Technique for accelerated tests of samples for wear resistance

A review of the existing methods of accelerated abrasive wear tests is presented. The shortcomings of the technique implemented on an IM-01 installation of the VISKHOM design, as well as the Brinell-Howarth technique for laboratory studies, in which a powder abrasive is used are discussed, e.g., a problem of a uniform distribution of a free-flowing abrasive material over the surface of the contact zone, as well as problems of ensuring the stability of the supply of the abrasive material during the experiment. The goal of the study is to develop a methodology for comparative assessment of the wear resistance, excluding noted shortcomings. The tests were carried out on an M-1 installation using plate specimens 60 × 40 × 3 mm. The abrasive material used was a radial flap wheel 150 – 220 mm in diameter (width 30 mm, bore diameter 30 – 40 mm). The degree of wear was determined by a decrease in the mass of the sample by weighing on a balance with an accuracy of 0.1 mg before and after testing. The test results were considered as a relative wear resistance ε equal to the ratio of the wear resistance of the test specimen to the wear resistance of the reference one. The use of relative wear resistance makes it possible to increase the accuracy of the results obtained due to elimination of the influence of natural changes in external parameters that determine the intensity of wear during the test. The developed installation provides significant shortening of the accelerated comparative test (8 min) compared to 40 min on an IM-1, the structure and grain size of the working fluid, the constancy of the load in the contact zone and the speed of interaction between the sample and the tool being the same. Flap wheels of various grain sizes provide application of the device to a wide range of tasks without preliminary grinding of the samples and necessitate only their preliminary cleaning from slags and large particles after applying wear-resistant coatings.

1. Novikov V. S. Ensuring the durability of the working bodies of soil cultivating machines: monograph. — Moscow: INFRA-M, 2019. — 155 p. [in Russian].

2. Novikov V. S. Strengthening of the working bodies of tillage machines for a given resource: Monograph. — Moscow: NITs INFRA-M, 2018. — 169 p. [in Russian].

3. Kuzmenko A. G., Vishnevsky O. A. Brinell – Howarth (Br–Hv) abrasive wear test method. Part I. Theoretical foundations of the method. — Khmelnitsky: Khmelnitsky National University, 2012. P. 102 – 108 [in Russian].

4. Li C. X. Surface Engineering / Wear Testing and Wear Measurement. — The University of Birmingham, UK. http://emrtk. unimiskolc.hu/projektek/adveng/home/kurzus/korsz_anyag- tech/1_konzultacio_elemei/wear_testing_measurement.htm

5. Kennedy D. M., Hashmi M. S. J. Methods of wear testing for advanced surface coatings and bulk materials / J. Mater. Proc. Technol. 1998. N 77. P. 246 – 253.

6. Aulov V. F., Rozhkov Yu. N., Ishkov A. V., Krivochurov N. T., Ivanaisky V. V., Novikov V. S. Comparative tests for wear resistance of 65G steel specimens and specimens coated with high-speed HFC-borating / Energy-efficient and resource-saving technologies and systems. — Saransk: Natsional’nyi issledovatel’skii Mordovskii universitet, 2017. P. 422 – 427 [in Russian].

7. Aulov V. F., Ivanaisky V. V., Ishkov A. V., et al. Obtaining wear-resistant composite coatings on steel 65G with high-frequency heating / Tekhnol. Mashinostr. 2015. N 2. P. 30 – 34 [in Russian].

8. Aulov V. F., Ivanaisky V. V., Ishkov A. V., Koval D. V., Krivochurov N. T., Sokolov A. V. Obtaining wear-resistant composite boride coatings on steel 65g with TV-heating / Tekhnol. Mashinostr. 2015. N 2. P. 30 – 34 [in Russian].

9. Ishkov A. V., Lyalakin V. P., Aulov V. F., Krivochurov N. T., Ivanaisky V. V., Sokolov A. V. Combined functional coatings for parts of agricultural machinery of complex shape: design and production technology / Agricultural science — agriculture collection of articles: in 3 books. — Barnaul: Altai. Gos. Agrar. Univ., 2015. P. 59 – 60 [in Russian].

10. Ishkov A. V., Ivanaisky V. V., Krivochurov N. T., Maksimov A. A., Mishustin N. M. Influence of the nature of borating agent, fluxes and activators on the characteristics of coatings obtained by high-speed borating of alloyed steels / Polzunov. Vestn. 2010. N. 3. P. 142 – 146 [in Russian].