DETERMINATION OF THE STRENGTH CHARACTERISTICS OF STEEL 15Kh2NMA BY THE INDENTATION METHOD

Authors

  • О. А. Каток instrumented indentation method, indentation curve, ultimate strength, tensile yield strength, Ukraine

DOI:

https://doi.org/10.20535/2305-9001.2014.71.35571

Keywords:

instrumented indentation method, indentation curve, ultimate strength, tensile yield strength

Abstract

Purpose. Experimental justification for the use of the instrumented indentation method in nuclear power engineering to assess the current state of structural materials for the purpose of determining their remaining life.

Design/methodology/approach. In addition to direct destructive methods for determining the strength characteristics, a great number of indirect methods of non-destructive testing are used in the industry. One of these methods is the instrumented indentation method that is based on the continuous recording of the local deformation process in the indenter material in the form of indentation diagrams in the force, F, vs. indenter penetration depth, h, (hereinafter, “the indentation depth”) coordinates. The advantage of the method, as compared to the hardness measurement methods, consists in the possibility of the direct recording of the process of continuous local deformation of the material by the indenter, in the simple and rapid testing due to the automation of the process itself and also in the absence of the effect of such human factor, as visual measurement of diagonal length of the indentation.

Findings. Using the improved procedures and the developed experimental equipment for testing metals by the indentation method, the experimental investigations of high-alloy steel Grade 15Kh2NMFA  in different as-supplied conditions have been performed. It has been shown that the spread of the results obtained to determine the strength characteristics of the steel under investigation from the data obtained in tensile testing does not exceed 5%. The obtained experimental data support the possibility of using the instrumented indentation method in nuclear power engineering as one of the non-destructive testing methods.

Originality/value. The procedures and equipment for testing with the use of the instrumented indentation method can be used to assess the current state of structural materials in operating engineering products for the purpose of determining the remaining life

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Published

2014-12-24

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