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ArticleName Perspectives and problems of modern depth-sensing indentation techniques application for diagnostics of coals mechanical properties
DOI 10.17580/gzh.2017.12.05
ArticleAuthor Kossovich E. L., Epshtein S. A., Shkuratnik V. L., Minin M. G.

National University of Science and Technology ‘MISIS’, Moscow, Russian Federation:

E. L Kossovich, senior researcher, scientific-educational laboratory of physics and chemistry of coals, Candidate of Physico-mathematical Sciences,
S. A. Epshtein, Head of scientific-educational laboratory of physics and chemistry of coals, Doctor of Engineering Sciences
V. L. Shkuratnik, Professor, Doctor of Engineering Sciences


Federal State Autonomous Educational Institution of Higher Education «Ural Federal University named after the first President of Russia B. N. Yeltsin»:
M. G. Minin, Assistant of the Department of Physical Methods and Quality Control Instruments of the Physics and Technology Institute


Modern methods of depth-sensing indentation could be a source of essential information on coals mechanical properties at different scales in order to characterize local properties of individual microcomponents as well as their complexes. Such methods allow characterization of coals structural components response at external loading, their ability or inability to be restored after unloading. Automatically driven grid measurements made at specifi c area of sample allow mapping of elastic moduli and hardness to study inhomogeneity of coals microcomponents and their complexes, etc. A number of methodical problems related to using of depth-sensing indentation for coals mechanical properties characterization are analyzed. These include complications at fulfilment of special requirements for samples preparation and conditions of experiments. The necessity was pointed out for development of new approaches for interpreting of experimental results obtained at different scales. Solution of the methodic problems analyzed in the work will allow deriving of adequate information on coals mechanical properties. Such information is needed for prognosis of coals dust and gas outbursts, coal products quality loss evaluation at transportation and storage, studying of factors influencing concentration and size of coals dust formed at coals mining and processing, etc.
The work was financially supported by the Russian Science Foundation (grant # 16-17-10217).

keywords Coal, mechanical properties, hardness, elastic modulus, nanoindentation, microindentation

1. Zhu Q. Coal sampling and analysis standards. IEA Clean Coal Centre. 2014. 123 p.
2. Gonzatti C., Celestino T. B., Bortolucci A. A. Determination of in situ uniaxial compressive strength of coal seams based on geophysical data. Bulletin of Engineering Geology and the Environment. 2009. Vol. 68. No. 1. pp. 65–80.
3. Pan J., Meng Z., Hou Q., Ju Y., Cao Y. Coal strength and Young’s modulus related to coal rank, compressional velocity and maceral composition. Journal of Structural Geology. 2013. Vol. 54. pp. 129–135.
4. West R. D., Markevicius G., Malhotra V. M., Hofer S. Variations in the mechanical behavior of Illinois bituminous coals. Fuel. 2012. Vol. 98. pp. 213–217.
5. Gao F., Kang H. Experimental Study on the Residual Strength of Coal Under Low Confinement. Rock Mechanics and Rock Engineering. 2017. Vol. 50. No. 2. pp. 285–296.
6. Khruschchov M. M., Berkovich E. S. Microhardness determined by indentation. Moscow-Leningrad: USSR Academy of Sciences Publisher. 1943. 69 p.
7. Eremin I. V., Babashkin B. G., Gagarin S. G., Korolev Y. M. Division of coals on the fragility and placticity. Coke and Chemistry. 2000. No. 2. pp. 7–13.
8. Musyal S. A. Microhardness and microbrittleness as possible parameters for classification of fossil coals. Petrographic Specific and Properties of Coals. Ed. I. I. Amnosov. Moscow : USSR Academy of Sciences Publisher. 1963. pp. 164–188.
9. GOST 21206–75. Coals and anthracite. Determination method for microhardness and microbrittleness. Moscow : IPK Izdatelstvo standartov, 2000.
10. Kalei G. N. Some results of microhardness test using the depth of impression. Mashinovedenie. 1968. Vol. 4. No. 3. pp. 105–107.
11. Bulychev S. I., Alekhin V. P., Shorshorov M. K., Ternovskij A. P., Shnyrev G. D. Determination of Young modulus by the hardness indentation diagram. Zavodskaya Laboratoriya. 1975. Vol. 41. No. 9. pp. 1137–1140.
12. Wang X., Peng X., Guo Z. An experimental study of the indentation behaviour of Al foam. Engineering Review. 2014. Vol. 34. No. 1. pp. 15–21.
13. Bull S. J. Nanoindentation of coatings. Journal of Physics D: Applied Physics. 2005. Vol. 38. No. 24. pp. R393–R413.
14. Zhu W., Hughes J. J., Bicanic N., Pearce C. J. Nanoindentation mapping of mechanical properties of cement paste and natural rocks. Materials Characterization. 2007. Vol. 58. No. 11-12. pp. 1189– 1198.
15. Palacio M. L. B., Bhushan B. Depth-sensing indentation of nanomaterials and nanostructures. Materials Characterization. 2013. Vol. 78. pp. 1–20.
16. Kossovich E. L., Dobryakova N. N., Epshtein S. A., Belov D. S. Mechanical properties of coal microcomponents under continuous indentation. Journal of Mining Science. 2016. Vol. 52. No 5. pp. 906–912.
17. Epshtein S. A., Borodich F. M., Bull S. J. Evaluation of elastic modulus and hardness of highly inhomogeneous materials by nanoindentation. Applied Physics A: Materials Science and Processing. 2015. Vol. 119. No. 1. pp. 325–335.
18. Manjunath G.L., Nair R.R. Implications of the 3D micro scale coal characteristics along with Raman stress mapping of the scratch tracks. International Journal of Coal Geology. 2015. Vol. 141–142. pp. 13–22.
19. Kožušníková A. Determination of Microhardness and Elastic Modulus of Coal Components by Using Indentation Method. GeoLines. 2009. Vol. 22. pp. 40–43.
20. Oliver C., Pharr M. An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. Journal of Materials Research. 1992. Vol. 7. No. 11. pp. 1564–1583.
21. Johnson K. L., Kendall K., Roberts A. D. Surface Energy and the Contact of Elastic Solids. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 1971. Vol. 324. No. 1558. pp. 301–313.
22. Liu X., Dai F., Zhang R., Liu J. Static and dynamic uniaxial compression tests on coal rock considering the bedding directivity. Environmental Earth Sciences. 2015. Vol. 73. No 10. pp. 5933–5949.
23. Szabo T. L. A representative poisson’s ratio for coal. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts. 1981. Vol. 18. No. 6. pp. 531–533.
24. Argatov I. I., Borodich F. M., Epshtein S. A., Kossovich E. L. Contact stiffness depth-sensing indentation: Understanding of material properties of thin films attached to substrates. Mechanics of Materials. 2017. Vol. 114. pp. 172–179.
25. Kossovich E. L., Borodich F. M., Bull S. J., Epshtein S. A. Substrate effects and evaluation of elastic moduli of components of inhomogeneous films by nanoindentation. Thin Solid Films. 2016. Vol. 619. pp. 112–119.

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