Djordje Mandrino

• Institute of Metals and Technology

Two binary biodegradable Mg-alloys and one ternary biodegradable Mg-alloy (Mg-0.3Ca, Mg-5Zn and Mg-5Zn-0.3Ca, all in wt%) were investigated. Surface-sensitive X-ray photoelectron spectroscopy analyses (XPS) of the alloy surfaces before and after immersion in simulated body fluid (SBF) were performed. The XPS analysis of the samples before the immer...

Alloying with Mn can significantly influence the magnetic behavior of soft-magnetic silicon steel. Therefore, the formation of high-temperature oxides on an Fe-Si-Al alloy for electrical steel with the addition of 1 wt.% Mn is investigated in this study. X-ray diffraction spectra of a high-manganese Fe-Si-Al alloy were measured at a series of incre...

In this study, a surface-sensitive Auger Electron Spectroscopy (AES) was used to comprehensively characterize titanium-oxynitride coatings on metals for high efficient solar absorbers. Primary information obtained from the AES is chemical composition, but chemical state of the elements may also be estimated. Corroborative information about the coat...

Nitrocarburised coatings may be produced using different processing methods and/or process parameters, allowing a variety of possible mechanical properties, surface morphologies and chemical compositions, and thus, as a result, their friction and wear behaviour under tribological loading can be very different. In the present work, various examples...

Graphical abstract from "I. Velkavrh, F. Ausserer, S. Klien, J. Voyer, A. Diem, K. Lingenhöle, F. Kafexhiu, D. Mandrino, B. Podgornik, J. Rattenberger, H. Schröttner, F. Hofer, Properties of nitrocarburised and oxidised steel surfaces and the correlation with their tribological behaviour under unlubricated sliding conditions, Wear 410-411 (2018) 12...

In the present study, DIN 31CrMoV9 (1.8519) steel samples were initially treated by salt bath- (SNC), gas- (GNC) and plasma-nitrocarburising (PNC) and afterwards oxidised for increased corrosion protection. The thickness and hardness of the oxide and compound layer as well as the diffusion zone were measured. Surface topographies and microstructures...

The main goal of this research was to improve a carbonate-type foaming agent for the production of Al foams. Various systematic treatments, i.e. mechanical, thermal and chemical, were applied to naturally occurring dolomite, in order to affect its thermal decomposition. Structural modifications after the treatments as well as after the thermal deco...

Action of lubrication additives in the case of uncoated steel surfaces, including the type and mechanism of tribofilm formation is well known and understood. However, contact type of tribofilms which might form under the tribological contact between CrN coated surfaces, remains more or less unexplored. The aim of this investigation was to study the...

After 18 months in service, localized corrosion pits were observed on stainless-steel products used in the food- and beverage-processing environments of a snack bar. In this study we investigated whether the observed corrosion of the austenitic and ferritic stainless steels AISI 304 and AISI 430, respectively, could be caused by the improper mainte...

In the case of metallic surfaces, the action of extreme-pressure (EP) and anti-wear (AW) additives is well understood and has been described in detail. However, this is not the case for coated surfaces. The aim of the present investigation was to determine the influence of additive type and concentration on the tribological behaviour of boundary-lu...

Polyethylene glycol (PEG)- and polydimethylsiloxane (PDMS)-based corrosion protection coatings of the AISI 316L stainless steel surface were investigated. X-ray photoelectron spectroscopy (XPS) was used to confirm successful deposition of the coatings on the substrate as well as to estimate the thickness for both coating types. Contact angle measur...

Topmost layer of a submicrometre Zn-Al corrosion protection metallic coating containing also Mg and Ca as minor constituents was depth profiled using Auger electron spectroscopy. Oxidation state dependent kinetic energy shifts of the Mg KLL and Ca LMM peaks were used to evaluate the oxide state of the respective minor elements along the profile. An...

Two different, commercial, thin, metallic layers, one with a submicron thickness, containing Zn and Al as the main constituents, were depth profiled using Auger electron spectroscopy (AES). Large, oxidation-state-dependent, kinetic-energy shifts of the Al KLL and Zn LMM peaks were used to evaluate the oxide state of the elements inside the layers....

Zn–Al metallized film capacitors in two different production stages were investigated to explain the decrease of capacitors performance with time. Unsealed and sealed capacitors with different aluminium content in metallization layer were investigated. Scanning electron microscopy (SEM) was used to image the surface of the metallization layers, ene...

The decomposition of commercially available TiH2 was investigated while performing different thermal treatments. TiH2 powder, which is widely used as a foaming agent, was heat treated at 450 °C for various times, from 15 min to 120 min. Scanning electron microscopy (SEM) images of the surfaces at different magnifications were obtained and interpret...

Because of their unique mechanical properties, shape memory and super elasticity, durability and biocompatibility, Ni‐Ti alloys are the most important memory shape alloys for applications in a wide range of medical implants and devices. These alloys contain approximately equal Ni and Ti atomic concentrations, meaning medical applications are still...

Titanium hydride is well known for its stability in air because of formation of thin TiO2 oxide layer on top of TiH2 powder particles. Formation of the oxide layer is directly related to high affinity of Ti to oxygen and it can be formed in few seconds also on top of TiH2 particles in low vacuum. On the other hand, thickness of TiO2 layer on the fo...

The surface oxidation of duplex stainless steel (DSS 2205) was studied by X-ray photoelectron spectroscopy (XPS). The experiments were performed on the alloy after controlled oxidation in a chloride-enriched solution at controlled potentials. The evolution of the passive film formed on the DSS in a chloride solution was studied using cyclic voltamm...

Thin oxide films were produced by the exposure of polished, sputter-cleaned metallic surfaces kept in UHV to several thousands of Langmuirs at 10−5 mbar oxygen yielding oxide layers of several nanometers. Metallic substrates used were iron, chromium and duplex stainless steel (DSS 2205). AES and XPS profiling analyses were performed. An attempt was...

It was attempted to measure parameters of Fe 2p and S 2p transitions for Fe and S in FeS to compare them with range of values obtainable from the literature. FeS specimen was manufactured from the standard material used for chemical analysis. X-ray Photoelectron spectroscopy (XPS) was first performed on non-polished and then on polished surface. Sc...

An X-ray photoelectron spectroscopy analysis of the surface of fully processed, non-oriented, electrical steel sheet was performed in an attempt to elucidate the chemistry of the complex oxide scale. Ar+ sputtering was used to clean the surface contamination. Not only Fe2+, but also Fe0 states were detected in addition to the Fe3+ in the top severa...

Chemical surface modification can be used as a method for corrosion protection of sensitive powders based on intermetallic alloys between rare earth and transition metals. Surface coating is used for preventing fine powders, based on Nd-Fe-B, or Sm2Fe17−xTaxN3−δ prepared by HDDR processing and mechanically alloying, from hydrolysis. Powders coated...

The total replacement of joints by the implantation of permanently indwelling prosthetic components has been one of the major successes of modern surgery in terms of relieving pain and correcting deformity. However, the aseptic loosening of a prosthetic-joint component is the most common reason for joint-revision surgery. Furthermore, it is thought...

Thin oxide layers were produced by exposing polished and ion-sputtered duplex stainless steel surfaces to ambient conditions for 24 h. Another type of oxide layer was produced in a plasma passivation chamber. These layers were then studied using SEM and high-resolution Auger electron spectroscopy (AES) profiling. The exposure under ambient conditio...

Thin oxide layers were produced by exposure of polished and sputter-cleaned stainless steel samples to approximately 10−5 mbar oxygen administered into the fast entry chamber previously pumped down to 10−8 mbar. XPS as well as AES depth profiling determined principal constituents of the oxide layer as chromium and iron oxides and estimated layers t...

A microstructural characterization of the powder-metallurgy high-speed-steel S390 Microclean was performed based on an elemental distribution of the carbide phase as well as crystallographic analyses. The results showed that there were two types of carbides present: vanadium-rich carbides, which were not chemically homogeneous and exhibited a tungs...

Titanium hydride powder, manufactured by ball milling titanium in a hydrogen atmosphere down to micron-sized particles, was analyzed by X-ray Photoelectron Spectroscopy (XPS). A strong titanium oxide signal was also measured, which decreased somewhat after intense sputtering of the sample, but was impossible to get rid of completely. This was proba...

A car’s drive shaft, machined from case-hardened steel that was carbo-nitrided, quenched and tempered, ruptured at an early stage of its use. Both sides of the fractured shaft were delivered for an investigation in order to discover the cause of the rupture. The fractured area was partially damaged due to the mutual rubbing of the shaft’s sides. Th...

Three different techniques were used to produce thin oxide layers on polished and sputter-cleaned duplex stainless-steel samples. These samples were exposed to 10−5 mbar of pure oxygen inside the vacuum chamber, exposed to ambient conditions for 24 h, and plasma oxidized. The oxide layers thus produced were analysed using XPS depth profiling in ord...

Multilayer Ti(B-N) layers have been sandwiched between a TiN coating on treated AISI H11 steel and an outermost TiB2 coating. The films were deposited with plasma-assisted chemical vapour deposition (PACVD) and have been characterized using electron spectroscopy techniques. The thickness of the total coating is 1.6 μm and comprised 21 layers. Earli...

Nanowire-type materials produced by single-step synthesis were investigated by XPS and HR AES. A sufficient quantity of these materials was produced for the XPS analyses. AES analyses at selected spots or along selected lines on the surface of the bundles of the material were also performed. HR AES measurements on bundles of different thicknesses w...

Protective oxide and/or nitride layers on AISI 321 stainless steel were prepared by thermal treatment in air and two controlled atmospheres in a laboratory simulation of an actual technological procedure. Samples’ surface was imaged by Scanning Electron Microscopy (SEM), elemental composition of the substrates was checked by Wavelength Dispersive S...

Soft magnetic materials derived from rapidly solidified FeSiB alloys exhibit excellent soft magnetic properties due to the crystallisation of nanoscale α-iron grains in an amorphous matrix. It has been proposed that decreasing the critical solidification rate by choosing the multi-atomic alloying system with negative enthalpies of mixing among elem...

A protective oxide layer was formed on the surface of stainless steel by standard industrial-type thermal treatment. Additional post-thermal treatment annealing and polishing followed by annealing were applied in an attempt to improve characteristics of the layers. Oxide layers formed on samples without and with different types of post-thermal trea...

Protective oxide and/or nitride layers on AISI 321 stainless steel were prepared by thermal treatment in air and two controlled atmospheres in a laboratory simulation of an actual technological procedure. Samples’ surface was imaged by Scanning Electron Microscopy (SEM), elemental composition of the substrates was checked by Wavelength Dispersive S...

During a test in a wet salt (NaCl) chamber rusty spots and elongated pits appeared on the brushed surface of a prototype casing for a household device made from AISI 304 stainless steel. The corrosion pits only formed on the brushed surface and on the deformed edges. Metallography revealed deformation-induced martensite and delta ferrite in the mic...

Protective surface layers on AISI 321 stainless steel were prepared by thermal treatments at two different temperatures in air and two controlled atmospheres. Different oxide and/or nitride layers were formed. Surface morphology of the layers was investigated by scanning electron microscopy (SEM). Auger electron spectroscopy (AES) depth profiling o...

Castings made of Al-alloy were after mechanical machining cleaned, wrapped with plastic envelope and stored for two months. During that period, a local corrosion appeared in the form of darker spots on the surface of the castings. Results of XPS investigation of spots on Al-castings are presented. On the surface and in the corrosion products the re...

The surface segregation of copper was investigated in laboratory and industrial non-oriented electrical steel sheets containing copper. The cold-rolled samples of Fe-Si-Al alloys were annealed in the temperature range 320-1 120 K in the ultra-high-vacuum chamber of a field-emission Auger electron spectrometer, and subsequently characterized by Auge...

Within the scope of corporate waste management, Sisak Steelworks initiated a thorough and systematic examination of physical and chemical properties of metallurgical waste and of its behaviour in interaction with the environment. Electric arc furnace (EAF) dust has been categorized as hazardous technological waste and it can not be directly dispose...

Within the scope of corporate waste management, Sisak Steelworks initiated a thorough and systematic examination of physical and chemical properties of metallurgical waste and of its behaviour in interaction with the environment. Electric arc furnace (EAF) dust has been categorized as hazardous technological waste and it can not be directly dispose...

Fe74Si11B14Ni1 soft-magnetic material was prepared as a powder using water atomisation. Using this method, powder particles of less than 45 μm in diameter were obtained after sieving. In the as-water-atomised condition the powder particles were observed to be amorphous. Annealing resulted in the formation of a two-phase nanostructured morphology. T...

The complex nitrides of intermetallics based on titanium, aluminium and nickel are very promising materials for high-performance coatings. Samples of Ni3Al and TiAl3 were prepared by the self-propagating high-temperature synthesis (SHS) of elemental powders in an argon atmosphere with subsequent pulsed-plasma ion nitriding. Results from the combust...

Soft magnetic composites (SMCs) are produced by compressing together soft magnetic powders and a binding insulator material. In some applications these composites are able to replace electrical steel sheets or ferrites. Here we report on the development of an SMC produced from Fe74Si11B14Ni1 alloy powder and a binding epoxy insulator. The Fe74Si11B...

The X20CrMoV121 steels, intended for high-temperature components in power plants, show during thermal and creep exposure in the range of 650 to 800 °C a pronounced change in microstructure. This means that during use in this temperature range virtually all carbon is bound to carbide precipitates. The large particles that at first appear on subgrain...

A soft magnetic composite material was prepared from a commercial, iron-based, soft magnetic powder. Its morphology and composition were examined using SEM, EDS and AES. The flat surface of the sample was found to be of a homogeneous composition, corresponding to the basic soft magnetic powder, whereas phosphorous and zinc were found in the subsurf...

A simple ultrahigh-vacuum-compatible Se deposition source is developed. It consists of a resistively heated crucible enveloped by a copper tube that also has provisions for liquid nitrogen cooling. The temperature of the crucible is measured via an Ni/NiCr thermocouple. All feedthroughs are executed through a CF 70 mm OD flange, which enables the S...

The reconstructed V(1 0 0)-(5×1) surface has been studied by means of the field emission high-resolution Auger electron spectroscopy (HRAES), scanning tunnelling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES) using synchrotron radiation. The obtained HRAES data show that on the nano-meter scale the reconstructed V(1 0 0)-(5×...

Soft magnetic composite (SMC) materials for soft magnetic applications were developed. The most important property of SMC materials, especially those used in a high-frequency range, is that the soft magnetic powder particles are well insulated from each other. Alloy Fe–Si–B powders were prepared by water atomization. The surface of microcrystalline...

A brief review of the high spatial resolution Auger electron spectroscopy (HRAES) and its usage in metallurgy is presented. A combination of HRAES and X-ray photoelectron spectroscopy makes a powerful combination to resolve a large number of problems encountered in metallurgy. Several selected examples of such problems studied in the authors' labor...

The paper presents the results of interracial studies of 19Cr-13Ni austenitic stainless steel doped with 0.26 mass % phosphorus after annealing at 700 and 800°C for 100 and 1000 h by means of high resolution Auger electron spectroscopy (HRAES). After annealing for 100 h the lower than equilibrium concentration of phosphorus at grain boundaries was...

Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to investigate two electrical steel samples prepared by different decarburization treatments. Oxide layers were found on the surfaces of both samples. Cross-sectional analysis of the oxide layers was performed to obtain information about the in-depth distribution of the laye...

Alumina-supported palladium-copper catalysts, which promote liquid-phase nitrate reduction, have been prepared according to different impregnation sequences of γ-Al2O3 support and characterized by X-ray photoelectron spectroscopy (XPS), X-ray induced Auger electron spectroscopy (XAES) and temperature-programmed reduction (TPR). Analysis of Pd XPS/X...

High-resolution Auger electron spectroscopy has been used to study selenium surface segregation on an Se-doped FeSi alloy. The surface segregation of Se and impurities such as C, P and S was measured in situ in the analysis chamber of an Auger spectrometer under ultrahigh vacuum conditions in the temperature range 200–850 °C. At elevated temperatur...

The oxide growth during the decarburization process of non-oriented silicon steel sheets alloyed with 0.5 and 1 mass% of aluminium was studied using high-resolution auger electron spectroscopy (HRAES), the chemical composition was characterized by X-ray photoelectron spectroscopy (XPS). The samples were annealed in a H2–H2O–N2 gas mixture with diff...

The quality of the resulfurized continuous cast steel billets strongly depends on content, distribution and chemical composition of inclusions. High resolution field emission Auger Electron Spectroscopy was used to study the inclusions in steel with 0.035 mas % sulfur and 0.20-0.40 mas % aluminum. For the first time in steel production the chemical...

Scanning tunneling microscopy (STM) was used to study the surface of the 0.1% Sb alloyed electrical steel sheet. Material was subjected to thermal treatment to induce the surface segregation of impurities as well as alloying component. It was found that Fe–S compound formed on the surface. This was determined by direct observation of the compound's...

LiTaO3 thin film from have been obtained by RF-magnetron sputtering from monocrystalline target. The films have been deposited on (111) silicon and platinum without substrate heating. The amorphous films were subsequently annealed in the electric field. The morphology, crystal structure and composition of the films were investigated by means of XRD...

The effect of composition of ZrN and TiN films and deposition temperature on lattice expansion was investigated. ZrN and TiN films containing various at.% of nitrogen were prepared by reactive sputter deposition in a Balzers Sputron plasma beam apparatus. Both ZrN and TiN films were grown at a substrate temperature of 180°C and some of the Zr...

Ferroelectric LiTaO3 thin films were grown using an RF sputtering method from a monocrystalline target on heated substrates of LiTaO3, silicon and sapphire. The structure and composition of obtained films were checked by means of XRD, AES and RBS spectroscopies. The analysis of results showed that the films were preferentially oriented with the c-a...

Three different contact schemes, namely TiSi, TiN0.7Si and TiN/TiSi, were prepared by sputter deposition. The reactions of Ti, TiN/Ti and TiN0.7 films with silicon wafers (100) during vacuum annealing were studied by X-ray diffraction, Auger sputter depth profiling and cross-sectional transmission electron microscopy. The sheet resistance variation...

Three different contact schemes TiSi, TiN0.7Si and TiN/TiSi were prepared by sputter deposition. The reactions of Ti, TiN/Ti and TiN0.7 films with silicon wafers (100) during vacuum annealing were studied. The sheet resistance variation of films was measured for a range of annealing temperatures from 773 to 1123 K. Around 1023 K titanium silicid...

Metallurgical waste management, including the choice of its final disposal, has to be preceded by its characterization. During this process, a series of tests of physical and chemical properties of the waste and of its potential interaction with the environment is conducted. The waste material analysis applies the standard methods and techniques to...