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1

Silesian Ridge in the light of petrological analyses and LA-ICP MS U-Pb analyses of the cohesive debrites from the Istebna Formation (Silesian Nappe, Outer Western Carpathians, Poland)

Szczuka Monika, Gawęda Aleksandra, Waśkowska Anna, Golonka Jan, Szopa Krzysztof, Chew David, Drakou Foteini

Geological Quarterly

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2022

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Vol. 66, No. 2

art. no. 20

EN

Exotic clasts present in flysch deposits of the Western Outer Carpathians enable investigation and reconstruction of the eroded crystalline basement of the Silesian Ridge. The flysch rocks of the Istebna Formation (Jasnowice Member: Paleocene) in the Silesian Nappe contain magmatic and metamorphic clasts derived from the Silesian Ridge basement. The crystalline rock fragments acquired from cohesive debrites were analyzed petrographically and geochemically, and zircon and rutile crystals were subject to LA-ICP-MS U-Pb dating. Granitoid clasts yielded Meso-Variscan U-Pb zircon ages (325.7 and 330.6 Ma), with older (Neoproterozoic to Paleoproterozoic) inherited cores and eNd330 = –12.0 (TDM age of 1.98 Ga). The orthogneiss clast yielded a protolith age of 1635 Ma and fingerprint of thermal reworking at ~288 Ma. Zircon crystals from the detrital clasts yielded similar U-Pb zircon ages to the granitoid clasts (311.5 to 391 and 331 Ma). The rutile crystals from sandstone yielded concordia age of 344.7 Ma. Zircon crystals from paragneiss, interpreted as a granitoid envelope, yielded 238U/206Pb ages between 557 and 686 Ma and include an inherited core of age ~1207.4 ±33.8 Ma. Age data from exotic clasts and the detrital zircon and rutile fraction suggest the core part of the Silesian Ridge was a Neoproterozoic to Mesoproterozoic envelope intruded by Meso-Variscan granitoid plutons.

2

Insights into the interaction between octyl hydroxamic acid and the rutile surface activated by lead ion

Cao Qinbo, Chen Xiumin, Zou Heng, Yu Xingcai

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 5

928--938

EN

The flotation of rutile can be enhanced using lead ion as an activator. However, the binding behavior of collector on the activated rutile surface is still not fully understood. In this work, flotation and theoretical calculation approaches were employed to evaluate the activation behavior of lead ion in the flotation of rutile with octyl hydroxamic acid (OHA). Flotation results indicated that the activation flotation with lead ion should be conducted at pH 6.5. The binding features of OHA molecule on the inactivated and Pb-activated rutile surfaces were both investigated by density functional theory (DFT) studies. The OHA molecule may dissociate into OHA− anion on the inactivated rutile surface, generating a new Ti–O bond. Differently, the chelate complex of Pb-OHA anion was generated on the activated rutile surface, producing two Pb–O bonds. The adsorption of OHA onto the activated rutile surface was more stable than that on the inactivated rutile surface, due to the formation of more chemical bonds on the activated rutile surface. The DFT calculation results delineated the role of Pb2+ in the rutile flotation with OHA.

3

Flotation separation of rutile from almandine using octadecyl amine polyoxyethylene ether as collector

Li Hongqiang, Zheng Huifang, Chen Qian, Kasomo Richard M., Leng Jiahao, Weng Xiaoqing, Song Shaoxian, Xiao Linbo, Tian Chengtao

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 4

653--664

EN

In this study, the flotation separation of rutile from almandine using cationic surfactant Octadecyl amine polyoxyethylene ether (AC1815) as a new collector was investigated. The adsorption mechanism of AC1815 on rutile was illustrated through zeta potential measurement, infrared spectrum and XPS analyses. The flotation experiments demonstrated that AC1815 exhibited an excellent collecting ability and selectivity for rutile. The results of zeta potential measurements and XPS analysis indicated that more AC1815 was adsorbed on rutile surface instead of almandine. The adsorption mechanism of AC1815on rutile was mainly attributed to the electrostatic interaction between the positively charged molecules of AC1815 and the negatively charged rutile surface, and the hydrogen bonding between the protonated ≡NH+, ≡N group of AC1815 and Ti-OH on rutile surface.

4

Electrokinetic and flotation behavior of rutile in the presence of lead ions and aluminium ions

Cheng Hongwei, Liu Changmiao, Guo Zhenxu, Feng Ansheng, Wei Min, Lv Zihu, Wu Dongyin, Zhao Dengkui

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 2

458--466

EN

The effects of Pb(II) ions and Al(III) ions on the electro kinetic and flotation behavior of rutile were investigated by micro-flotation tests, zeta potential measurements and solution chemistry analysis. Micro-flotation results indicate that the Pb(II) ions can effectively improve the flotation recovery of rutile while the Al(III) ions significantly inhibit the flotation of rutile. Zeta potential measurements reveal that a collector styrene phosphoric acid (SPA) can adsorb on the rutile surface after the addition of Pb(II) ions, but hardly adsorb on the rutile surface after the addition of Al(III) ions. Pb(II) ions adsorb on the rutile surface in the form of Pb(OH)+ and Pb(OH)2(s), and the latter one is the main reason that activates rutile flotation. Al(III) ions adsorb on the rutile surface mainly in the form of Al(OH)3(s), which prevent the direct interaction between the rutile and the collector, resulting in a decrease of rutile flotation recovery.

5

Adsorption of lead ion on the hydrated rutile (110) surface: a DFT calculation study

Zou Heng, Cao Qinbo, Chen Xiumin, Liu Dianwen

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 4

951--959

EN

The adsorption behavior of lead species on the hydrated rutile surface was investigated with inductively coupled plasma mass spectrometry (ICP-MS) measurements and density functional theory (DFT) calculations. ICP-MS experiments suggested that lead species can be readily absorbed by the rutile powder in water at pH 6.5. From the ICP-MS results and the species distribution of Pb2+, it was concluded that Pb2+ was the major lead species adsorbing at the rutile/water interface at the pH of 6.5. DFT calculation results indicated that Pb2+ could adsorb at four different sites on the surface. At each site, water molecules or OH groups were involved in the reaction with Pb2+. The water molecules/OH groups on the rutile surface play an important role during the adsorption of Pb2+ on the hydrated rutile surface.

6

Effects of Cr and Fe co-doping on structural, optical, electrical and magnetic properties of titanium dioxide (TiO2)

Waseem S., Anjum S., Mustafa L., Dar A., Bashir F., Zia R.

Materials Science Poland

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2015

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Vol. 33, No. 3

508--514

EN

A series of Ti0.9Fe0.1-xCrxO2 (where x = 0.0, 0.02, 0.04, 0.6, 0.08, 0.10) was synthesized using the powder metallurgy route. The structural, morphological, magnetic, optical and electrical properties were investigated by X-ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), UV-Vis spectroscopy and four probe technique, respectively. The rutile phase was confirmed by XRD analysis which was also verified by Raman spectroscopy. It was observed that the grain size increased as the concentration of Cr increased. M-H loops extracted from VSM analysis revealed anti-ferromagnetic, weak ferromagnetic and paramagnetic behaviors at room temperature. The band gap energy and resistivity measurements exhibited the semiconducting nature of Ti0.9Fe0.1-xCrxO2 based diluted magnetic semiconductors.

7

Crystal Structure And Optical Properties Of TiO2 Thin Films Prepared By Reactive RF Magnetron Sputtering

Goto S., Adachi Y., Matsuda K., Nose M.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

965--967

EN

In sputtering deposition process of TiO2, metal Ti or sintered TiO2 target is used as deposition source. In this study, we have compared the characteristic of target materials. When TiO2 target was used, stoichiometric TiO2 films was deposited under the Ar atmosphere containing 1.0% of oxygen. The highest sputtering rate under this atmosphere was 3.9nm/min at 3.4W/cm2. But, sintered TiO2 target is fragile and cannot endure higher density of input power than 3.4W/cm2. On the other hand, Ti target needs higher oxygen concentration (8%) in sputtering gas atmosphere for obtaining rutile/anatase. Even though Ti target can be input twice power density of 7.9W/cm2, the highest deposition rate for Ti target was 1.4/nm, which was ~35% of the highest rate for TiO2 target. Then we have study out the composite target consisting of Ti plate and TiO2 chips. Using the composite target, stoichiometric TiO2 films were prepared in the rate of 9.6nm/min at 6.8 W/cm2 under the atmosphere of Ar/2.5%O2. Furthermore, we have found that the TiO2 films obtained from the composite target consisted of about 100% anatase, whereas TiO2 films obtained from other target have rutile dominant structure. The optical band gap energy of the film is determined by using the Tauc plot. The calculated band gap energies for the films deposited by Ti target and composite target were 2.95 and 3.24eV, which are equivalent to that of rutile and anatase structure, respectively.

PL

W procesie nanoszenia TiO2 metodą rozpylania, jako tarczy używano metalicznego Ti lub spiekanego TiO2. W pracy dokonano porównania obu materiałów. W przypadku zastosowania jako tarczy TiO2 przy nanoszeniu w atmosferze Ar zawierającym 1,0% tlenu otrzymano stechiometryczną warstwę TiO2. Największa uzyskana szybkość rozpylania w tej atmosferze wyniosła 3,9 nm/min przy gęstości mocy wejściowej 3,4 W/cm2. Jednak spiekany TiO2 jest kruchy i nie wytrzymuje gęstości mocy wejściowej powyżej 3,4 W/cm2. Z drugiej strony, przy rozpylaniu z tarczy Ti konieczne jest zwiększone stężenie tlenu (8%) w atmosferze aby otrzymać fazę rutyl/anataz. Mimo że tarcza Ti wytrzymuje gęstość mocy dwa razy wyższą niż TiO2 (7,9 W/cm2), największa uzyskana szybkość rozpylania wynosiła 1,4 nm/min, co stanowi ~35% najwyższej szybkości uzyskanej dla tarczy TiO2. Zbadano także tarczę kompozytową składające się z płyty Ti oraz wiórów TiO2. W przypadku zastosowania tarczy kompozytowej, szybkość rozpylania wyniosła 9,6 nm/min przy mocy 6,8 W/cm2 w atmosferze Ar/2,5%O2. Dodatkowo, warstwy TiO2 otrzymane z tarczy kompozytowej zawierały około 100% anatazu, podczas gdy w przypadku warstw otrzymanych z pozostałych tarcz dominowała faza rutylu. Szerokość przerwy energetycznej wyznaczono na podstawie wykresu Tauca. Obliczone wartości przerwy energetycznej wynosiły 2,95 eV dla podłoża Ti i 3,24 eV dla podłoża kompozytowego, co odpowiada wartością przerw odpowiednio dla rutylu i anatazu.

8

Study of the anatase to rutile transformation kinetics of the modified TiO2

Grzmil B., Gleń M., Kic B., Lubkowski K.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 2

73–80

EN

TiO2 attracts much interest because of its many potential applications. The use of titanium dioxide strongly depends on its polymorphic form: brookite, anatase, or rutile. Only rutile and anatase play an important role in industry. Anatase as a metastable form undergoes a non-reversible transformation into rutile. Understanding the kinetics of phase transformation and the processes of crystal growth of a material is essential for controlling its structure and, thus, its specific properties. The main purpose of this paper is to explain the anatase to rutile recrystallization kinetics in the modified TiO2 calcined from industrial hydrated titanium dioxide. The apparent activation energy of anatase to rutile transformation and the average size of titanium dioxide crystallites were determined for the unmodified TiO2 and TiO2 modified with P, K, Al, B, Zn, Zr, Ce, Sn, or Sb introduced in the amount of 0.5 mol% and 1.0 mol% when recalculated for their oxides. The growth of TiO2 crystallites during calcination was strongly inhibited by P, Ce and Zr, and inhibited to a lesser degree by Al, Sn and Sb. B and Zn did not affect the investigated process and K accelerated crystallites growth. The values of apparent activation energy depending on a modifier formed a relationship: Al

9

Zastosowanie metody dwuetapowego utleniania do badań mechanizmu narastania zgorzeliny rutylowej na tytanie

Gil A., Kuc A.

Materiały Ceramiczne

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2012

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T. 64, nr 2

188-191

PL

Badania mechanizmu narastania zgorzeliny TiO2 na tytanie z zastosowaniem metody obojętnych markerów prowadzone były w latach 60-tych ubiegłego wieku przez Kofstada. Dla temperatury 900 stopni C platynowy marker zlokalizowany został na powierzchni warstwy rutylowej. Powyższy rezultat, w połączeniu z wynikami badań przewodnictwa elektrycznego TiO2, pozwoliły Kofstadowi na zaproponowanie modelu struktury defektowej tego tlenku, w którym, jako dominujące defekty punkowe, przyjęte zostały wakancje anionowe. Powyższy model był przez długie lata uważany jako poprawny, ale z czasem zaczął budzić pewne wątpliwości. Zauważyć należy, że położenie markera na powierzchni warstwy tlenkowej nie daje jednoznacznej informacji dotyczącej dominującego mechanizmu transportu reagentów w zgorzelinie. Marker na powierzchni zgorzeliny stwierdza się zarówno w przypadku dordzeniowego transportu utleniacza po defektach punktowych, jak i po defektach dwu- i trójwymiarowych (granice ziaren, mikroszczeliny, otwarte pory). Aby to rozstrzygnąć przeprowadzić należało badania dwuetapowego utleniania z zastosowaniem izotopów tlenu 16O2 i 18O2. W pracy zaprezentowane zostały wyniki dwuetapowego utleniania tytanu dla temperatury 900°C. Do wyznaczenia głębokościowych rozkładów stężeń obu izotopów tlenu w zgorzelinie zastosowano technikę analizy powierzchniowej SNMS. Uzyskany wynik jednoznacznie wykluczył dyfuzję tlenu po defektach punktowych w TiO2 jako dominujący mechanizm transportu reagentów w warstwowej zgorzelinie rutylowej na tytanie.

EN

The growth mechanism of rutile scale on titanium using the marker method was investigated in 60th years of the preceding century by Kofstad. For a temperature of 900 °C, a Pt-marker was found on the surface of the rutile layer. Above-mentioned result, as well as the studies of electric conductivity of TiO2, have allowed Kofstad to propose a model of the defect structure of this oxide, in which oxygen vacancies were suggested as the predominant point defects. This model has been accepted to be a correct one for a long time but has seemed doubtful recently. It is worth to note, that the marker localization on the surface of the scale does not give one-valued answer concerning the predominant mechanism of reagents transport in the oxide layer. The marker is localized on the scale surface both in case of the predominant transport of the oxygen via point defects and via two- and three-dimensional defects in the oxide (grain boundaries, micro-cracks, open pores). In order to settle the matter, it belongs to carry of a two-stage oxidation experiment using the 16O2 and 18O2 oxygen isotopes. In this paper, the results of the two-stage oxidation of titanium at 900 °C are presented. The depth-concentration profiles of the oxygen isotopes in the rutile scale were determined using the SNMS surface-analytical technique. The obtained results exclude oxygen diffusion via point defects in TiO2-x as the predominant mechanism of reagents transport in the layered rutile scale on titanium.

10

Determination of the electronic band structure of the rutile polymorph of TiO2: a quantum chemical approach

Bardziński P. J.

Materials Science Poland

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2011

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Vol. 29, No. 3

223--232

EN

The aim of this work is the investigation of the relationship between the electronic band structure of the TiO2 rutile and the dimensionality of the system. For three dimensional system the bulk form of rutile was considered, while a slab model was chosen in order to represent the titanium (IV) dioxide (110) surface. The influence of changing the number of atomic layers on the bandgap value for the (110) surface was also examined. Density of states referring to the bands from the first valence band up to the bottom of the conduction band was projected on the whole set of atomic orbitals as well as on the significant shells of the titanium and oxygen atoms. Ab initio calculations with a B3LYP functional were carried out. Basis sets used were modified Ti 86-411(d31)G darco unpub and O 8-411 muscat 1999. The results are compared with experimental and computational data already available in the literature. Surface termination problem was discussed and the application of the obtained results as a starting point to obtain the first model of the rutile titania nanotube was proposed. The surface formation energies for rutile planes with a different surface terminations were compared and the modification to the equation needed for surface energy calculation was introduced.

11

Effect of calcination temperature on photocatalytic activity of TiO2. Photodecomposition of mono- and polyazo dyes in water

Mozia S.

Polish Journal of Chemical Technology

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2008

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Vol. 10, nr 3

42-49

EN

The presented studies have focused on the influence of TiO2 properties, such as crystalline phase, crystallite size and surface area, on the effectiveness of degradation of azo dyes in water under UV irradiation. Two monoazo dyes: Acid Red 18 (AR18, C20H11N2Na3O10S3) and Acid Yellow 36 (AY36, C18H14N3NaO3S), and one polyazo dye Direct Green 99 (DG99, C44H28N12Na4O14S4) were applied as model compounds. The photocatalysts were prepared from a crude titanium dioxide obtained directly from the production line (sulfate technology) at the Chemical Factory "Police" (Poland). The crude TiO2 was calcinated in air for 1-4h at the temperatures ranging from 600 to 800°C. The BET specific surface area of TiO2 decreased gradually with increasing the calcination temperature. The crude TiO2 exhibited specific surface area of 277 m2/g. In case of the catalysts heated at 600, 700 and 800°C the BET surface area amounted to 62.3-53.3, 33.4-26.8 and 8.9-8.3 m2/g, for the calcination time of 1-4h, respectively. The crystallite size of anatase increased with increasing heat treatment temperature and ranged from 19 to 53 nm, for the temperatures of 600-800°C, respectively. The catalysts annealed at 600 and 700°C contained primarily anatase phase (94-97%), whereas the photocatalysts heated at 800°C were composed mainly of rutile (97-99%). The highest effectiveness of azo dyes degradation was obtained in case of the photocatalyst calcinated for 1h at 700°C. The photocatalyst was composed mainly of anatase (97%) with crystallite size of 27 nm. The most effectively photodegraded was AR18, having the molecular weight of 640.4 g/mol. The most difficult to degrade was AY36 exhibiting the lowest molecular weight from all the dyes used (375.4 g/mol).

12

Micro-floatability of rutile and zircon with soap and amine type collectors

Hosten C.

Physicochemical Problems of Mineral Processing

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2001

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Vol. 35

161-170

EN

Single-mineral floatability of pure, heavy sand rutile and zircon minerals using sodium oleate and hydrogenated tallow amine acetate as collectors was studied by a micro-flotation device over a wide pH range from 2 to 12, at three levels of the collectors and two levels of a polypropylene glycol type frother. Rutile yielded a peak foatability at pH 6 with sodium oleate, and floated reasonably well over a wide pH range from 2 to 8 with the amine collector. An abrupt deterioration of the floatability of rutile was observed at pH>8. The maximal floatability range for zircon was from pH 6 to 10, followed by a sharp decrease at pH>10, with both of the collectors. The floatability of zircon decreased sharply with decreasing pH in the acidic medium, below pH 6. The results were discussed in view of collector species distribution as a function of pH to suggest adsorption mechanisms for the collectors. The upper critical flotation pH values for the minerals seemed to be sufficiently distinct to suggest a potential for the differential flotation of the minerals in the alkaline medium with both of the collectors tested.

PL

Flotowalność czystych minerałów rutylu i cyrkonu badano przy pomocy testów mikroflotacyjnych. Kolektorami w procesie flotacji były oleinian sadu i octan talowej aminy. Badania flotacyjne prowadzono w zakresie pH od 2 do 12, stosując trzy różne stężenia kolektora i dwa stężenia odczynnika pianotwórczego (glikol polipropylenowy). Rutyl wykazywał maksimum flotowalności przy pH 6, przy użyciu jako kolektora oleinianu sodu. Stosując kolektor aminowy dobre wyniki flotacji rutylu uzyskano w zakresie pH od 2 do 8. Wyraźny spadek flotowalności obserwowano przy pH>8. Maksymalna flotowalność cyrkonu, przy użyciu obu kolektorów, była w zakresie pH 6-10. Flotowalność cyrkonu malała szybko przy pH>10. Równie, wyraźny spadek flotowalności cyrkonu obserwowano w środowisku kwaśnym pH poniżej 6. Otrzymane wyniki z flotacji zostaly przedyskutowane w oparciu o prawdopodobne mechanizmy adsorpcji badanych kolektorów do powierzchni minerałów. Różnice w flotacji minerałów w obszarze alkalicznym sugeruja możliwość separcji tych minerałów przy zastosowaniu badanych kolektorów flotacyjnych.

13

Struktura i właściwości powłok jednowarstwowych TiO2 i ZrN oraz dwuwarstwowych TiO2-ZrN na stali 2H13.

Głuszek J., Masalski J., Prajzner A., Markowski J., Dudziński W.

Inżynieria Materiałowa

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1999

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R. XX, nr 5

325-327

PL

W pracy przedstawiono technologię nanoszenia warstw TiO2, ZrN i TiO2-ZrN na stali ferrytycznej 2H13 za pomocą aktywowanego, reaktywnego naparowania z polaryzacją podłoża (BARE). Warstwa TiO2 składa sie z rutylu krystalizującego w układzie regularnym, natomiast warstwa ZrN z azotku cyrkonu krystalizującego w układzie heksagonalnym typu węglika wolframu. Średnie wielkości krystalitów wynosiły 350 angstremów dla TiO2 i 95 angstremów dla ZrN. Za pomocą metod stało- i zmiennoprądowych ustalono, że badane powłoki hamują procesy katodowe i zmniejszają szybkość korozji ogólnej. Powłoki jednowarstwowe nie polepszają odporności na korozję wżerową, natomiast powłoka dwuwarstwowa TiO2-ZrN znacznie poprawia odporność na korozję.

EN

The preparation of coating layers of TiO2, ZrN and TiO2-ZrN obtained by bias activated reactive evaporation (BARE) method on 2H13 steel substrate was presented. TiO2 coating consists of rutile crystallizing in cubic system and ZrN coating consists of zirconium nitride crystallizing in hexagonal system type tungsten carbide. The mean size of crystalline grains were 350 angstrems for TiO2 and 95 angstrems for ZrN. The protective of the individual coatings were evaluated by d.c. and a.c. measurements. Cathodic processes are inhibited on all coatings and corrosion rates are decreased. The monolayer coatings do not improve pitting corrosion resistance but two-layer TiO2-ZrO2 composite coatings improve distincly pitting corrosion resistance.