: continuous and discrete spectra;
• Interaction of X rays and gamma rays with matter: scattering, absorption.

Topic 2: Techniques which exploit and detect high energy photons:

• X ray fluorescence (XRF);
• Mössbauer spectroscopy.

Topic 3: Techniques which exploit accelerated light nuclei.

• Rutherford backscattering analysis (RBS);
• Elastic recoil detection analysis (ERDA);
• Particle-Induced X-ray Emission (PIXE);
• Particle-Induced gamma-ray Emission (PIGE);
• Ion Beam Analysis (IBA);
• Secondary ions mass spectroscopy (SIMS).

Topic 4: Techniques which exploit neutrons.

• Neutron Activation Analysis (NAA);
• Nuclear reaction analysis (NRA);
• Neutron diffraction techniques (X ray diffraction (XRD) is treated in other courses; focus is on the peculiarities of neutron diffraction, in comparison with XRD);
• Inelastic neutron scattering.

Topic 5: Techniques which exploit the properties of nuclei.

• Nuclear magnetic resonance (NMR); analogies with the electron spin resonancs (ESR, or EPR) technique.

For all the techniques the focus is more on the basic principles of their operation, than on many technical details of their implementations.

For the students of the nuclear engineering curriculum the level of knowledge required for the admission to the Master of Science in Nuclear Engineering, or gained within the first semester of the curriculum, is sufficient for the full understanding of the topics taught in the course. More specifically, the part on Nuclear techniques assumes a besic knowledge of the quantum mechanical description of atoms. The part on Nuclear materials needs some topics of physical metallurgy: since some students of the Nuclear Engineering curriculum lack these subjects, for them all the needed topics will be presented within the course.

The course on Nuclear techniques for the analysis of materials is also offered to students of other curricula. Most of these students lack the basic subjects about the structure and properties of nuclei, radioactive decays and nuclear reactions; for them, all the needed topics will be presented, during the first part of the course, in a small set of additional lectures.

PHYSICS OF NUCLEAR MATERIALS

The assessment is performed by an oral examination, which tests the knowledge and understanding of the various phenomena occurring in irradiated materials, and of their relevance towards the ability of manufactured components to fulfill their duties.

The ability to identify the selection criteria, by which selecting the appropriate materials to face technological requirements, is also assessed in the same oral examination.

NUCLEAR TECHNIQUES FOR THE ANALYSIS OF MATERIALS

The assessment is performed by an oral examination, which tests the knowledge and understanding of the physical principles underlying the various techniques, and of the type of information which can be gained by the same techniques.

The ability of selecting the most appropriate technique to investigate a specific aspect is also assessed, as well as the ability of understanding and interpreting the specific scientific literature.

Old text, still very useful. Retrievable only as .pdf file

This is a broad treatise, containing also several detailed treatments which are not required for this course. Due to the huge number of misprints, the book can be used only together with the errata.

excerpts of other books, made available on the BeeP site of the course

Covers several nuclear techniques. - Available as E-book at Politecnico library.

Available as E-book at Politecnico library

Only for some techniques. A level of detail far beyond the one needed for the course. Available as E-book at Politecnico library.

Only for neutron techniques. A level of detail far beyond the one needed for the course. Available as E-book at politecnico library.

Only for the description of spin in a magnetic field.