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Effect of Shot Peening Parameters on Surface Properties and Corrosion Resistance of 316L Stainless Steel

Walczak Mariusz, Matijošius Jonas, Özkan Doğuş, Pasierbiewicz Kamil

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

296--304

EN

The present work deals with the enhancement of the surface characteristics of stainless steel 316L as a result of shot peening treatment using ceramic balls. In accordance with our own research and information available in literature, as a result of shot peening process, the shot balls can penetrate to the surface layer (permanently depositing) and modify the mechanical performance and the corrosion resistance in the products being treated in this way. Shot peening leads to a significant change to the surface hardness and topography, and consequently, to the change in corrosion behaviour dependent on the choice of processing parameters. Therefore, in this paper, steel samples were treated using two variable parameters of peening pressure (0.3 and 0.4 MPa) and peening time (30 and 60s). In the research, the reference surface were the samples subjected to mechanical polishing. The surface morphology of the samples was investigated by scanning electron microscopy (SEM). The potentiodynamic polarization tests were performed with 1 mV/s scan rate in 0.9% NalCl solution. The improved corrosion resistance (lowest current density Icorr=0.35µA/cm2 and highest corrosion potential Ecorr=-0.164V) was obtained for specimens with longer time (60s) and higher pressure of shot peening treatment (0.4MPa). Greater changes in surface roughness were observed with an increase in peening pressure than with an increase in the processing time. The treatment of the surface with ceramic shots results in an increase in the hardness of the treated surface by more than 110% (for sample 316L/0.4/60) compared to the reference surface. Moreover, an increase in average hardness values was recorded for all surfaces after shot peening (by more than 42% relative to reference samples).

2

Investigations of corrosion behaviour of SnSb12Cu6Pb alloy in 0.1M H2SO4 and 0.5M NaCl solution

Hrabia-Wiśnios J., Leszczyńska-Madej B., Kowalik R.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 101, nr 1

5--14

EN

Purpose: The results presented the microstructure and corrosive behavior of SnSb12Cu6Pb alloy (B82) in H2SO4 aqueous solution and NaCl aqueous solution. Design/methodology/approach: The electrochemical corrosion has been investigated in two different aqueous solutions: 0.1M sulfuric acid (H2SO4) and 0.5M sodium chloride (NaCl) solution measuring of potential changes relative to immersion time and conducting mass loss test. Microscopic investigations before and after corrosion tests were made using scanning electron microscopy. Findings: The obtained results indicate very good corrosion resistance of the alloy tested in NaCl solution. Corrosion progresses faster in a sulfuric acid aqueous solution compared to sodium chloride aqueous solution. Also, it was found that the dominant mechanism of corrosion degradation in both solutions is selective corrosion which is a particularly undesirable type of corrosion because it involves the loss of one alloying component and the formation of porous structure on the alloy surface. Research limitations/implications: The aqueous solutions used in this study are not a natural working environment of the bearing. However, a comparison of acidic and neutral solutions allows explaining the corrosion behavior of tin babbitts due to contaminants of oil lubricants. Further research should be conducted in more aggressive environments characteristic of industrial conditions. Practical implications: One of the important properties of bearing alloys are corrosion resistance. Corrosion properties are extremely important for the transport and storage of metallic components before they are used. Also, the working environment can have a destructive effect on the properties of the materials used. Industry environment, aging stagnant oil, and some acids may lead to selective corrosion of the tin, copper, lead, or antimony components and leaving a rough and weakened the babbitt surface. Electrochemical corrosion can contribute to the acceleration of bearing wear and consequent to bearing damage. Originality/value: Studies of the corrosion of tin-babbitt bearings are not extensive in the literature due to rare tin corrosion. This study could be an important complement to knowledge about the corrosion behavior of tin-based bearing alloys.

3

The effect of shot peening on the corrosion behaviour of Ti-6Al-4V alloy made by DMLS

Żebrowski R., Walczak M.

Advances in Materials Science

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2018

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Vol. 18, nr 3(57)

43--54

EN

Additive Manufacturing processes are being used increasingly in the scope of medicine and dentistry. As indicated by literature data, the durability and quality of medical implants is decisively influenced by surface modification. Insufficient quality of surface finishing leads, among others, to reduced service life of applied implants and to increased number of necessary revision surgeries. Furthermore, various types of finishing processes e.g. cleaning, shot peening or abrasive techniques are suggested by the manufacturers of products made by means of DMLS processes. Due to this fact, the analysis of proper formation of the surface layer of titanium products made by means of the method consisting in the direct laser sintering of metal powders (DMLS) was the subject matter of our research. Therefore, Ti-6Al-4V titanium alloy has been used for tests. The samples have been produced by means of EOSINT M280 system dedicated for laser sintering of metal powders. The surfaces of prepared samples have been subjected to shot peening process at three different values of working pressure (0.2, 0.3 and 0.4 MPa) by means of three different working media i.e. CrNi steel shot, crushed nut shells and ceramic balls. The characteristics of the materials used for shot peening process have been determined by means of Zeiss Ultra Plus scanning electron microscope. The samples have been subjected to profilometric measurements on Bruker Contour GT optical profilometer and the corrosion behaviour of Ti-6Al-4V titanium alloy in Ringer solution has been determined in electrode impedance spectroscopy (EIS) measurements by means of Atlas 0531 set dedicated for corrosion testing. The overall results of all tests indicate to favourable influence of the shot peening process on the corrosion behaviour of titanium alloy.

4

Effect of Alloying Elements on Plastic Workability and Corrosion Behavior of Ti-X (X = 6 Co, 8 Cr, 4 Fe, 6 Mn, 10 Mo, and 36 Nb) Binary Alloys

Zhao Z., Lee K.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1185--1190

EN

The purpose of this study was to investigate the effect of the alloying elements on the plastic workability and corrosion behavior of Ti-X (wt.%) (X = 6 Co, 8 Cr, 4 Fe, 6 Mn, 10 Mo, and 36 Nb) binary alloys. The alloys with a molybdenum equivalence of 10 wt.% were fabricated by a vacuum arc re-melting process and were then homogenized at a temperature 20°C greater than the beta transus temperature for 14.4 ks. The plastic workability was investigated under uniaxial cold rolling, while the corrosion behavior was examined in Ringer’s solution at 37°C. Among the Ti-X alloys, the Ti-8 wt.% Cr and Ti-6 wt.% Mn alloys showed an outstanding plastic workability and corrosion resistance, respectively.

5

Corrosion behaviour of aluminium matrix composites reinforced with sintered halloysite nanotubes

Dobrzański L. A., Reimann Ł., Kujawa M., Tomiczek B.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 73, nr 2

92--99

EN

Purpose: The aim of this study was to determine the effect of mass fraction and sintering temperature of the halloysite nanotubes on the corrosion behavior of the infiltrated AlSi12 matrix composites, concerning the matrix alloy. Design/methodology/approach: The corrosion resistance research was done with a potentiodynamic method. Electrochemical corrosion research was made in water centre of 3% NaCl at room temperature. Electrochemical studies of corrosion resistance were performed by determine the open circuit potential and saving the anodic polarization curves by applying to potential changes in the direction of anode and cathode at 1 mV/s. Based on the registered anodic polarization curves were determined: corrosion potential, passive layer breakdown potential, corrosion current density, polarization resistance. The value of corrosion current was determined using the Tafel extrapolation. Findings: Mass fraction of the halloysite nanotubes does not affect the corrosion resistance of the composites as opposed to their sintering temperature. The increase in temperature of a 200°C resulted in a significant reduction in corrosion resistance, but it is still higher than the corrosion of the matrix material. Practical implications: The aluminium alloy matrix composites reinforced with sintered preforms made by sintering halloysite nanotubes are modern materials that could find application in the automotive industry. The mechanical properties are greater than the alloy matrix while retaining a low density. It was necessary to examine the corrosion resistance as one of the important properties of the composites which are exposed to corrosive environments. Originality/value: Beyond the articles of the authors, analysis of mechanical properties and corrosion resistance of the infiltrated AlSi12 matrix composites reinforced by preform made by sintered halloysite were not found in the available literature.

6

Dimensional Changes, Microstructure, Microhardness Distributions And Corrosion Properties Of Iron And Iron-Manganese Sintered Materials

Kupková M., Hrubovčáková M., Zeleňák A., Sułowski M., Ciaś A., Oriňáková R., Morovská Turoňová P., Žáková K., Kupka M.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

639--642

EN

Iron samples and Fe-Mn alloys with Mn content of 25 wt.% and 30 wt.% were prepared by blending, compressing and sintering with the aim to study their dimensional changes, microstructure, microhardness distribution and primarily the electrochemical corrosion behaviour in a simulated body environment. The light microscopy (LM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-hardness measurements revealed a microheterogeneous multiphase structure of sintered Fe-Mn samples. The potentiodynamic tests have demonstrated that the corrosion rates of such Fe-Mn alloys immersed in Hank’s solution were higher than those for a pure iron, and also higher than the rates reported for homogeneous Fe-Mn alloys.

PL

Próbki żelazne oraz stopy Fe-Mn, zawierające 25 i 30% mas. Mn, przeznaczone na biomateriały, zostały przygotowane na drodze mielenia, prasowania oraz spiekania w celu zbadania ich zmian wymiarowych, mikrostruktury, rozkładu mikrotwardości oraz odporności korozyjnej w skumulowanych w warunkach laboratoryjnych, panujących w ciele człowieka. Badania z wykorzystaniem mikroskopii optycznej i skaningowej, wraz z EDX oraz pomiary mikrotwardości ujawniły mikroniejednorodność wielofazowej struktury spiekanych stopów Fe-Mn. Testy potentiometryczne wykazały, że współczynniki korozji spieków Fe-Mn były wyższe niż spieków wykonanych z czystego żelaza oraz z jednorodnych stopów Fe-Mn.

7

Studies of corrosion behaviour in acid environment of binary Mg-Li alloys for plastic forming

Białobrzeski A., Saja K., Żmudzińska M.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 3 spec.

25--28

EN

The article discusses studies and corrosion tests of binary Mg-Li alloys for plastic forming examined in an acid medium (5% HCl solution) for the time of 0-144 hours. In short it can be stated that corrosion of the examined Mg-Li alloys in 5% HCl solution proceeded in a similar mode in all the studied alloys, regardless of the lithium content.

8

Własności korozyjne cienkowarstwowych powłok TiN, CrN, TiCN, otrzymanych metodą łukowo-próżniową

Rogowska R.

Problemy Eksploatacji

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2006

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nr 3

181-188

PL

W artykule zaprezentowano odporność korozyjną powłok TiN, CrN, TiCN. Powłoki osadzono metodą łukowo-próżniową na stali SW7M i na węglu szklistym. Badania korozyjne powłok przeprowadzono w 0,8M roztworze NaCl. Wyznaczono potencjał obwodu otwartego, krzywe Tafela i Sterna, szybkość korozji, krzywą polaryzacji potencjodynamicznej i opór polaryzacji. Porównano właściwości korozyjne próbek pokrytych i niepokrytych powłokami. Uzyskane wyniki pokazują, że próbki ze stali SW7M pokryte powłokami posiadają potencjał korozyjny bardziej szlachetny.

EN

The article presents problems of corrosion resistance of TiN, CrN, TiCN coatings. The coatings were deposited on samples of SW7M steel and of the glass-carbon by means of the arc-vacuum method. The corrosion behaviour of TiN, CrN and TiCN coatings was examined in 0.8M NaCl solution. The study was performed using open circuit potential, Tafel and Stern curves, corrosion rate, potentiodynamic polarization curve and polarization resistance. The corrosion behaviour of coated and uncoated samples was compared. The results illustrate that coated specimens TiN, CrN, TiCN possess nobler potentials than the uncoated SW7M steel.

9

Azotowanie plazmowe i jego wpływ na odporność korozyjną stali nierdzewnych

Flis J.

Ochrona przed Korozją

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2005

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nr 4

86-89

PL

Azotowanie jest szeroko stosowane w celu zwiększenia wytrzymałości zmęczeniowej, twardości i odporności na zużycie. Azotowanie stali chromowych w temperaturach ok. 550-580oC powoduje wydzielanie azotków chromu, co prowadzi do znacznego polepszenia własności tribologicznych, ale także do pogorszenia odporności korozyjnej; azotowanie w niższych temperaturach ok. 380-450oC może polepszyć odporność korozyjną dzięki powstawaniu przesyconego stałego roztworu azotu bez wydzieleń obcych faz. Niniejszy artykuł opisuje korozyjne zachowanie plazmowo azotowanych stali nierdzewnych i metody zwiększenia ich odporności na korozję. Znaczną poprawę odporności po wysokotemperaturowym azotowaniu (550-580oC) uzyskano po pasywacji w roztworze NaOH/KNO3 lub w soli stopionej NaNO3/KNO3, a zwłaszcza po fosforanowaniu. Azotowanie nisko-temperaturowe powodowało silny wzrost odporności na korozję wżerową w roztworach chlorkowych. Analiza AES/XPS powierzchniowych produktów korozji wykazała powstawanie na stalach po nisko-temperaturowym azotowaniu większych ilości związków Cr(III), Mo(IV) i Mo(VI) mających działanie inhibicyjne; nagromadzanie tych związków może być powodem dużej odporności na korozje wżerową.

EN

Nitriding is widely used for increasing the fatigue strength, hardness and wear resistance of steels. Nitriding of chromium-bearing steels at temperatures of about 550-580oC results in the formation of chromium nitride precipitates which lead to a strong improvement of tribological properties, but also to a deterioration of corrosion resistance; nitriding at lower temperatures of about 380-450oC can enhance the corrosion resistance owing to the formation of a supersaturated solid solution of nitrogen without precipitates. This article describes the corrosion behaviour of plasma nitrided stainless steels and methods for increasing their corrosion resistance. A significant improvement of corrosion resistance after high-temperature nitriding (550-600oC) was achieved by passivation in a NaOH/KNO3 solution or in a molten NaNO3/KNO3 mixture, and particularly by phosphating. Low-temperature nitriding resulted in a strong increase of resistance to pitting corrosion in chloride solutions. An AES/XPS analysis of surface corrosion products showed that on low-temperature nitrided steels, the amount of inhibitive species Cr(III), Mo(IV) and Mo(VI) was larger; an increased amount of these species can be responsible for a high resistance to pitting corrosion.

10

Zachowanie korozyjne kompozytu A359-cząsteczki SiC

Bieniaś J., Surowska B.

Kompozyty

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2003

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R. 3, nr 8

380-384

PL

Artykuł przedstawia wyniki badań podatności na korozję materiału kompozytowego o osnowie aluminium stopu aluminium 359 (Aluminium Association), zawierającego 20% obj. cząsteczek SiC (359/20%SiC). Kompozyt 359/20%SiC został wytworzony w Instytucie Odlewnictwa w Krakowie. Znajduje on zastosowanie jako nowoczesny materiał konstrukcyjny w przemyśle samochodowym, szczególnie na tłoki i tarcze hamulcowe. Wprowadzenie cząstek wzmacniających znacząco może zmieniać zachowanie korozyjne tych materiałów. Publikowana literatura w zakresie kompozytów o osnowie stopów aluminium jest ograniczona i często sprzeczna. Jest to spowodowane faktem rozmaitości osnowy kompozytów i faz zbrojących, które mogą powodować zupełnie inne zachowanie korozyjne. Ponadto różne parametry wytwarzania wpływają na mikrostrukturę materiałów kompozytowych, a w konsekwencji na ich zachowanie korozyjne. Badania odporności na korozję kompozytu 359/20%SiC wykonano za pomocą przyśpieszonych badań elektrochemicznych metodą potencjodynamiczną. Analizę korozyjną tego materiału odniesiono do charakterystyki korozyjnej stopu aluminium AK9 (AlSi9Mg). Pomiary potencjodynamiczne wykonano w 3,5% wag. roztworze NaCl (pH = 7,0) w temperaturze 25°C. Badania mikrostrukturalne przeprowadzono za pomocą mikroskopu optycznego ZEISS i skaningowego mikroskopu elektronowego (SEM) Hitachi S-3500N. W strukturze kompozytu na tle roztworu stałego i drobnoziarnistej eutektyki widoczne są cząsteczki węglika krzemu. Rozkład cząsteczek SiC w strukturze był dość równomierny (rys. la). Przebieg krzywych polaryzacji anodowej w 3,5% NaCl wskazuje, że są to krzywe metalu ulegającego samorzutnej pasywacji (rys. 2). Wyznaczone potencjały Ek, Eb, Er,[ delta]Eb, [delta]Er, z badań elektrochemicznych i analizy krzywych polaryzacji anodowej dla kompozytu i stopu AK9 są bardzo podobne (tab. 2). W strukturze stopu AK9 (rys. 3) występują liczne wżery, których głębokość zawiera się w granicach 8--16 }mikro]m. Wżery lokują się w eutektyce [alfa]+Si. W przypadku materiału kompozytowego 359/20%SiC obserwuje się jeszcze bardziej liczne i głębsze wżery (10--24 [mikro]m), które także lokują się w eutektyce [alfa]+Si pomiędzy cząsteczkami SiC (rys. rys. 4 i 5). Przeprowadzone badania nie wykazały znaczącego wpływu cząsteczek SiC na wzrost podatności na korozję wżerową w porównaniu do stopu AK9, co potwierdzają również dane literaturowe.

EN

The paper presents results of the studies on the susceptibility of Aluminium Matrix Composite to corrosion. The subject of the examinations was a composite with the 359 aluminium alloy matrix (Aluminium Association) containing 20 vol.% of SiC particles (359/20%SiC). The 359/20%SiC composite has been synthesized at the Foundry Research Institute in Cracow. This material can be applied as a modern construction material in automotive industry, particularly for brake discs and pistons. However, the addition of the reinforcement particles could significantly influence the corrosion behaviour of these materials. Generally published literature on the corrosion of aluminium-based composites is rather limited and often contradictory. This is due to the fact that there is a variety of aluminium alloy matrix and reinforcement type combinations which may exhibit a completely different corrosion behaviour. In addition, processing parameters can heavily affect composite microstructure and, consequently, their corrosion behaviour. The studies on the 359/20%SiC composite corrosion resistance were carried out by accelerated electrochemical studies using the potentiodynamic method. The corrosion analysis of this material was then related to the corrosion characteristics of AK9 (AlSi9Mg) aluminium alloy. The potentiodynamic measurements were taken in the 3.5 wt.% NaCl water solution (pH = = 7.0) at the temperature of 25°C. Microstructure analysis of the specimens was examined using ZEISS model optical microscope and Hitachi S-3500N scanning electron microscopy (SEM). Silicon carbide particles were seen in the matrix on base of the [alpha]-Al solid solution, a fine-grained eutectic [alpha]+Si (Fig. 1a). Distribution of SiC in the structure was quite uniform. The course of the anodic polarization curves in the 3.5 wt.% NaCl solutions suggests characteristic curves for the metal that undergoes spontaneous passivation (Fig. 2) Potentials of the Ek, Eb, Er, [delta]Eb, [delta]Er determined in electrochemical studies and analyses of the anodic polarisation curves, for both, composite and AK9 alloy, are very similar (Tab. 1). In the microstructure of AK9 alloy (Fig. 3) there arę numerous pits whose depth ranges from 8--16 [micro]m. The pits are located in [alpha]+Si eutectic. In the case of the composite material more numerous and deeper pits (10--24 [micro]m) were observed which also locate in the [alpha]+Si eutectic between SiC particles (Figs. 4, 5). The conducted examinations did not show significant influence of SiC particles on the increase of susceptibility to pitting corrosion in comparison to AK9 alloy, what is confirmed by the literature data.