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1

The Effect of HVOF Spray Distance on Solid Particle Erosion Resistance of WC-based Cermets Bonded by Co, Co-Cr and Ni Deposited on Mg-alloy Substrate

Jonda Ewa, Łatka Leszek, Lont Aleksandra, Gołombek Klaudiusz, Szala Mirosław

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

115--128

EN

Magnesium alloys are very interesting engineering materials because of their high strength-to-density ratio. On the other hand, they are characterized by low hardness as well as low erosion resistance. Because of these reasons, their applications in the industry are very limited. The article presents the results of the high velocity oxy-fuel (HVOF) spraying of the hard cermet coatings onto AZ31 magnesium alloy substrate. Three feedstock powders were used in the process with composition (wt.%): WC-12Co, WC-10Co-4Cr and WC-20Cr3C2Ni. The spray distance (SD) was selected as a variable parameter with values equal to 320 and 400 mm. Observations carried out under a scanning electron microscope (SEM) revealed a typical HVOF-sprayed microstructure with a compact structure and low porosity (below 3 vol.%). The hardness of the manufactured coatings, ranging from 912 HV0.2 to 1328 HV0.2, what was significantly higher than the substrate. The solid particle erosion tests were carried out according to the ASTM G76-04 standard. Erosive experiments were done for 30°, 60° and 90° inclination angles of the nozzle using Al2O3 abrasive. Erosion tests confirm that cermets exhibit substantial erosion resistance better than the substrate. The highest erosion resistance was noted for WC-10Co-4Cr coatings. The erosion rate for cermet coatings was mostly below 0.9 mg/min, whereas for the AZ31 it was more than 1.5 mg/min. In the case of the average erosion value, it was between 12 and 22 times lower than for the substrate. Results analysis reveal that shorter spray distance decreases porosity, increases hardness, and finally supports erosion resistance of the cermets.

2

Effect of hBN on Wear of AlCrN-Coated Spark Plasma - Sintered TiB2/Ti Composites at Temperatures up to 900°C

Łuszcz Maciej, Michalczewski Remigiusz, Kalbarczyk Marek, Osuch-Słomka Edyta, Molenda Jarosław, Liu Le, Antonov Maksim, Hussainova Irina

Tribologia

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2022

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nr 1

43--55

EN

In this work, hexagonal boron nitride powder was used for the lubrication of an interface of TiB2/Ti composite protected by an AlCrN coating and a ceramic Si3N4 ball. The wear behaviour of this tribo-pair in an oscillating motion was studied with an SRV tribotester at the temperature range from room temperature to 900 °C. The action of hexagonal boron nitride as a solid lubricant was analysed with the use of a 3D microscopy and energy-dispersive spectroscopy. The test results confirmed that under high-temperature conditions, the use of hexagonal boron nitride as a solid lubricant does not increase the wear resistance of the TiB2/Ti composite. The use of the AlCrN coating significantly reduces wear at the temperature up to 600 °C only, while the combined use of the AlCrN coating and hBN lubrication provides effective protection against wear even at the temperature up to 900 °C. Therefore, the synergy of the anti-wear action of the coating and the solid lubricant was proved.

PL

W niniejszej pracy wykorzystano heksagonalny azotek boru (hBN) jako smarującą międzywarstwę między podłożem kompozytowym z TiB2/Ti chronionym powłoką AlCrN a przeciwpróbką – kulką ceramiczną wykonaną z Si3N4. Testy tribologiczne wykonano z zastosowaniem stanowiska SRV. Zbadano zużycie ścierne w ruchu oscylacyjnym w zakresie od temperatury pokojowej do 900°C. Rola hBN jako stałego środka smarowego została zbadana z wykorzystaniem mikroskopii 3D oraz spektroskopii rentgenowskiej z dyspersją energii. Wyniki przeprowadzonych badań potwierdziły, że w warunkach wysokich temperatur zastosowanie heksagonalnego azotku boru pełniącego funkcję smaru stałego nie powoduje zwiększenie odporności na zużycie kompozytu TiB2/Ti. Zastosowanie powłoki AlCrN powoduje znaczącą redukcję zużycia jedynie do temperatury 600°C, podczas gdy łączne zastosowanie powłoki AlCrN i smarowania hBN stanowi skuteczną ochronę przed zużyciem nawet do 900°C. Wykazano zatem synergię przeciwzużyciowego działania powłoki i smaru stałego.

3

Parametric optimisation of microhardness on heat-treated electroless Ni-YSZ cermet coating

Bahiyah Baba N., Ghazali A. S., Abdul Rahman A. H., Sharif S

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 112, nr 1

33--41

EN

Purpose: The paper discusses the parametric optimisation of the electroless Ni-YSZ cermet coating microhardness upon heat treatment. Heat treatment is a process to increase the mechanical properties of the electroless nickel coating and it can be enhanced by manipulating its parameters. Parametric optimisation is conducted by the design of experiment full factorial 3x3 with 27 runs. Treating temperature, treating time and ceramic particle size parameters at 3-level are evaluated using statistical tool ANOVA in Minitab20. Design/methodology/approach: Ni-YSZ cermet coating is deposited onto a high-speed steel substrate using the electroless nickel co-deposition method. The temperature and time were varied in a range of 300-400°C and 0-2 hours respectively. The microhardness measurements were carried out using a Vickers microhardness tester (Shimadzu) according to ISO 6507-4. The surface characterisation was analysed using Cambridge Stereoscan 90 Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray Analysis (EDXA). Findings: The optimum condition in obtaining high microhardness on Ni-YSZ cermet coating is evaluated by statistical tool ANOVA in Minitab20 software. It is found that the most significant parameter for high microhardness is at the treating temperature of 400°C followed by treating time at 2 hours using nano-sized YSZ particles. The ceramic particle size is found not a significant parameter in obtaining a high microhardness, however it has effect on interaction between treating temperature and treating time. Research limitations/implications: The paper only limits to the optimisation condition of microhardness on Ni-YSZ cermet coating hardness property by varying heat treatment parameters. Practical implications: The optimisation condition obtained might only applicable to the electroless Ni-YSZ cermet coating with similar electroless nickel solution and treatments. Originality/value: The value of this work is the heat treatment parametric optimisation to obtain high microhardness on electroless Ni-YSZ cermet coating by using the design of experiment 3-level full factorial.

4

Effect of heat treatment on microhardness of electroless Ni-YSZ cermet coating

Bahiyah Baba N., Ghazali A. S., Abdul Rahman A. H., Sharif S.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 113, nr 1

5--12

EN

Purpose: The paper discussed the effect of heat treatment on electroless nickel-yttria-stabilised zirconia (Ni-YSZ) cermet coating. Ni-YSZ cermet coating has potential applications such as cutting tools, thermal barriers, solid oxide fuel anode, and various others. The compatibility of ceramic YSZ and metallic nickel in terms of the mechanical properties such as hardness by varying the heating temperature, time and ceramic particle size is highlighted. Design/methodology/approach: Ni-YSZ cermet coating was deposited onto a highspeed steel substrate using the electroless nickel co-deposition method. The temperature and time were varied in a range of 300-400°C and 1-2 hours, respectively. The microhardness measurements were carried out using a Vickers microhardness tester (Shimadzu) according to ISO 6507-4. The surface characterisation of the cermet coating was carried out using JOEL Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray (EDX) JSM 7800F. The crystallographic structure of materials was analysed by X-ray diffraction (XRD) Bruker D8 Advance instrument. Findings: It was found that the microhardness of Ni-YSZ cermet coating with the ratio of 70:30, respectively, is directly proportional to the heating temperature and time. Heating the Ni-YSZ cermet coating at 300°C from room temperature (rtp) to 1 hour shows a 12% microhardness increment, while from 1 to 2 hours gives a 19% increment. Compared to heating at 350°C and 400°C, the increment is more significant at 33% and 49% for rtp to 1 hour and 8% and 16% for 1 to 2 hours, respectively. In addition, the effect of varying YSZ particle size in the Ni-YSZ cermet gave response differently for heating temperature and heating time. Research limitations/implications: The paper is only limited to the discussion of the heat treatment effect on Ni-YSZ cermet coating hardness property. The tribological effect will be in future work. Practical implications: The microhardness data may vary due to the Vickers microhardness force applied and the amount of ceramic particle incorporation and phosphorus content in the nickel matrix. Originality/value: The value of this work is the compatibility of the ceramic YSZ and metallic nickel matrix in terms of mechanical properties, such as hardness, upon heat treatment.

5

Laser Cladding of WC/T-800 Cermet: Fabrication, Microstructure and Wear Properties

Kim Kyoung-Wook, Kim Young-Kyun, Park Sun-Hong, Lee Kee-Ahn

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 3

713--717

EN

This study fabricated a WC/T-800 cermet coating layer with Co-Mo-Cr (T-800) powder and WC powder using laser cladding, and analyzed its microstructure, hardness and wear properties. For comparison, casted bulk T-800 was used. Laser cladded WC/T-800 cermet coating layer showed circular WC phases in the Co matrix, and dendritic laves phases. The average laves phase size in the cermet coating layer and bulk T-800 measured as 7.9 µm and 60.6 µm, respectively, indicating that the cermet coating layer had a relatively finer laves phase. Upon conducting a wear test, the cermet coating layer added with WC showed better wear resistance. In the case of laser cladded WC/T-800 cermet coating layer, abrasion wear was observed; on the contrary, the bulk T-800 showed pulled out laves phases. Based on the above findings, the WC/T-800 cermet coating layer using laser cladding and the relationship between its microstructure and wear behavior were discussed.

6

High-Velocity Impact of 2-Phase WC/Co Composite Plate - Beginning of the Process

Postek E., Sadowski T.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 1

265--274

EN

2-phase composites are often used for high demanding parts that can undergo impact loads. However, most of the papers on dynamic loading concerns layered composites. In our opinion, the impact loads are not considered thoroughly enough. Good examples of 2-phase composites are: (1) a WC/Co cermet or (2) a monolithic ceramic Al2 O3 /ZrO2 . The WC/Co cermet is often modelled as having ductile elasto-plastic Co matrix and ideally elastic WC grains. It is because of very high crushing resistivity of the WC. In this paper, we present an extension to earlier elaborated models ([44]) with the assumption of ideal elasticity of the grains. The new and general numerical model for high-velocity impact of the 2-phase composites is proposed. The idea of this novelty relies on the introduction of crushability of grains in the composite and thermo-mechanical coupling. The model allows for description of the dynamic response both composite polycrystals made of: (1) 2 different purely elastic phases (e.g. Al2 O3 /ZrO2 ) or (2) one elastic phase and the second one plastic (e.g. cermet WC/Co), or (3) 2 elasto-plastic phases with different material properties and damage processes. In particular, the analysis was limited to the cases (2) and (3), i.e. we investigated the WC/Co polycrystal that impacted a rigid wall with the initial velocity equal to 50 m/s.

7

Wear resistance of the cermet cutting tools after aluminum (Al+) and nitrogen (N+) ion implantation

Morozow D., Narojczyk J., Rucki M., Lavrynenko S.

Advances in Materials Science

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2018

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Vol. 18, nr 2(56)

92--99

EN

In the paper, the issue of the cermet cutting tools wear resistance was addressed. The tool inserts made out of cermet composites were exposed to the ion implantation with ions of nitrogen N+ and with combination of nitrogen N+ and aluminum Al+ ions. In order to assess the impact of the ion implantation, the samples of stainless steel EZ6NCT25 were turned with the standard cutting tools and with the inserts after ion implantation. The results in general confirmed better wear resistance of the ion implanted inserts. In particular, they performed 20-40% smaller friction. After some time, when the destruction of the implanted surface layer took place, the friction coefficient rose up to the value typical for non-implanted inserts. For the implanted inserts, the wear index VB appeared to be lower, and even visual assessment revealed distinguishably smaller wear than in case of tools without ion implantation.

8

Struktura i odporność na zużycie tribologiczne powłok z cermetalu na stali S275N

Lis A., Lis J., Kolan C., Wieczorek P.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 4

1064-1067

PL

Badano mikrostrukturę natryskiwanego cieplnie proszku MetaCeram 28020 na powłoce pośredniej NiAl na stali S275N. Przedstawiono rozkład pierwiastków stopowych w powłoce oraz zmiany twardości. Przyczepność powłoki została stwierdzona do obciążenia ~140 N. Zmierzono zmiany współczynnika tarcia i siły tarcia oraz profilu głębokościowego i resztkowego w funkcji obciążenia. Stwierdzono zużycie tribologiczne na próbce wynoszące 0,00144 g i na przeciwpróbce 0,00174 g. Przedstawiono zmiany współczynnika tarcia i głębokości wytarcia z upływem czasu w warunkach smarowania olejem przekładniowym GL-4. Zamieszczono mikrofraktografie powierzchni po tribologicznym zużyciu.

EN

Microstructure of MetaCeram 28020 powder spraying cermet on sublayer NiAl on S275N steel was investigated. The chemical distribution of alloying elements in the coating were studied. Increased hardness of outer coating layer was measured. Coating adhesion was satisfied at load up to 140 N. Effect of load in friction coefficient and differences in penetration depth and residual depth were measured. Good resistance to abrasive wear was established from mass decreament after wear on specimen as 0,00144 g and roll counter specimen 0,00174 g. The changes of friction coefficient and depth of the wear traces with time for condition of smearing with gear oil GL-4 were described. Microfractography of surface after tribological wear was presented.

9

Problemy lutowania spieków ceramiczno-metalicznych i stali na dużych powierzchniach

Nowacki J.

Przegląd Spawalnictwa

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2009

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R. 81, nr 5

32-37

PL

Artykuł dotyczy problemów wytwarzania odpornej na ścieranie warstwy na powierzchni dużych rozmiarów w wyniku pokrycia jej płytkami spieków cermetalicznych. Płytki zostały przylutowane próżniowo do stali nierdzewnej utwardzanej wydzieleniowo. Analizowano wpływ parametrów geometrycznych szczeliny lutowniczej na mikrostrukturę, właściwości i jakość złącza. Zdefiniowano główne czynniki ograniczające możliwość wytworzenia wysokiej jakości złącza w procesie lutowania próżniowego.

EN

The article concerns the problems of manufacturing of the abrasion-resisting layer on a large size surface as a result of its covering with plates of cermets. The plates were soldered to the precipitation hardened stainless steel using the vacuum soldering process. Effect of soldering gap geometric parameters on microstructure, properties and joint quality were analysed. The main factors which limit possibilities of making of the high quality joint in the vacuum soldering process were defined.

10

Mechanochemical synthesis of nanocrystalline cermets

Wieczorek-Ciurowa K., Gamrat K.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 3

51-53

EN

The formation of cermet consisting of Cu(Al) solid solution and aluminium oxide was discussed. The composite synthesized by high-energy ball milling carried out in a laboratory planetary mill. Salt and active metal, Cu-hydroxycarbonate and powdered aluminium, were used as the starting materials. Phase analysis of the mechanochemically synthesized product was carried out on the basis of X-ray diffractometry and thermal analysis methods.

11

Gradient coatings deposited by Cathodic Arc Evaporation: characteristic of structure and properties

Dobrzański L. A., Gołombek K.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 14, nr 1-2

48--53

EN

Purpose: It has been demonstrated in the paper that deposition of the multilayer and gradient coatings with the PVD method in the Cathodic Arc Evaporation CAE process on tools made from cermets. Design/methodology/approach: Structural examinations are presented of the applied coatings and their substrate made on the TEM, SEM and on the light microscope. Evaluation of the adhesion of the deposited coatings onto the cermets was made using the scratch test. Cutting properties of the investigated materials were determined basing on the technological continuous cutting tests of the C45E steel. Microhardness tests of the deposited coatings were made on the ultra-micro-hardness tester. Surface roughness tests were also made before depositing the coatings and after completing the PVD process. Findings: It has been demonstrated in this work that deposition of the TiN+(Ti,Al,Si)N+TiN multilayer or gradient coatings with the PVD (Cathodic Arc Evaporation) process on tools made from cemented carbides, results in the increase of coatings’ hardness and improvement of their adhesion to the substrate, in comparison with the multiple-layer coatings deposited using the PVD method on the same substrate materials, deciding improvement of the working properties of cutting tools coated with the TiN+gradient or multi(Ti,Al,Si)N+TiN system coatings, compared with coatings developed on the same sintered tool materials, but uncoated or coated with simple coatings. Practical implications: Gradient coatings deposited with the CAE method onto the cermet substrate qualify for the widespread industrial use on cutting tools and offering the possibility to use them in the pro-ecological dry cutting processes without the use of the cutting fluids and in the „Near-Net-Shape” technology. Originality/value: In the paper the research of newly worked out multilayer and gradient TiN+(Ti,Al,Si)N+TiN nanocrystalline coatings deposited in the PVD method on cermets carried out in order to improve the tool cutting properties. To explain reasons of significant improvement of tool exploitation properties modern material science methods of research especially of the one of thin foils including those on cross-sections on a high-voltage transmission electron microscopy have been used. As a result of very complicated and difficult preparation methods, similar research are made only by few, the most advanced in the world, laboratories of electron microscopy, but concerning other coatings on other substrates than those analysed in the given paper. Undoubtedly, using such modern research methods is a modern approach to the solution and explanation of the scientific problem presented in that paper.

12

The microstructure and properties forming sintered M35 HSS base cermets

Indra J., Leżański J.

Kompozyty

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2005

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R. 5, nr 1

79-84

EN

In this paper the manufacturing process and properties of sintered M35 high speed steel with addition of tungsten carbide WC cermets have been studied. The chemical composition of M35 steel is presented in Table 1. Morphology of powder particles M35 steel and tungsten carbide WC are shown in Figure 1. The raw powders were mixed together in a ceramic mortar for 60 minutes. The following composition was investigated: M35+10 wt.% WC. Cold compacting in a rigid, rectangular die at 800 MPa was followed by sintering in vacuum furnace at six different temperatures in the range 1150-1220°C under vacuum pressure below 10(-2) Pa. The sintering process assembled with three stages: annealing at 950°C for 30 minutes, isothermal sintering for 60 minutes and cooling with furnace. The as-sintered specimens were subjected to density and microhardness measurements. Density was measured on the base of Archimedes' law. Figure 2 shows the results of density of sintered M35+10 wt.% WC cermets. For the micro-hardness measurement Hanemann harness testing machine was used. For microstructure examination light and SEM microscopy techniques were employed. Diffractometer TOR M62 with HZG4 goniometer was employed for X-ray diffraction analysis. On the base of results and microstructure observation it may be concluded that the processing parameters and tungsten carbide content simultaneously affect the as-sintered properties of the investigated cermets.

PL

Przedstawiono wyniki badań spiekanych węglikostali na osnowie stali szybkotnącej typu M35 z dodatkiem węglika wolframu WC. Skład chemiczny stali M35 przedstawiono w tabeli 1. Morfologie cząstek proszku stali M35 i węglika wolframu WC pokazano na rysunku 1. W wyniku ucierania proszków w ceramicznym ścieraku moździerzowym przez 60 minut wytworzono mieszanki o składzie M35+10% WC. Mieszanki proszków prasowano w prostopadłościennej matrycy stemplem od góry pod ciśnieniem 800 MPa. Kształtki spiekano w próżni poniżej 10(-2) Pa w temperaturze od 1150 do 1220°C. Proces spiekania składał się z trzech etapów: wyżarzania w 950°C przez 30 minut, izotermicznego spiekania przez 60 minut oraz chłodzenia z piecem. Przeprowadzono badania gęstości, mikrotwardości oraz składu fazowego spiekanych weglikostali. Pomiar gęstości spiekanych weglikostali wykonano metodą wykorzystującą prawo Archimedesa, a wyniki przedstawiono na rysunku 2. Badanie mikrotwardości przeprowadzono za pomocą mikrotwardościomierza Hanemanna. Obserwacje mikrostruktury wykonano za pomocą mikroskopów świetlnego oraz skaningowego. Rentgenowską analizę fazową spiekanych węglikostali wykonano z pomocą dyfraktometru TUR M62 z goniometrem HZG4. Na podstawie analizy otrzymanych wyników stwierdzono, że dodatek węglika wolframu WC oraz zmiana parametrów wytwarzania pozwalają na kształtowanie w szerokim zakresie właściwości oraz mikrostruktury spiekanych węglikostali.

13

Examination of surface characteristics in tribological systems by AFM

Zdravecka E., Suchanek J., Lubiščak J., Greškovič F., Spišak E.

Tribologia

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2002

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nr 6

1713-1722

EN

The large group of thermally sprayed coatings is suitable for increasing of abrasive wear resistance. Tribological behaviour of 5 types of these coatings were tested with RWAT tester. Thermally sprayed coatings prepared with HP/HVOF - SKODA Research s.r.o. Plzeň and US STEEL Košice methods were examined with REM, optical microscopy, AFM and the measurement of microhardness HVM.

PL

Powłoki uzyskiwane w procesie natryskiwania cieplnego coraz częściej znajdują zastosowanie do zwiększania odporności na zużycie cierne. Tribologiczne właściwości pięciu rodzajów materiałów powłok zostały zbadane za pomocą maszyny RWAT. Powłoki uzyskano metodą HP/HVOF w firmach SKODA Plezen i US STEEL Kosice. Wykonano badania z użyciem techniki REM, mikroskopii optycznej oraz wykonano pomiary mikrotwardości HVM.