Jerzy Napiórkowski

Prof. Dr. Jerzy Napiórkowski

Department of Building and Exploitation of Vehicles and Machines, Faculty of Technical Sciences, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 July 2019 in Materials
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Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
Magdalena LemechaMagdalena Lemecha
Magdalena Lemecha
ŁKŁukasz Konat
Łukasz Konat
This paper presents the forecasting of the wear of working elements in an abrasive soil mass using the theoretical wear model. One of the widely used models providing a basis for the relationships describing wear is the Holm-Archard model. This relationship describes abrasive wear because of the contact between two bodies. The model assumes that the wear of an operating part is directly proportional to the sliding force and distance and inversely proportional to the hardness of the material of the part. To date, the model has not been verified in the wear of a soil mass, which is a discrete friction surface. Four grades of steel resistant to abrasive wear, intended for the manufacturing of operating parts exposed to wear within a soil mass, Hardox 500, XAR 600, TBL Plus and B27, were subjected to testing. TBL Plus steel was characterised by the smallest wear irrespective of the soil type. In turn, the highest values of the wear were noted in the light soil for Hardox 500, in the medium soil for XAR 600, while in the heavy soil for B27. Based on the obtained results, a high correlation coefficient was noted, with the highest values obtained for light and heavy soils.

20 July 2023 in Materials
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JAN LEAN TAIJAN LEAN TAI
JAN LEAN TAI
Mohamed Thariq SultanMohamed Thariq Sultan
Mohamed Thariq Sultan
Andrzej ŁukaszewiczAndrzej Łukaszewicz
Andrzej Łukaszewicz
FSFarah Syazwani Shahar
Farah Syazwani Shahar
Wojciech TarasiukWojciech Tarasiuk
Wojciech Tarasiuk
Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
On-stream inspections are the most appropriate method for routine inspections during plant operation without undergoing production downtime. Ultrasonic inspection, one of the on-stream inspection methods, faces challenges when performed at high temperatures exceeding the recommended 52 °C. This study aims to determine the ultrasonic velocity and attenuation with known material grade, thickness, and temperatures by comparing theoretical calculation and experimentation, with temperatures ranging between 30 °C to 250 °C on low-carbon steel, covering most petrochemical equipment material and working conditions. The aim of the theoretical analysis was to obtain Young’s modulus, Poisson’s ratio, and longitudinal velocity at different temperatures. The experiments validated the theoretical results of ultrasonic change due to temperature increase. It was found that the difference between the experiments and theoretical calculation is 3% at maximum. The experimental data of velocity and decibel change from the temperature range provide a reference for the future when dealing with unknown materials information on site that requires a quick corrosion status determination.

30 October 2022 in Materials
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KLKrzysztof Ligier
Krzysztof Ligier
MZMartyna Zemlik
Martyna Zemlik
Magdalena LemechaMagdalena Lemecha
Magdalena Lemecha
ŁKŁukasz Konat
Łukasz Konat
Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
This paper presents the results of wear tests of three types of commercial abrasion-resistant steels. The samples, cut from commercially available sheets of metal, were subjected to wear tests to a total friction path of 20,000 m. The tests were provided using the “rotating bowl” method in three types of natural soil masses. The soil moisture and test parameters were kept constant. The tests were carried out in six replications for each material. The testing results indicate that hardness does not determine the resistance to abrasive wear, which is supported by the weight loss results for particular materials. Hardox 600 steel, which is not characterized by the highest hardness, exhibited the lowest weight loss value compared to the other materials in all test soils. For the light soil, the weight loss for Hardox 600 was approx. 1.3 times lower than for Hardox 500 steel and approx. 1.6 times higher than for Hardox Extreme steel. With regards to the medium and heavy soil, the weight losses for Hardox 600 in relation to Hardox 500 steel were approx. 1.7 and 1.6 times lower, respectively, while in relation to Hardox Extreme steel the weight losses were 1.5 and 1.7 times higher, respectively.

21 July 2022 in Materials
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MZMartyna Zemlik
Martyna Zemlik
ŁKŁukasz Konat
Łukasz Konat
Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
The paper discusses the microstructural, chemical and tribological properties of the selected low-alloy, high-strength martensitic boron steels with a hardness of 500–600 HBW. These materials, due to their increased strength, and thus resistance to abrasive wear, are widely used in the mining, agricultural or building industries. Grades such as XAR, TBL and Creusabro were subjected to a comparative analysis. As a result of the conducted research, an attempt was made to determine the relation between the microstructural properties, chemical composition, hardness and abrasive wear resistance of the above-mentioned metallic materials belonging to the same material group. The scope of work involved a metallographic analysis, including the examination of the microstructure with an analysis of the prior austenite grain size. Tribological tests were carried out with the use of a T-07 tester, which is designed for testing abrasive wear resistance in the presence of a loose abrasive. As a result, it was found that the coefficient of relative abrasion resistance kbAV in relation to as-normalized C45 steel is equal to 0.9–1.25 and may even have the same value among materials of different hardness in the as-delivered state.

31 August 2016 in Tribologia
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ŁKŁukasz Konat
Łukasz Konat
Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
KKKarol Kołakowski
Karol Kołakowski
The paper presents the structure and the results of abrasive wear resistance tests of XAR®600, TBL PLUS, and B27 steel. As a result of the tests conducted by means of light and scanning microscopy, it has been proven that these types of steel are characterised by subtle differences in their structures, affecting their strength and performance properties. In the delivered condition, all types of steel are characterised by a fine-grained structure with post-martensitic orientation with insets of carbide phases. The structural type of the discussed steel types disclosed in the course of the research, as well as the results of the conducted spectral analyses of the chemical composition, indicate that their properties are shaped in the course of specialist procedures of thermomechanical rolling. According to the above-mentioned test results, it can be concluded that the analysed steel types were designed in compliance with the canons of materials engineering in relation to low-alloy steel resistant to abrasive wear. Due to this, the obtained results of the structural tests of XAR®600, TBL PLUS, and B27 steel were subjected to verification in the course of abrasive wear resistance tests by means of the “spinning bowl” method. The tests, conducted in real soil masses – loamy sand, light clay, and normal clay, compared with the results of hardness measurements, indicated a strict dependence of abrasive wear resistance ratios as a function of structure and the heat treatment condition of the tested types of steel. All the obtained test results were referred to 38GSA steel in a normalised condition.

1 December 2015 in Tehnicki vjesnik - Technical Gazette
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JKJolanta Krolczyk
Jolanta Krolczyk
Grzegorz KrolczykGrzegorz Krolczyk
Grzegorz Krolczyk
Stanisław LegutkoStanisław Legutko
Stanisław Legutko
Jerzy NapiórkowskiJerzy Napiórkowski
Jerzy Napiórkowski
Sergej HlochSergej Hloch
Sergej Hloch
ETEwelina Tama
Ewelina Tama
Today, most contemporary organisations are facing many dilemmas, the essence of which is the determination of the ways of acquisition or maintenance of their position in the competitive environment. Companies have to continuously...