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1

Phenomenological model of cavitation erosion of nitrogen ion implanted HIPed Stellite 6

Szala Mirosław

Advances in Materials Science

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2023

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Vol. 23, nr 1(75)

98--109

EN

Stellites are a group of Co-Cr-C-W/Mo-containing alloys showing outstanding behavior under cavitation erosion (CE) operational conditions. The process of ion implantation can improve the CE resistance of metal alloys. This work presents the elaborated original phenomenological model of CE of nitrogen ion implanted HIP-consolidated (Hot Isostatically Pressed) cobalt alloy grade Stellite 6. The ultrasonic vibratory test rig was used for CE testing. The nitrogen ion implantation with 120 keV and fluence of 5 × 1016 N+/cm−2 improves HIPed Stellite 6 cavitation erosion resistance two times. Ion-implanted HIPed Stellite 6 has more than ten times higher CE resistance than the reference AISI 304 stainless steel sample. Comparative analysis of AFM, SEM and XRD results done at different test intervals reveals the kinetic of CE process. The model includes the surface roughness development and clarifies the meaning of cobalt-based matrix phase transformations under the nitrogen ion implantation and cavitation loads. Ion implantation modifies the cavitation erosion mechanisms of HIPed Stellite 6. The CE of unimplanted alloy starts on material loss initiated at the carbides/matrix interfaces. Deterioration starts with cobalt matrix plastic deformation, weakening the carbides restraint in the metallic matrix. Then, the cobalt-based matrix and further hard carbides are removed. Finally, a deformed cobalt matrix undergoes cracking, accelerating material removal and formation of pits and craters' growth. The nitrogen ion implantation facilitates ɛ (hcp—hexagonal close-packed)) → γ (fcc—face-centered cubic) phase transformation, which further is reversed due to cavitation loads, i.e., CE induces the γ → ɛ martensitic phase transformation of the cobalt-based matrix. This phenomenon successfully limits carbide removal by consuming the cavitation loads for martensitic transformation at the initial stages of erosion. The CE incubation stage for ion implanted HIPed Stellite 6 lasts longer than for unimplanted due to the higher initial content of γ phase. Moreover, this phase slows the erosion rate by restraining carbides in cobalt-based matrix, facilitating strain-induced martensitic transformation and preventing the surface from severe material loss.

2

The Impact of Material Selection on Durability of Exhaust Valve Faces of a Ship Engine – A Case Study

Smoleńska Hanna, Kończewicz Włodzimierz, Bazychowska Sylwia

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 3

165--174

EN

Two alloys were used in order to extend the service life of marine engine exhaust valve head. Layers of cobalt base alloys were made of the powders with chemical composition as follow: the layer marked L12; C-1.55%; Si-1.21%; Cr-29.7%; W-9%; Ni-2%; Mo<0.01%; Fe-1.7%; Co-54.83% and the layer marked N; C-1.45%; Co-38.9%; Cr24.13%; Ni-10.43%; W-8.75%; Fe-7.64%; Mo-7.56%; Si-2.59%. Base metal was valve steel after heat treatment. It was consisted of: C-0,374%; Cr-9,34%; Mn-0.402%; Ni-0.344%; Si-2.46%; Mo-0.822%; P-0.0162%; S-0.001%. Layers on the valve faces were produced by laser cladding using the HPDL ROFIN DL020 laser. Grinding treatment is a very popular form of regeneration of seat and valve plug adhesions. Properly performed grinding operation ensures dimensional and shape accuracy of the surface from 7 to 5 accuracy class and surface roughness Ra not less than 0.16 μm, depending on the object and method of grinding. The 75H and 150S types are a significantly simplified form of valve plug face grinders. Finishing treatment was carried out with a Chris-Marine AB75H sander on a sanding stand equipped with a compressed air system - the stand was designed by the author. The sander has been set up to the surface of the valve stem so that the grinding angle of the valve faces is 30°+10°. A flat grinding wheel T1CRA54–K was used for machining. The plunge feed was 0.01 mm/rev. The thickness of the welded layer after grinding was 1.2 mm. Both valves were installed in the ship’s engine and were used in real life. After 2000 hours of operation, the valve marked N was damaged. The valve marked L12 showed no damage and was in operation for the next 1000 hours.

3

Comparing of Microhardness of the Stellite 6 Cobalt Alloy Implanted with 175 keV Mn+ Ions and 120 keV N+ Ions

Kamiński Mariusz, Budzyński Piotr, Szala Mirosław, Turek Marcin

Advances in Science and Technology. Research Journal

|

2019

|

Vol. 13, no 3

179--185

EN

Nowadays, high-precision machines require lightweight materials with very high strength. Ion implantation is used to improve the mechanical strength of the material. A further paper presents the influence of manganese and nitrogen ion implantation on changes of microhardness of the surface layer of cobalt alloy. Samples were analyzed with the SEM-EDS Phenom ProX microscope. Microhardness was assessed with the Vickers method, and the loads of 1 gf (0.00981 N) and 5 gf (0.049 N) was applied using a FM-800 from Future-Tech microhardness meter. At a load of 1 gf, the penetration depth of the implanted specimens was reached not exceeding 0.5 um. At this depth, all samples showed an increase in microhardness compared to the unimplanted sample. The highest increase in microhardness was achieved after implantation of Mn ions with dose D=1∙1017 Mn+/cm2 and energy E=175 keV. The increased load on the indenter to 5 gf reduced the microhardness differences between implanted and unimplanted samples.

4

Possibilities of production of the composite coatings reinforced by hard ceramic particles by laser cladding

Bartkowski D., Dudziak B., Piasecki A., Matysiak W.

Journal of Research and Applications in Agricultural Engineering

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2015

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Vol. 60, nr 2

17--20

EN

The paper presents research results of metal matrix composite coatings produced on S355 steel using laser cladding. Two powder mixtures Stellite-6/30% B4C and Stellite-6/30% SiC were used. The aim of this study was to determine the applicability of these materials in the production of composite coatings having a microstructure similar to sintered carbides. Applied carbides were characterized by very high hardness (B4C -3800 HV, SiC -2500 HV) and a high melting point (B4C -2763°C, SiO -2730°C).Such parameters are conducive to formation of coatings with composite microstructure. The purpose of analyzed process consisted in complete melting of matrix material, partial melting of reinforcing particles and minimal melting of substrate material. This effect has been achieved to a limited extent.

PL

Przedstawiono wyniki badań kompozytowych warstw powierzchniowych wytwarzanych na stali S355przy użyciu proszkowego napawania laserowego. Zastosowano dwie mieszaniny proszkowe Stellite-6/30%B4C oraz Stellite-6/30%SiC.Celem badań było określenie możliwości zastosowania tego rodzaju materiałów do wytwarzania kompozytowych warstw powierzchniowych o mikrostrukturze zbliżonej do węglików spiekanych. Zastosowane węgliki charakteryzowały się bardzo dużą twardością (B4C -3800 HV, SiC -2500 HV) oraz wysoką temperaturą topnienia (B4C -2763°C, SiC -2730°C). Takie parametry sprzyjają wytworzeniu warstwy o budowie kompozytowej. Celem badanego w pracy procesu było całkowite przetopienie materiału osnowy, częściowe cząstek fazy wzmacniającej oraz minimalne materiału podłoża. Efekt ten został osiągnięty w ograniczonym zakresie.

5

Microstructure and wear resistance of Stellite-6/WC metal matrix composite coatings

Bartkowski D., Kinal G., Dudziak B., Piasecki A., Matysiak W.

Journal of Research and Applications in Agricultural Engineering

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2015

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Vol. 60, nr 2

21--25

EN

The paper presents the study results of metal matrix composite coatings formed on S355 and B27 steels by laser cladding with powder technology. Powder mixture consisting of cobalt based alloy and tungsten carbides particles was used. The study consisted of production of the coatings using Trumpf TruDisk laser device equipped with 3-stream nozzle powder feeding system. Composite coatings were produced both on laboratory specimens as well as on agricultural tools. The constant value of feed rate equals 460 mm min-1 and different values of laser beam power (400, 550 and 700 W) have been used. The influence of laser beam power on microstructure, chemical composition and wear resistance on produced coatings have been investigated.

PL

Przedstawiono wyniki badań z kompozytowych warstw powierzchniowych wytwarzanych na stalach S355 i B27 przez napawanie laserowe techniką proszkową. Zastosowano mieszaninę proszkową składającą się z proszku stopu na bazie kobaltu i cząstek węglika wolframu. Badanie polegało na wytworzeniu warstw powierzchniowych przy użyciu urządzenia laserowego Trumpf TruDisk wyposażonego w system trójstrumieniowego podawania proszku. Warstwy powierzchniowe wytwarzano zarówno na próbkach laboratoryjnych jak i na narzędziach rolniczych. Zastosowano stałą wartość posuwu wiązki lasera równą 460 mm min-1 oraz różne wartości mocy wiązki (400, 550 i 700 W). Badano wpływ mocy wiązki lasera na mikrostrukturę, skład chemiczny i odporność na zużycie przez tarcie wytworzonych warstw powierzchniowych.

6

The Influence of Remelting on the Quality of Prosthetic Cobalt Alloys

Nadolski M., Łągiewka M., Konopka Z., Zyska A., Golański G.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 3 spec.

53--58

EN

A commercial cobalt alloy applied in dental prosthetics was investigated. The scope of the work included the microstructure analysis, performance examination (tensile strength, microhardness, corrosion resistance), and dilatometric examination. The investigated alloy after a single remelting was characterised by higher tensile strength and hardness. There were not found the definite results with regard to the corrosion resistance of the examined materials. No significant change occurred in the coefficient of thermal expansion.

7

Struktura i własności materiałów kompozytowych magnetycznie miękkich o osnowie silikonowej wzmacnianych nanokrystalicznymi proszkami stopu kobaltu

Konieczny J.

Przetwórstwo Tworzyw

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2014

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[R.] 20, nr 2 (158)

182--186

PL

W artykule przedstawiono wyniki badań mikrostruktury, własności mechanicznych i magnetycznych materiałów kompozytowych, magnetycznie miękkich o osnowie silikonowej. Proszki metalowe otrzymano w wyniku mielenia taśm metalowych o strukturze amorficznej oraz nanokrystalicznej ze stopu Co68Fe4Mo1B13,5Si13,5. Wykazano, że na własności mechaniczne jak i fizyczne bardzo silnie oddziałuje udział metalowego proszku.

EN

The article presents the investigation results of microstructure, mechanical and magnetic properties of soft magnetic composite materials with silicone matrix. Metal particles obtained by high energy ball milling of the metal ribbons of amorphous and nano-crystalline structure of the alloy Co63Fe4Mo1B13,5Si13,5. It was shown that the mechanical properties as well as physical influences strongly the powder metal part.

8

Co-based alloy surface layers with boron carbide particles produced on S235 steel by laser cladding method

Bartkowski D., Dudziak B., Piasecki A., Gościański M.

Journal of Research and Applications in Agricultural Engineering

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2014

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Vol. 59, nr 1

12--16

EN

The work presents results of study of the surface layers formed during the laser cladding process with powder mixture of Co-based alloy and B4C particles on S235 steel. The study included production of the surface layers by using laser device equipped with three-stream nozzle powder feeding system. The different feed rate and the same value of laser beam power have been used. The influence of powder morphology on efficiency of laser metal deposition as well as influence of B4C additive on microhardness, microstructure and chemical composition of produced surface layers have been investigated.

PL

W pracy przedstawiono wyniki badań warstw powierzchniowych wytworzonych przez napawanie laserowe mieszaniny proszkowej stopu na bazie kobaltu i cząstek węglika boru B4C na stali S235. Badania obejmowały wykonanie warstw powierzchniowych przy użyciu urządzenia laserowego wyposażonego w dyszę z trójstrumieniowym systemem podawania proszku. Zastosowano różne prędkości posuwu wiązki lasera przy jednakowej wartości mocy. Stwierdzono, że rodzaj morfologii proszku ma wpływ na wydajność procesu napawania. Określono wpływ dodatku węglika boru na twardość, mikrostrukturę i skład chemiczny wytwarzanych warstw powierzchniowych.

9

Osadzanie elektroforetyczne polimerowych powłok chitozanu na biomateriałach metalowych

Jugowiec D., Radziszewska A., Kot M., Moskalewicz T.

Engineering of Biomaterials

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2014

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Vol. 17, no. 128-129

16--19

PL

Powłokę chitozanu osadzono metodą elektroforezy na stopie tytanu Ti13Zr13Nb i stopie kobaltu Co28Cr-5Mo. W obecnej pracy skoncentrowano się głównie na doborze parametrów osadzania elektroforetycznego w celu otrzymania jednorodnych i ciągłych powłok chitozanu na biomateriałach metalowych. Stwierdzono, że jednorodność wytworzonych powłok istotnie zależała od rodzaju zastosowanego roztworu i parametrów osadzania. Mikrostrukturę materiałów podłoży oraz powłok zbadano za pomocą mikroskopii świetlnej oraz skaningowej- i transmisyjnej mikroskopii elektronowej. Zmierzono twardość i moduł Younga materiałów podłoży. Wykonano badania przyczepności powłok do podłoży stopu tytanu i stopu kobaltu.

EN

A chitosan coatings were electrophoretically deposited (EPD) on the Ti13Zr13Nb and Co28Cr5Mo alloys. The main aim of this work was to find optimal EPD parameters to obtain homogeneous and continuous coating on metallic biomaterials. It was found that the homogeneity of the as-deposited chitosan coatings on the substrate materials is highly dependent on chosen solution and EPD parameters. The microstructure of the substrate materials and coatings were investigated by light microscopy as well as scanning- and transmission electron microscopy. The hardness and Young’s modulus of the alloys as well as adhesion of chitosan coatings to the substrate materials were investigated.

10

Cohesion and Adhesion Interlayer of the Thermal Barrier Coatings Made of Cobalt Alloy MAR-M509

Opiekun Z. A., Trytek A.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 1 spec.

159--164

EN

The manuscript presents microstructure, geometrical product specification and results of scratch tests performed on the interlayer of thermal barrier coating (TBC) with Rockwell’s intender. The TBC was provided by depositing two layers; metallic interlayer and external ceramic layer onto a plate coating made of cobalt alloy MAR-M509 in plasma spraying process. The surface of the casting was sandblasted with Al2O3 powder in an air stream before the TBC was introduced. Scratches were made along the cross-section from a mould material (MAR-M509) through metallic interlayer and external ceramic layer in the TBC. Friction force, friction factor and acoustic emission were recorded during the test. It has been proved that metallic interlayer in the TBC of ca. 200 μm thickness forms tough coating without pores with good cohesion values and very good adhesion values to the mould.

11

Wpływ technologii wytwarzania na właściwości materiałowe stopu kobaltu wykorzystywanego w protetyce dentystycznej

Litwinko M., Grądzka-Dahlke M.

Aktualne Problemy Biomechaniki

|

2014

|

z. 8

99--102

PL

Jednym z etapów w procesie powstawania protetycznego uzupełnienia dentystycznego jest realizacja zaprojektowanego kształtu protezy w tworzywie metalowym. Jest krokiem istotnym a zarazem narażonym na wiele niepowodzeń. W artykule przedstawiono porównanie dwóch metod wykonawstwa techniki dentystycznej: tradycyjnego odlewania oraz nowoczesnej SLM. Badaniom poddano protetyczny stop kobaltu w postaci prostopadłościennych próbek.

EN

One of the stages in the process of restoration of dental prostheses is the shape which was designed to achieve a complement in the metal. It is an important step and exposed to many setbacks. The article gives a comparison of two methods of dental technology: traditional casting and modern SLM. The test was in the form of a cobalt alloy prosthetic square bales samples.

12

Influence the heat treatment of two base metal alloys used on dental prosthesis on corrosion resistance

Reimann Ł., Dobrzański L.A., Nieradka B., Kusy M., Riedlmajer R.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

|

Vol. 57, nr 2

83--90

EN

Purpose: The goal of the study is to try find the influence of the heat treatment on the corrosion resistance of two base cobalt alloys used on dental prosthesis. Design/methodology/approach: The investigation was choosen two base cobalt alloys: Remanium 2000+ (Dentaurum) and Wirobond LFC (Bego). Corrosion resistance test were carried out at room temperature and use of the Potentiostat IPS AJ PGU system for electrochemical tests. The examination use of water center which simulated artificial saliva environment. The evaluation of pitting corrosion was realized by recording of anodic polarization curves with use the potentiodynamic methods. Structure observation was made after surface preparation by light microscope. Findings: Research cobalt alloys are characterized by a dendritic crystals in structure. For both cobalt alloys increasing the time of age hardening effect on growth of the corrosion resistance, especially to increase the potential for pitting initiation. Research limitations/implications: The research was carried out on samples, not on final elements. Practical implications: The research material is used on dentures, so it must characterize the corrosion resistance. Results of this work make up an information on what heat treatment parameters may be pay attention for two base cobalt alloys: Remanium 2000+ (Dentaurum) and Wirobond LFC (Bego). Originality/value: The paper presents influence the heat treatment of two base metal alloys used on dental prosthesis on corrosion resistance.

13

Zachowanie korozyjne stopów kobaltu w roztworze sztucznej śliny

Loch J., Krawiec H.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3 spec.

101--106

PL

Stopy kobaltu są materiałami wykorzystywanymi w medycynie oraz stomatologii ze względu na swoje idealne połączenie dobrych właściwości wytrzymałościowych, korozyjnych oraz biokompatybilność. Obecnie stopy kobaltu są jednymi z najbardziej atrakcyjnych materiałów metalowych, używanych do wyrobu implantów w tym: sztucznych stawów biodrowych, kolanowych, dysków miedzykręgowych, śrub zabezpieczających złamania. W stomatologii wykonuje się z nich wszelkiego rodzaju wkręty, stanowiące podstawę do przytwierdzania zębowych protez ceramicznych. Ze względu na powszechne wykorzystanie stopów kobaltu w stomatologii, w pracy podjęto badania elektrochemiczne wybranych stopów kobaltu: Co-Cr-Mo i Co-Cr-W, których celem było określenie właściwości korozyjnych podczas ekspozycji w fizjologicznym roztworze sztucznej śliny, w temperaturze 37 °C, pH = 8,3 i swobodnym dostępie tlenu.

EN

Cobalt alloys are used in medicine and dentistry due to perfect combination of their high strength, corrosion resistance and biocompatibility. Currently, cobalt alloys are among the most attractive metallic materials used to manufacture such implants as artificial hip joints, knee joints, intervertebral discs, screws securing the fracture. All kinds of screws used in dentistry for basic fixing of ceramic dental prostheses are made from cobalt alloys. Widespread use of cobalt alloys in dentistry is the reason for electrochemical research on selected cobalt alloys (Co-Cr-Mo and Co-Cr-W). The aim of the research was to determine the corrosion when the alloy is exposed to physiological artificial saliva solution at the temperature of 37 °C, pH = 8.3 and in aerated solution.

14

Metallographic analysis of selected cobalt-based alloys with carbon additive

Woźna A.

Aktualne Problemy Biomechaniki

|

2011

|

z. 5

177--184

EN

In this paper an analysis of the microstructure of cobalt-based alloys used for implants with different chemical composition was held. Metallographic analysis was conducted using the methods of light microscopy and scanning electron microscopy. Characterization and description of the phases occurring in the investigated alloys was carried out using X-ray microanalysis, X-ray diffraction analysis and hardness measurements. The aim of this study was to determine the nature of the structure, chemical composition and its selected properties that affect their use application.

15

Materiały stopowe kobalt-pallad

Zieliński M.

LAB Laboratoria, Aparatura, Badania

|

2010

|

R. 15, nr 2

14-18

16

Elektrochemiczna redukcja stopów kobalt-pallad

Zieliński M.

LAB Laboratoria, Aparatura, Badania

|

2010

|

R. 15, nr 1

11-14

17

Investigation of selected thermo-physical properties in the Co-based superalloy: Experiment and application study

Kasala J., Mäsiar H., Pernis I.

Archives of Foundry Engineering

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2010

|

Vol. 10, iss. 1 spec.

203--206

EN

Thermo-physical properties are the critical input parameters in computational models of solidification and casting simulations. In thermodynamics, the enthalpy is quotient of thermodynamic potential of a system, which can be used to calculate the useful work obtainable from a closed thermodynamic system under constant pressure. Differential thermal analysis has been used to study melting and solidification paths in the cobalt based superalloy FSX-414. The temperature enthalpy curve was determined from differential thermal analysis curves obtained from solidification curves. A solidification simulation of a cobalt base multi-component alloy casting was carried out to predict cooling and shrinkage porosity in the casting of a turbine engine vane segment. The effect of latent heat on the heat transfer calculation was considered by enthalpy method.

18

Structural studies of partial meltings of casting surfaces made of cobalt alloy MAR-M509

Opiekun Z., Chruściel K.

Archives of Foundry Engineering

|

2009

|

Vol. 9, iss. 2

197-200

EN

The results of structural studies of partial meltings of casting surfaces of plates made of cobalt alloy MAR-M509 have been presented. The partial meltings were formed with argon or helium plasma beam generated in electric arc. Observations of microstructure revealed presence of phase y and carbides. X-ray diffraction has shown phase y, carbide types MC and M23C6 and scanty amount of hexagonal phase [...].

19

Geometričeskaâ struktura poverhnosti otlivok iz žaropročnyh splavov na osnove kobal'ta

Lubimov V., Opekun Z., Bonk S.

Archives of Foundry Engineering

|

2007

|

Vol. 7, iss. 1

113-116

EN

Geometrical product specification MAR-M509 cast cobalt alloy depend beginning temperature of multilayer ceramic shell moulds (MCS). It has found that go down temperature of MCS from 1000°C to 200°C, the increase surface roughness and its amplitude parameters: Sa, Sz, St, Sq, Sp and Sv.

20

Morfologia napawanych warstw na bazie kobaltu po utlenianiu i korozji w gazach spalinowych

Smoleńska H.

Problemy Eksploatacji

|

2006

|

nr 1

115-121

PL

Przedmiotem badań były warstwy wytworzone z proszku na bazie kobaltu, napawane laserowo i plazmowo na przylgnie zaworów wylotowych silników Diesla. Dla wszystkich warstw stwierdzono dobrą jakość, brak pęknięć i jednorodność struktury na powierzchni. Badania degradacji wykonano w specjalnie wykonanej komorze w gazach spalinowych silnika okrętowego. Badania napoin przeprowadzono po 2 miesiącach ekspozycji w podwyższonej temperaturze w zakresie 600-800°C lub po utlenianiu w powietrzu w temperaturze 650°C przez 100 godzin.

EN

Cobalt base cladding layers on the exhaust valve head face, produced by laser and PTA cladding have been investigated. For the all sort of layers good quality, lack of cracks and proper microstructure for the top part of clad was obtained. The investigations on the degradation process run on the special chamber in the exhaust gases of the ship diesel engine. The layers were exposed for two month for the exhaust gases at elevated temperature 600-800°C and after oxidation in air at temperature 650°C for 100 hours. The chemical and phase composition of the scale were determined.