Wyniki wyszukiwania - BazTech

1

Wpływ jakości diamentu monokrystalicznego na odporność narzędzi na zużycie oraz wydajność skrawania

Jemielniak Krzysztof

Mechanik

|

2025

|

R. 98, nr 1

36

PL

Narzędzia z diamentu monokrystalicznego (MKD) są powszechnie stosowane w ultraprecyzyjnej obróbce form wykonanych z metali nieżelaznych. Jednak żywotność takich narzędzi silnie zależy od jakości naturalnych i syntetycznych MKD. W artykule przedstawiono wyniki analizy jakości naturalnych i syntetycznych MKD na podstawie pomiaru ich dwójłomności i jej wpływu na trwałość ostrza.

2

Analytical study of durability and contact characteristics of metal-polymer composite sliding bearings for means of transport

Chernets Myron, Wrona Rafał, Chernets Yuriy

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2024

|

z. 123

5--21

EN

The field of application of metal-polymer bearings is vast: transport of various types, processing industry equipment, medical equipment, various types of maintenance equipment, etc. With the use of the developed generalized author's analytical method of metal-polymer plain bearings on the basis of which it is laid the author's research methodology of materials wear kinetics at sliding friction (dry, lubricated), calculation of their durability is carried out. Contact parameters are also determined. Metal-polymer bearings with a bushing made of PA6, PA66 polyamide and PA6 based composites filled with glass (PA6 + 30GF) and carbon (PA6 + 30CF) dispersed fibres, molybdenum disulphide (PA6 + MoS2) and oil filled cast polyamide (PA6 + oil) are considered. These polyamides (unfilled and filled), as self-lubricating materials, are widely used in this type of dry friction sliding bearings. The predictive estimation of durability of investigated bearings depending on loading, polymer materials Young's modulus, their wear resistance and sliding friction coefficient is executed. Regularities of change from the specified factors of bearing's durability and the maximum contact pressures are established. Experimental indicators, diagrams, and wear resistance characteristics of the specified polymeric materials are presented. The results of researches of sliding friction coefficient and modulus of elasticity for carbon steel (0.45%C) – polyamides tribocouples are presented.

3

Possibility of Introducing Molybdenum Disulfide into the Layer During Gas Nitriding

Kazimierski Grzegorz, Stodolny Jerzy, Goły Marcin, Wróbel Rafał J.

Tribologia

|

2024

|

nr 3

57--71

EN

The aim of this study was to attempt the introduction of molybdenum disulfide as an excellent solid lubricant into the nitrided coating before the nitriding process. In the commonly applied methods, nitriding precedes depositing MoS2 powder on a surface. In the method described in the article, this order was reversed and the surface intended for frictional contact was first coated with a layer of MoS2 powder and then subjected to gas nitriding in an ammonia atmosphere. The most important observations indicate that the presence of MoS2 on the surface before nitriding did not hinder the thermochemical treatment, and the applied molybdenum disulfide powder was transferred to the surface layer after nitriding. Some of the MoS2 powder was embedded in the upper regions of the white layer, and the presence of some powder was found on the surface of the nitrided layer. Such a result obtained in the new technological variant is a desirable circumstance that allows for better utilization of the lubricating properties of the new coating.

PL

Celem pracy była próba wprowadzenia dwusiarczku molibdenu jako doskonałego stałego smaru do powłoki azotowanej przed procesem azotowania. Znane metody głównie stosują najpierw azotowanie, a następnie osadzanie proszku MoS2 na takiej powierzchni. Wadą tych metod jest jedynie powierzchniowa obecność MoS2 na powłoce. W opisanej w artykule metodzie kolejność ta została odwrócona i w pierwszej kolejności na powierzchnię przeznaczoną do kontaktu ciernego nałożono warstwę proszku MoS2,którą następnie poddano azotowaniu gazowemu w atmosferze amoniaku. Najważniejsze obserwacje wskazują, że obecność MoS2 na powierzchni przed azotowaniem nie utrudniała procesu obróbki cieplno-chemicznej, a zastosowany proszek dwusiarczku molibdenu po azotowaniu przeniósł się na warstwę wierzchnią. Część proszku MoS2 została osadzona w górnych obszarach białej warstwy i stwierdzono obecność pewnej ilości proszku na powierzchni warstwy azotowanej. Uzyskany wynik w nowym wariancie technologicznym jest pożądaną okolicznością, która pozwala na lepsze wykorzystanie właściwości smarnych nowej powłoki.

4

Analysis of the Microstructure And Mechanical Properties of Duplex Steel Joints

Witkowska Małgorzata, Kowalska Joanna, Chronowska-Przywara Kinga

Tribologia

|

2024

|

nr 1

147--158

EN

The article presents a study, the aim of which was to analyze the microstructure and mechanical properties of welded joints of austenitic-ferritic duplex steel X2CrMnNiN21-5-1. This steel is characterized by good resistance to various types of corrosion, good strength properties and good weldability. Due to all these advantages, it is used in many industry sectors, and the main joining techniques are welding technologies. In this study, two joining techniques were used, SMAW (Shielded Metal Arc Welding) and GTA (Gas Tungsten Arc). The obtained welded joints were subjected to: macroscopic and microscopic metallographic tests, mechanical tests (static bending test and microhardness measurements), diffraction tests, and wear resistance tests. The results showed that the microhardness of the welds is similar and does not depend on the welding method used. In the microstructure of the analyzed joints there are two phases: austenite (γ) and ferrite (δ), with different morphologies depending on the welding conditions, which affect the phase transformations. Material wear within the weld is greater than in the base material.

PL

Celem badań była analiza mikrostruktury i własności mechanicznych złączy spawanych stali austenityczno-ferrytycznej typu duplex X2CrMnNiN21-5-1. Stal ta charakteryzuje się dobrą odpornością na różnego rodzaju korozje, dobrymi własnościami wytrzymałościowymi i dobrą spawalnością. Dzięki tym wszystkim zaletom znajduje zastosowanie w wielu gałęziach przemysłu, a głównymi technikami jej łączenia są technologie spawalnicze. W pracy zastosowano dwie techniki łączenia metodą SMAW (Shielded Metal Arc Welding) i GTA (Gas Tungsten Arc). Uzyskane złącza spawane poddano: badaniom metalograficznym makro- i mikroskopowym, badaniom mechanicznym (statyczna próba zginania i pomiary mikrotwardości), badaniom dyfrakcyjnym oraz badaniom odporności na zużycie. Wyniki badań pokazały, że mikrotwardości spoin są zbliżone i nie zależą od zastosowanej metody spawania. W mikrostrukturze analizowanych złącz występują dwie fazy austenit (γ) i ferryt (δ) o zróżnicowanej morfologii zależnej od warunków spawania, które wpływają na przemiany fazowe. Zużycie materiału w obrębie spoiny jest większe aniżeli w materiale rodzimym.

5

Wpływ urządzeń drukujących i czasu postpolimeryzacji na właściwości mechaniczne i tribologiczne materiałów światłoutwardzalnych stosowanych w technologii druku 3D DLP

Snarski-Adamski Andrzej, Pieniak Daniel, Krzysiak Zbigniew, Michalczewski Remigiusz, Firlej Marcel

Przemysł Chemiczny

|

2024

|

T. 103, nr 2

301--306

PL

Technika wytwarzania przyrostowego AM (additive manufacturing) 3D DLP (digital light processing) zapewnia akceptowalne właściwości mechaniczne materiału, dobre odwzorowanie wymiarów geometrycznych i małą chropowatość powierzchni. Przedstawiono wyniki badań właściwości mechanicznych i tribologicznych wybranego popularnego światłoutwardzalnego tworzywa polimerowego Phrozen Resin Flex. Wydrukowano i opracowano do badań próbki o kształcie krążków i prostopadłościanów za pomocą drukarek 3D Phrozen Shuffle Lite (PSL) i Phrozen Sonic Mini (PSM). Przy takich samych parametrach wydruku warstwowego wykazano wpływ urządzenia drukującego i czasu dodatkowej fotopolimeryzacji na twardość, moduł sprężystości i odporność na zużycie badanego materiału.

EN

Com. light-cured acrylic polymer resin Phrozen Resin Flex was used to print disc- and cuboid-shaped samples using Phrozen Shuffle Lite and Phrozen Sonic Mini 3D printers. The obtained samples were tested for indentation hardness, surface elasticity modulus, surface stiffness and indentation creep, as well as roughness, friction and wear resistance under dry sliding friction conditions. With the same layered printing parameters, the effect of the printing device and addnl. photopolymerization time on the mech. and tribol. properties of the tested material was demonstrated.

6

Durability and wear resistance of sliding electric contacts in electric transport

Drahobetskyi Volodymyr, Moloshtan Dmytro, Symonova Anastasiia, Nikitina Alyona, Zagirnyak Mykhaylo

Przegląd Elektrotechniczny

|

2024

|

R. 100, nr 1

275--278

EN

This paper researches the durability and wear resistance of sliding electric contacts in urban electric transport. It proposes the use of additional impulse loading in powder metallurgy techniques to reduce wear and enhance fatigue force. The analysis highlights the importance of sustainable solutions in addressing the challenges of urban passenger transportation. Promising directions for further research include the improvement of manufacturing technology and the use of amorphous alloys.

PL

W artykule zbadano trwałość i odporność na zużycie ślizgowych styków elektrycznych w miejskim transporcie elektrycznym. Proponuje się zastosowanie dodatkowego obciążenia impulsowego w technikach metalurgii proszków w celu zmniejszenia zużycia i zwiększenia siły zmęczeniowej. Analiza podkreśla znaczenie zrównoważonych rozwiązań w stawianiu czoła wyzwaniom miejskiego transportu pasażerskiego. Obiecujące kierunki dalszych badań obejmują doskonalenie technologii wytwarzania i zastosowanie stopów amorficznych.

7

Zalety kołków sprężystych zwijanych ze stali nierdzewnej chromowej 420

Pasko Michael

Napędy i Sterowanie

|

2024

|

R. 26, nr 6

40--41

PL

Kołki zwijane są stosowane w wielu branżach, w tym motoryzacyjnej, medycznej, ciężkiego sprzętu, wojskowej, lotniczej i produktów konsumenckich. W zastosowaniach wymagających połączenia wysokiej wytrzymałości, doskonałej odporności na zużycie i odporności na korozję, nierdzewna chromowa stal martenzytyczna 420 oferuje szereg zalet technicznych oraz stanowi rzetelne i racjonalne pod względem kosztów rozwiązanie. [...] Firma SPIROL produkuje kołki sprężyste od 1948 roku...

8

Abrasive Wear Resistance of High-Entropy AlCoCuFeNi Alloy in SiC Mixture

Chrzan K., Kalandyk B., Grudzień-Rakoczy M., Rakoczy Ł., Cichocki K.

Archives of Foundry Engineering

|

2024

|

Vol. 24, iss. 3

123--128

EN

The paper presents the results of dimensional and shape analysis of additively manufactured shaped parts of foundry moulds; specifically, shaped gate valve inserts made of DIEVAR steel used in the die-casting process of aluminium alloys. The paper aims to provide a comprehensive overview of dimensional and shape analysis during the manufacturing of shaped mould parts before their use in foundry operating conditions. The manufacturing operations include additive manufacturing, heat treatment, machining, and applying a protective coating. Based on these technological operations, the required component accuracy is achieved before application in the operating conditions. The dimensional and shape analysis was measured by 3D scanning and 3D measuring methodology on a coordinate measuring machine. The ROMER ABSOLUTE ARM 3D scanning arm and the THOME PRÄZISION coordinate measuring machine were used for the measurements. The paper presents findings in the development and application of additive manufacturing technologies in engineering metallurgy.

9

Wear resistance of hard anodic coatings fabricated on 5005 and 6061 aluminum alloys

Kwolek Przemysław, Obłój Andrzej, Kościelniak Barbara, Buszta Regina, Tokarski Tomasz, Krupa Krzysztof, Gradzik Andrzej, Nowak Wojciech J., Wojnicki Marek, Motyka Maciej

Archives of Civil and Mechanical Engineering

|

2024

|

Vol. 24, no. 2

art. no. e51, 2024

EN

The wear resistance of hard anodic coatings fabricated on 5005 and 6061 aluminum alloys was determined. The Taber abrasion test, ball-on-disc tribological test, and scratch test at constant load were conducted. The wear resistance of the hard coating fabricated on the 6061 alloy was found to be higher compared to the coating on the 5005 alloy. This is related to the lower nanoscale porosity of the former, and the higher hardness of the 6061 alloy compared to 5005. The specific wear rates for the load of 4.905 N were equal to 1.70 × 10−5 and 1.02 × 10−5 mm3 N−1 m−1 for the coatings on 5005 alloy and 6061 alloy, respectively. In the case of the hard anodized 5005 alloy, the specific wear rate increased with increasing load to 4.56 × 10−5 mm3 N−1 m−1 whereas for anodized 6061 alloy to 1.98 × 10−5 mm3 N−1 m−1. It was also found that the protective properties of the coating on 6061 alloy do not change significantly across the coating thickness.

10

The effect of dispersing agents on the electrophoretic deposition, morphology and adhesion strength of multicomponent TiN/PTFE/PEEK coatings

Fiołek Aleksandra, Zimowski Sławomir, Moskalewicz Tomasz

Archives of Civil and Mechanical Engineering

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2024

|

Vol. 24, no. 2

art. no. e48, 2024

EN

In this work, multicomponent PEEK coatings with PTFE particles and TiN nanoparticles were developed on Ti-6Al-4V alloy substrates using electrophoretic deposition (EPD) and post-EPD heat treatment. Three different polyelectrolytes involving chitosan, PAZO and sodium alginate were used to enable the co-deposition of all particles on one electrode. All polyelectrolytes were effective and enabled coating deposition through electrosteric stabilization of suspension. The EPD mechanism consisted of the adsorption of the dispersant on the surface of the particles and the imparting of a positive (chitosan) or negative (PAZO, sodium alginate) charge. Heat treatment densified the coatings but also caused microcrack formation in the coating with chitosan, shrinkage of the polymers in the coating with PAZO, and open porosity in the coating with sodium alginate. Coatings obtained from suspension with chitosan showed excellent adhesion strength and scratch resistance, higher that those deposited from suspensions containing PAZO or alginate. The introduction of TiN and PTFE particles into the PEEK matrix resulted in a simultaneous reduction of the friction coefficient and wear rate of the titanium alloy in the case of coatings with chitosan and alginate. These coatings are promising for improving the wear and friction properties of titanium alloys.

11

Analysis of wear resistance of metallic-reinforced polyurethane resin composites for sheet metal forming

Wiewióra Marcel, Żaba Krzysztof, Kuczek Łukasz, Balcerzak Maciej, Marcin Madej

Advances in Materials Science

|

2024

|

Vol. 24, nr 3(81)

18--29

EN

The paper presents the results of testing the wear resistance and coefficient of friction (COF) tools made of SikaBeresin® F50 polyurethane resin intended for dies and punches for the cold sheet metal forming process. Seven sets of composite tools (rotating rings) additionally reinforced with waste metallic powders from Al and Cu alloys (5-20% by volume) from the dry cutting process of pipes and rods were tested. Wear resistance tests and determination coefficient of friction were carried out using the T-05 block-on-ring tribotester. The tests were performed for heat and corrosion resistant sheets made of nickel alloy AMS5599 (Inconel 625), iron alloy AMS5510 (321) and aluminum alloy sheets AMS4026 (6061-T4). Composite tools with the addition of 20% aluminum powder (A+B+C+20%Al) tested with a specimen of steel alloy AMS5510 and nickel alloy AMS5599 were characterized by the lowest wear resistance. In each case, the composite rotating ring without reinforcements was characterized by the lowest coefficient of friction. The use of Cu powder reinforcements in each case had a positive effect on increasing wear resistance. The best wear resistance of 0.011% was obtained for composite rotating ring with the addition of 10% copper powder paired with specimen of nickel alloy AMS5599 sheet.

12

The influence of carbide reinforcement on the properties of sintered aluminium alloy matrix composites

Szewczyk-Nykiel Aneta

Technical Transactions

|

2023

|

Vol. 120, iss. 1

art. no. e2023005

EN

Based on the commercial aluminium alloy powder blend (Alumix 431D) metal matrix composites reinforced with particles of SiC as well as TiC were produced by conventional powder metallurgy technology and the effect of the type and amounts of reinforced particles on the selected properties and microstructure of sintered composites were investigated. In particular, the densification behaviour, the wear resistance and the corrosion resistance in 3.5% NaCl solution were identified. It was stated that both the type and the weight fraction of carbide used as particulate reinforcement have a great impact on the properties of aluminium alloy matrix composites. It was shown that the introduction of titanium carbide has a more favourable effect on the properties of sintered Alumix 431D matrix composites in comparison to silicon carbide and the optimum content of TiC in composite is 4 wt. % due to the highest hardness, wear resistance (wear rate of 2.865·10 ̄ ³ mm³/m) and simultaneously the best corrosion resistance (corrosion rate of 0.005 mm/year).

13

Powłoki natryskiwane plazmowo dla potrzeb przemysłu chemicznego

Morel Sławomir

Przemysł Chemiczny

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2023

|

T. 102, nr 4

355--361

PL

Opisano przeznaczenie i zakres zastosowań powłok natryskiwanych cieplnie. Scharakteryzowano plazmę stosowaną do natryskiwania powłok. Dokonano ogólnej charakterystyki najczęściej stosowanych materiałów powłokowych i wyszczególniono ważniejsze właściwości powłok decydujące o ich przydatności dla potrzeb przemysłu i gospodarki. Przytoczono ważniejsze przykłady eksploatacji urządzeń pracujących z natryskanymi powłokami, zamieszczając osiągnięte efekty oddziaływania powłok na wzrost trwałości i efektywności pracy cieplnej.

EN

A review, with 14 refs, of the range of applications of thermal sprayed coatings using plasma. The plasma used for spraying coatings was characterized. The general characteristics of the most commonly used coating materials were presented, and the most important coating properties detg. their suitability for industrial applications were indicated. Examples of the operation of devices working with sprayed coatings were given, including the effects of coatings on increasing the durability and efficiency of thermal operation.

14

The Influence of Pearlite Present in the Microstructure of GX120MnCr13 Cast Steel on Wear Resistance

Kalandyk Barbara, Zapała Renata, Sulima Iwona, Furmańczyk Piotr, Kasińska Justyna

Archives of Foundry Engineering

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2023

|

Vol. 23, iss. 4

145--156

EN

The article presents the results of metallographic and tribological tests on GX120MnCr13 cast steel that was previously subjected to heat treatment (including solution treatment from 1100°C and isothermal holding at 250, 400, and 600°C for 100 hours). The temperatures of the isothermal holding process were selected in order to reflect the possible working conditions of the cast elements that can be made of this cast steel. Wear tests were carried out under dry friction conditions using the ball-on-disc method using a ZrO2 ball as a counter-sample. The tests were carried out with a load of 5 N. The influence of the long-term isothermal holding process on the microstructure of the tested cast steel was analysed by light and scanning microscopy; however, abrasion marks were also examined using a confocal microscope. Based on the tests conducted, it was found that in the microstructures of the sample after solution treatment and samples that were held in isothermal C, the grain boundary areas were enriched in Mn and Cr compared to the areas inside the grains. Pearlite appeared condition at 250 and 400 in the sample that was heated (or held in isothermal holding) at 600°C; its share reached 41.6%. The presence of pearlite in the austenitic matrix increased the hardness to 351.4 HV10. The hardness of the remaining tested samples was within a range of 221.8-229.1 HV10. Increasing the hardness of the tested cast steel directly resulted in a reduction in the degree of wear as well as the volume, area, and width of the abrasion marks. A microscopic analysis of the wear marks showed that the dominant process of the abrasive wear of the tested friction pair was the detachment and displacement of the tested material through the indentation as a result of the cyclical impact of the counter sample.

15

Nitriding of hardfaced layers as a method of improving wear resistance of hot forging tools

Widomski Paweł, Kaszuba Marcin, Sokołowski Paweł, Lange Artur, Walczak Mariusz, Długozima Marcin, Gierek Mateusz, Chocyk Dariusz, Gładyszewski Grzegorz, Boryczko Bożena

Archives of Civil and Mechanical Engineering

|

2023

|

Vol. 23, no. 4

art. e241, 1--16

EN

The article deals with novel hybrid layers combining hard facing and nitriding to improve forging tool durability. It includes a study of the nitriding capabilities of hard facings made of typical materials used to repair key groups of hot forging tools. Tests were conducted on samples and on tools in forging processes. Tests on samples included hard facing, nitriding, microstructure, micro hardness, XRF phase analysis and abrasive wear tests. Experimental tests on forging tools included operational tests and comprehensive wear analysis by scanning, macroscopic and microscopic observations by light and scanning microscopy, and analysis of wear mechanisms. Tests on the samples confirmed the positive effect of nitriding on performance properties at room and elevated temperatures. They revealed the reduced susceptibility to nitriding of some welds and the variable composition of nitrides present on the surface of the samples, which has a key effect on the observed wear mechanisms in the ball-on-disc test. Operational tests showed the effect of improved durability, which is greatest for the DO*15 (Fe–Cr– Mo–W)+nitriding layer which is due to the increased hardness of the weld itself and the increased susceptibility to nitriding.

16

Effects of primary sintering on microstructure and properties of friction stir back extruded Cu-Ti2SnC wire composite

Jahani Amirhossein, Jamshidi Aval Hamed, Rajabi Mohammad, Jamaati Roohollah

Archives of Civil and Mechanical Engineering

|

2023

|

Vol. 23, no. 2

art. no. e136, 2023

EN

The present work investigated the effects of primary sintering on the microstructure, mechanical, electrical, and wear properties of the Cu-5vol%Ti2SnC wire composite fabricated by friction stir back extrusion process. The results showed that the grain size of the final product increased by performing a sintering treatment before the FSBE process. It is important to note that the grain size in the composite sample was coarser than the sample without reinforcement after the extrusion process. Furthermore, since the effect of temperature predominates over plastic strain, a coarser grain was formed in the composite samples. Compared to the center, the grain size of the near surface of extruded wires was slightly finer. By performing the sintering treatment and applying heat during the treatment, it is possible to form the Cu81Sn22 phase, which can increase the Cu81Sn22 phase content formed during FSBE. The interface quality was significantly improved by the sintering treatment before the FSBE process. The sintering treatment increased the strength, elongation, electrical conductivity, and wear resistance of Cu-Ti2SnC composite wire by 4, 13, 2, and 5%, respectively.

17

Hob wear prediction based on simulation of friction, heat fluxes, and cutting temperature

Hrytsay Ihor, Stupnytskyy Vadym

Archive of Mechanical Engineering

|

2023

|

LXX, nr 2

271--286

EN

Based on comprehensive interrelated mathematical and graphical-analytical models, including 3D cut layers and simulation of contact, strain, force, and thermal processes during gear hobbing friction forces, heat fluxes, and temperature on the teeth of the hob surface are investigated. Various physical phenomena are responsible for their wear: friction on contact surfaces and thermal flow. These factors act independently of each other; therefore, the worn areas are localized in different active parts of the hob. Friction causes abrasive wear and heat fluxes result in heat softening of the tool. Intense heat fluxes due to significant friction, acting on areas of limited area, lead to temperatures exceeding the critical temperature on certain edges of the high-speed cutter. Simulation results enable identification of high-temperature areas on the working surface of cutting edges, where wear is caused by various reasons, and make it possible to select different methods of hardening these surfaces. To create protective coatings with maximum heat resistance, it is advisable to use laser technologies, electro spark alloying, or plasma spraying, and for coatings that provide reduction of friction on the surfaces – formation of diamond-containing layers with minimum adhesion properties and low friction coefficient on the corresponding surfaces.

18

Influence of Pre-Hardened Gx120mn13 Cast Steel on the Tribological Properties under Technically Dry Friction

Kalandyk Barbara, Zapała Renata, Madej Monika, Kasińska Justyna, Piotrowska Katarzyna

Tribologia

|

2022

|

nr 3

17--24

EN

This paper presents the results of tribological tests on high manganese GX120Mn13 cast steel under technically dry friction conditions. The tests were carried out using a TRB3 ball-on-disc tribometer using a 6mm-diameter SiC ball as a counter-sample for a specimen made of GX120Mn13 cast steel containing a localised prehardening area on the test surface with a hardness of approximately 597 HV10 (the non-hardened area had a hardness of approximately 325–364 HV10). During the test, the ball travelled in a 16.68 mm diameter circle and passed through both hardening and non-hardened areas. The resulting erosion marks were assessed using an optical profilometer and scanning microscope tests, which showed that the maximum depth of erosion in the previously hardening area was 0.77 µm and was more than twice as deep as in the non-hardened areas surveyed. In contrast, the area of attrition was twice as small as in the non-hardened area located in the axis of the previously applied load and more than three times smaller, but in the area located on the side of the axis and 8.34 mm away from it. Thus, from the point of view of the abrasion resistance of GX120Mn13 cast steel, the validity of its prior hardening before the operation was confirmed.

PL

W artykule przedstawiono wyniki badań tribologicznych wysokomanganowego staliwa GX120Mn13 w warunkach tarcia technicznie suchego. Badania przeprowadzono przy użyciu tribometru TRB3 typu ball–on– disc stosując jako przeciwpróbkę kulkę z SiC o średnicy 6mm dla próbki wykonanej ze staliwa GX120Mn13 zawierającej na powierzchni badanej lokalny obszar wcześniej umocniony o twardości ok. 597 HV10 (obszar nieumocniony posiadał twardość ok 325–364 HV10). Kulka w czasie testu poruszała się po okręgu o średnicy 16.68 mm i przechodziła zarówno przez obszar umocniony, jak i nieumocniony. Otrzymane ślady wytarcia oceniano za pomocą badań wykonanych na profilometrze optycznym i mikroskopie skaningowym. Na podstawie przeprowadzonych badań wykazano, że w obszarze wcześniej umocnionym maksymalna głębokość wytarcia wynosiła 0.77 µm i była ponad dwukrotnie mniejsza niż w badanych obszarach nieumocnionych. Z kolei pole wytarcia było dwukrotnie mniejsze niż w obszarze nieumocnionym, znajdującym się w osi przyłożonego wcześniej obciążenia i ponad trzykrotnie mniejsze w porównaniu z obszarem znajdującym się z boku osi i oddalonym od niej o 8.34 mm. Tym samym, z punktu widzenia odporności na zużycie ścierne staliwa GX120Mn13, potwierdzono słuszność jego wcześniejszego umocnienia przed eksploatacją.

19

Evaluation of Wear Mechanisms of Graphites Used for Crystallisers for Continuous Casting

Brudny Anna, Kulasa Joanna, Juszczyk Barbara, Myalski Jerzy, Roskosz Stanisław, Wycisk R., Kwaśniewski Paweł, Strzępek Paweł, Poręba Marek

Archives of Foundry Engineering

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2022

|

Vol. 22, iss. 4

109--115

EN

This paper presents the results of research concerning the evaluation of tribological properties of graphite materials used, among others, for crystallisers for continuous casting of non-ferrous metals and their alloys. Graphite materials differing not only in their physical properties but also in the technology of their production were selected from a wide range of commercially available products. Wear resistance investigations of the tested graphite materials were carried out on a pin-on-disc tribometer under technically dry friction conditions on a sliding distance of 1000 m. A constant load but variable speed was used in the tests. The mean value of the coefficient of friction and the wear of the material were determined based on the tribological tests carried out. It was observed that as the speed increases, the average value of the coefficient of friction decreases, while the wear increases. A microstructural analysis of the wear track showed that the friction mechanism depends mainly on the graphite formation technology, which is related to the microstructure of the tested materials, and to a lesser extent to their physical and mechanical properties. Varying the speed values made it possible to trace changes in the wear mechanism, on the basis of which it is possible to predict the durability and reliability of graphite crystalliser operation.

20

Effect of friction surfacing parameters on the microstructural, mechanical properties, and wear characteristic of Al‑Cu‑Mg alloy coating reinforced by nickel aluminide

Farajollahi Ramezanali, Aval Hamed Jamshidi, Jamaati Roohollah

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 2

art. no. e75, 1--18

EN

This research has studied the microstructure, mechanical properties, and tribological properties of AA2024-Al3NiCu composite coating fabricated by friction surfacing. The Al3NiCu intermetallic was created in the aluminum matrix by adding nickel during the stir casting process and then performing the homogenization treatment. The results showed that with increasing the axial feeding rate from 87.5 to 125 mm/min and the rotational speed from 600 to 800 rpm, the coating efficiency grew up to 79%. Moreover, no significant microstructural differences (grain size, precipitate size, and morphology) were observed in different parts of the coating. Applying the coating at a rotational speed of 800 rpm, a traverse speed of 125 mm/min, and an axial feeding rate of 125 mm/min raised the hardness and shear strength of the AA2024 aluminum alloy substrate by 17% and 21%, respectively, while lowering its wear rate by 37%.