L.N. Gumilyov Eurasian National University, a dissertation defense for the degree of Doctor of Philosophy (PhD) by Zhomartova Ayazhan Zhomartkyzy on the topic «Structural features of ceramic and metal objects of cultural heritage: studies by neutron tomography and diffraction» in the educational program «8D05305 – Nuclear physics».
The dissertation was carried out at the «Nuclear physics, new materials and technologies education department» of L.N. Gumilyov Eurasian National University.
The language of defense is russian
Official reviewers:
Ismailov Daniyar Valerievich – Candidate of Technical Sciences, Associate Professor, Head of the Laboratory of Radiation Physics and Functional Materials, FTF, KazNU named after Al-Farabi, (Almaty, Republic of Kazakhstan);
Ahmedov Gadir Sattar oglu – Doctor of Physical Sciences, Senior Researcher of the Department of Nuclear Research, Agency for Innovation and Digital Development, (Baku, Republic of Azerbaijan).
Temporary members of the Dissertation Council:
Mirzayev Matlab Nabi – Doctor of Physical and Mathematical Sciences, Senior Researcher at the Institute of Radiation Problems, Ministry of Science and Education Azerbaijan, (Baku, Republic of Azerbaijan);
Nurbakova Guliya Serikmukhametovna – Candidate of Physical and Mathematical Sciences, Associate Professor of the Department of Theoretical and Nuclear Physics, KazNU named after Al-Farabi, (Almaty, Republic of Kazakhstan);
Belozerova Nadezhda Makhmudovna – Candidate of Physical and Mathematical Sciences, Senior Researcher at the Center for Photonics and Two-Dimensional Materials, Moscow Institute of Physics and Technology, (Moscow, Russian Federation).
Scientific consultants:
Daniyar Maralovich Janseitov – Doctor of Philosophy (PhD), Leading Researcher at the RSE at the Institute of Nuclear Physics (specialty "6D060500 – Nuclear Physics") (Almaty, Republic of Kazakhstan);
Sergey Evgenievich Kichanov – Doctor of Technical Sciences, Head of Group of the I.M. Frank Laboratory of Neutron Physics at the Joint Institute for Nuclear Research (Dubna, Russian Federation).
The defense will take place on May 16, 2025, at 02:00 PM in the Dissertation Council for the training direction «8D053 – Physical and chemical sciences» in the educational program «8D05305 – Nuclear physics» of L.N. Gumilyov Eurasian National University. Conducting a meeting of the dissertation council in a mixed (offline and online) format.
Link: https://clck.ru/3L2F5T
Address: Astana, Satpayev St. 2, room 302.
Abstract (English): the dissertation work of Zhomartova Ayazhan Zhomartkyzy on the topic “Structural features of ceramic and metal objects of cultural heritage: research by neutron tomography and diffraction methods”, submitted for the degree of Doctor of Philosophy (PhD) in the educational program: 8D05305 – “Nuclear Physics” Relevance of the research topic. Progress in modern applied nuclear physics is inextricably linked with the development of methods for studying new materials, which are complex multicomponent systems and have certain structural features or physical properties that have multidisciplinary value. Nuclear physical studies of the structural features of materials and comparison of the obtained data with certain technological features or physical and chemical aspects of their production allows researchers to obtain reliable and consistent information about the dominant structural mechanisms for the formation of the properties of these objects or to group a number of materials according to certain structural similarity criteria. One of the modern nuclear physical methods for studying the structural features of materials at the micron level with characteristic sizes of the objects under study from tens of microns to several centimeters is the method of neutron radiography and tomography [1–3]. This method consists of obtaining neutron images of the objects under study: due to different degrees of attenuation of the intensity of the neutron beam when passing through components of different chemical compositions [2], density and thickness of the sample under study, it is possible to obtain information about the internal structure of the materials under study with spatial resolution at the micron level [4]. This method of non-destructive testing is characterized by deeper penetration into the thickness of the material under study compared to the complementary method of X-ray radiography and has advantages when studying objects that simultaneously contain both light elements (for example, hydrogen or lithium) and heavy ones [2,5]. The neutron radiography method is currently widely used in the study of materials and products for nuclear technologies [6], paleontological and geophysical objects [7,8], giving a complete picture of internal inhomogeneities, cracks and pores inside the material [9], the spatial distribution of various elements and phase components, hidden defects and structural elements [10]. And here it should be noted that one of the important areas in applied research using neutron radiography and tomography is the study of cultural heritage objects [4,11]. On the one hand, archaeological material stores valuable information about the trade, economic and social development of ancient civilizations and states [12], and on the other hand, such materials are convenient model objects for studying the processes of corrosion and cracking, multicomponent phase space [13], and geometry structural elements [14–16]. And in this case, the development and implementation of new methods, or the optimization and development of existing techniques and algorithms for the structural analysis of complex multi-component archaeological materials based on neutron radiography and tomography data, is relevant. Objects of research. A number of archaeological materials were selected as research objects, which are model objects for nuclear physics and archaeological scientific fields: Byzantine ceramics from excavations in Dobrudja (Romania), ceramics of ancient Turkic and Saka tribes on the territory of modern Kazakhstan, brass ingots from the archaeological complex of Sherbet ( Tatarstan, Russia) and metal objects of cultural heritage of Kazakhstan from the Eleke Sazy complex. Subject of study. The subject of the research is the structural features and spatial inhomogeneities inside ceramic and metal materials, as well as the development of the experimental and methodological base of the neutron radiography and tomography method for their study and analysis. The purpose of the dissertation work is the comprehensive application of the non-destructive structural method of neutron radiography and tomography to the study of ceramic and metal objects of cultural heritage, analysis of tomographic data to identify the structural features of these objects for their systematic grouping, comparison of structural data with the technological features of ancient pottery and foundries. Application of optimization and adaptation of methods, as well as algorithms for calculating the structural factors of ceramic and metal objects of neutron tomography, neutron diffraction. Research objectives. To achieve the goal of the dissertation work, specific tasks are required: 1. Study of the phase composition, spatial distribution of phases and structural inhomogeneities in ceramic fragments of ancient Byzantium from excavations in Dobruja (Romania) using neutron diffraction, neutron tomography and Raman spectroscopy methods. 2. Grouping of ceramic samples from excavations in Dobruja (Romania) based on the obtained neutron radiography and tomography data. 3. Structural studies of ceramic fragments from pottery workshops of ancient tribes living on the territory of modern Kazakhstan using neutron diffraction and tomography methods, Raman spectroscopy. Identification of the dominant structural features to characterize the specifics of pottery production of ancient tribes living on the territory of modern Kazakhstan. 4. Study of the structural organization of massive bronze objects from the archaeological complex of Eleke Sazy, Republic of Kazakhstan using neutron tomography. Identification of structural features and parameters of the constituent components of the objects under study. 5. Study of the spatial distribution of phase components in brass ingots from the Shcherbet archaeological complex (Tatarstan, Russia) using the neutron tomography method. Research methods. Neutron methods of structural diagnostics are non-destructive methods; they provide detailed information about the internal structure and composition of the artifacts under study, without causing any mechanical or other damage [13,16,17]. This is crucial for the study of cultural heritage sites, which are often unique. The goals and objectives of the dissertation work are achieved by using not one, but a whole complex of nuclear physical research methods, which provides comprehensive information about the internal structure and structural features of the studied cultural heritage objects using non-destructive testing methods. For the experimental implementation of identifying the structural features of archaeological materials with characteristic sizes of the studied objects from 50 microns, the method of neutron radiography and tomography was used [1,18]. This non-destructive testing method is characterized by deeper penetration into the thickness of the material under study compared to the complementary X-ray radiography method and has advantages when studying objects that simultaneously contain both light elements (for example, hydrogen or lithium) and heavy elements. Neutron radiography and tomography studies were carried out at a specialized station for research using neutron radiography and tomography [19,20] at the IBR-2 reactor (Dubna, Russia) and at the TITAN neutron radiography station [21,22] at the VVR-K reactor ( Almaty, Kazakhstan). In addition to the method of neutron radiography and tomography, in obtaining the results presented in the dissertation, complementary methods of structural diagnostics were used: the method of neutron diffraction and Raman spectroscopy. A reliable experimental method for obtaining information about the crystal structure of materials is the neutron diffraction method [23,24]. This method makes it possible to study the structure of crystals containing light atoms or elements with similar atomic numbers, which in many cases (especially in systems with disordering of light atoms: hydrogen or oxygen) is difficult to do using X-ray diffraction. Also an important factor is the high penetrating ability of neutrons. Neutron diffraction experiments were carried out on specialized neutron diffractometers for studying microsamples DN-6 [25] and DN-12 [26,27] at the high-flux pulsed reactor IBR-2. Complementary to the methods of structural diagnostics is one of the methods for studying the vibrational spectra of atoms - the method of Raman scattering or Raman spectroscopy [28,29]. The development of laser technology and recording systems makes it possible to obtain data on the phase composition of materials from their surface, which is important additional information for structural neutron diagnostics of the materials under study. The study of the microstructural and morphological characteristics of antique ceramics was complemented by the use of complementary methods, such as electron and optical microscopy, neutron activation analysis using prompt gamma rays PGAA, as well as X-ray fluorescence analysis. A complementary approach to studying the characteristics of archaeological materials allows us to obtain reliable and consistent information about the technological aspect of the ancient production of these materials at the micron structural level: the distribution of mineral and phase components in volume, the geometry of internal heterogeneities, the morphology of the constituent components, etc. Main provisions submitted for defense: 1. The high neutron radiographic contrast between the mineral phase components in ceramic samples from mounds No. 7 and No. 20 of the Eleke Sazy complex reliably separates the volume fractions of quartz and feldspar minerals. Data on fractional volume ratios and the reconstructed spatial distribution of the main minerals in ceramic samples. The high penetrating power of neutrons revealed the porosity of ceramic archaeological materials from the Eleke Sazy and Asusay complex in the range of 0.75 – 1%. 2. Determination of the annealing temperature of ceramic materials based on the displacement of the characteristic frequency of graphite in Raman spectroscopy experiments. The temperature values in the range from 850 °C to 1000 °C correspond to objects of the Early Iron Age and the Middle Ages, up to 800 °C for ceramic fragments of the Bronze Age. 3. Results of statistical cluster analysis based on structural neutron diffraction data for Byzantine ceramics (Dobrudja district, Romania). The separation of the studied ceramic materials into four groups depending on the fractional contents of the mineral phase components. 4. Determination of the volume fraction of brass and Cu2O cuprite in ingots of the Sherbet archaeological complex (Russia) from experimental neutron tomography data. The cuprite Cu2O content ranges from 0.5 to 6.6%. Determination of the zinc content by changing the parameters of the unit cell of the copper phase according to neutron diffraction data. Scientific novelty of the work. All scientific results presented in the dissertation were obtained for the first time. The uniqueness of the archaeological objects under study, the capabilities of the method of neutron radiography and tomography, and an integrated approach to scientific research determine the scientific novelty of the methodological and scientific results of the dissertation. The use of the method of neutron radiography and tomography, an integrated approach to research, as well as the use of modern algorithms for analyzing experimental data makes it possible to determine the historical prerequisites for the technological development of ancient communities, to identify the dominant structural factors at the micron level of the structural organization of objects for the development of new historical concepts. Among the more specific aspects of novelty presented in the dissertation work: 1. Data on the spatial distribution of heterogeneities within all studied archaeological sites, obtaining and analyzing three-dimensional models of rare cultural heritage objects were obtained for the first time. 2. For the first time, the phase composition of ceramic material from the archaeological complex of Sabyrbay, Ainabulak, Eleke Sazy, Zhaipak, Asusai (Kazakhstan) and Dobruja (Romania) was studied. 3. For the first time, results have been obtained on the spatial distribution of the main mineral phases in ceramic materials from the archaeological complex of Sabyrbay, Ainabulak, Eleke Sazy, Zhaipak, Asusay (Kazakhstan) and Dobruja (Romania). 4. For the first time, a grouping of ceramic material from the archaeological complex of Dobruja (Romania) was carried out based on neutron tomography and diffraction data. 5. For the first time, the features of temperature annealing of ceramic material from the archaeological complex of Sabyrbay, Ainabulak, Eleke Sazy, Zhaipak (Kazakhstan) were studied using Raman spectroscopy data. 6. For the first time, the features of the spatial distribution of metal and corrosion products in foundry blanks from the Shcherbet archaeological complex (Tatarstan, Russia) were studied. 7. For the first time, volume fractions of corrosive products and metal were calculated from neutron tomography data. 8. For the first time, three-dimensional models of metal archaeological objects of the Eleke Sazy complex (Kazakhstan) were obtained. Scientific and practical value of the work. The method of neutron radiography and tomography, as a representative of the family of non-destructive testing methods, has become widespread in applied scientific research of technological and engineering objects; in paleontology and geophysics; studying sources of electric current and batteries; processes associated with the penetration of water into the thickness of various materials, non-destructive research of rare and unique cultural heritage objects. Taking into account the high applied value of the method of neutron radiography and tomography, work is currently underway in all the world's leading neutron centers to create and develop experimental methods of neutron radiography and tomography. The development, adaptation and application of methods and algorithms for primary processing of neutron radiography and tomography data, reconstruction of three-dimensional models from neutron tomography data, analysis of three-dimensional data are universal tools and can be used at other neutron radiography and tomography facilities. It should be noted that the experimental data obtained are important for the development of methodology for the restoration and preservation of valuable archaeological finds, and are also invaluable material in identifying the authenticity and authenticity of especially valuable artifacts. Non-destructive structural diagnostics of rare natural heritage objects and algorithms for the analysis of two-dimensional and three-dimensional data can be applied in other structural tomographic studies. The results of the study of cultural heritage objects using the neutron tomography method are the documentary basis for the inclusion of neutron radiography and tomography methods in the general protocol for research and diagnosis of archaeological materials. Based on the information received about the internal structure of cultural heritage objects, the structure of hidden nodes or fasteners, and the spatial distribution of various phases, archaeologists and historians propose concepts and models of cultural-historical or manufacturing sources of a particular cultural heritage object. The results of the study of cultural heritage objects served as the basis for the inclusion of neutron radiography and tomography methods in the general protocol for research and diagnosis of archaeological materials. Personal contribution of the author. Of the author's personal contribution, it should be noted the identification of research directions, formulation of scientific problems, their experimental implementation, processing, analysis and generalization of the results obtained. The author independently obtained and analyzed neutron data from the study of all objects under study using neutron radiography and tomography. The defining contribution of the author of the dissertation in adapting for neutron radiographic data is a set of software tools for processing and analyzing neutron radiographic images, tomography reconstruction algorithms, and three-dimensional data analysis algorithms. The author prepared most of the publications of the dissertation independently, starting from data analysis and ending with preparing the text of articles. Of the works performed in co-authorship, the dissertation includes the results obtained with the decisive participation of the author in setting problems, developing methods for solving them, and analyzing experimental data. The main provisions submitted for defense reflect the author’s personal contribution to the published works. Reliability of work results. The degree of reliability of the results is confirmed by the correct formulation of the problem and a reasonable choice of research methods, regular quality control of analytical procedures, and the convergence of results obtained by alternative or complementary methods of structural diagnostics. The experimental data obtained were analyzed and compared with the known experimental results of other researchers. All results included in the dissertation work were published in peer-reviewed journals and were tested at international and national conferences and were published in peer-reviewed journals. Approbation of work. The main results of the work were reported and discussed at 9 international and national scientific schools and conferences: 1. First International Scientific School-Conference “Atom. The science. Technologies" (April 14-16, 2021, Almaty, Kazakhstan); 2. Conference on the use of neutron scattering in condensed matter RNIKS-2021 (September 27-October 1, 2021, Yekaterinburg, Russia); 3. Second international workshop “Application of nuclear physics methods for the study of cultural heritage objects” (October 16-20, 2021, Kazan, Russia); 4. TIM20-21 Physics Conference (November 11-13, 2021, Timisoara, Romania); 5. International conference “Condensed Matter Research at the IBR-2 Reactor” (April 25-29, 2022, Dubna, Russia); 6. XI Annual Conference of Young Scientists and Specialists “Alushta-2022” (June 5-12, 2022, Alushta, Crimea); 7. 55th meeting of the PAC for Condensed Matter Physics (January 20-21, 2022, Dubna, Russia); 8. 57th meeting of the PAC for Condensed Matter Physics (June 15-16, 2023, Dubna, Russia); 9. 59th meeting of the PAC for Condensed Matter Physics (June 24-25, 2024, Dubna, Russia). Publications. Based on the results of the dissertation work, 9 works were published, of which 7 articles were published in publications with a non-zero impact factor included in the Scopus database; 2 articles – in collections of materials of international conferences. Structure and scope of the dissertation. The dissertation consists of an introduction, four chapters, a conclusion, and a list of sources used. The volume of the dissertation is 121 pages, contains 64 figures and 12 tables. The number of sources used is 209. In the Introduction, the relevance and novelty of the work is discussed, the scientific and practical value of the goals of the dissertation work is formulated and justified. The main provisions submitted for defense, the personal contribution of the author, publications, testing and a summary of the dissertation are given. The first chapter is devoted to a review and theoretical foundations of neutron radiography and tomography methods being developed and used for structural diagnostics at the micron level. The mathematical foundations of the neutron diffraction method using pulsed neutron sources are described. The main emphasis is on the structural aspects in the study of archaeological materials, and a detailed description of them is given. The second chapter is devoted to a detailed description of the experimental methods used in obtaining the results of this dissertation. A detailed description of the experimental neutron radiography and tomography stations at the VVR-K research reactor and the IBR-2 pulsed high-flux reactor is provided, as well as methodological techniques and algorithms for analyzing the quality of experimental neutron two-dimensional and three-dimensional data. A description is given of the neutron diffractometers DN-12 and DN-6, used for phase analysis of ceramic samples. In addition, a Raman spectrometer and a setup for performing PGAA used in the research of the dissertation work are described. The third chapter is devoted to the study of the internal structure of ceramic materials from different historical complexes using the method of neutron diffraction and tomography. The results of neutron tomography on the study of ceramic materials from the archaeological complex of Sabyrbay, Ainabulak, Eleke Sazy, Zhaipak, Asusai (Kazakhstan) and Dobruja (Romania) are presented. The phase composition of this ceramic material was studied by neutron diffraction and Raman spectroscopy. Particular attention is paid to the procedure for grouping ceramic materials according to the criteria of phase composition and size distribution of internal pores according to neutron tomography and diffraction methods. The fourth chapter is devoted to the analysis of the structural features of the spatial distribution of metal and corrosion products in foundry blanks from the archaeological complex of Sherbet (Tatarstan, Russia) and metal archaeological objects of the Eleke Sazy complex (Kazakhstan). The Conclusion formulates the main conclusions of the dissertation work. Bibliography [1] Strobl M, Manke I, Kardjilov N, Hilger A, Dawson M, Banhart J. Advances in neutron radiography and tomography. J Phys D Appl Phys 2009; 42. [2] Kardjilov N, Manke I, Hilger A, Strobl M, Banhart J. Neutron imaging in materials science. Materials Today 2011; 14:248–256. 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Conclusion of the Research Ethics Committee
Defense of the dissertation: https://www.youtube.com/watch?v=quoCWRP7k2o&ab_channel=ENUOFFICIAL
