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1

Preliminary Structures Assessment of Some TRIP Steels

Pantilimon Mircea Cristian, Berbecaru Andrei-Constantin, Coman George, Sohaciu Mirela G., Dumitrescu Ruxandra Elena, Ciucă Sorin, Gherghescu Ioana-Arina, Predescu Cristian

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 2

491--498

EN

Automotive industry is constantly interested in building cars made of light and high strength parts in order to reduce the emission levels, the fuel consumption and minimize the effects of a car crash. Some parts may be made of lighter materials, but the steel ones must compensate the strength needed for the car body. Research is made for finding new materials showing high strength combined with high ductility. Among them, transformation - induced - plasticity steels are of great interest, efforts being made to improve their characteristics. A new composition of such a steel is presented, its features being compared with those of three other steels of the same class and category. Optical microscopy at different magnifications is performed, together with Vickers hardness test. Structural particularities are found for each tested steel, justified by their own chemical compositions. The new steel reveals important characteristics: besides the mainly bainitic structure, it has both larger ferritic areas and amounts of retained austenite, making him proper for further study.

2

Growth, electrical, thermal, mechanical and etching studies on 4-chloroanilinium hydrogen (2R, 3R)-tartrate monohydrate-an organic NLO single crystal

Sivakumar R., Nadaraj V.

Materials Science Poland

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2019

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Vol. 37, No. 3

310--316

EN

An organic single crystal of 4-chloroanilinium hydrogen (2R,3R)-tartrate monohydrate (4CAHT) was grown by slow evaporation solution growth technique at room temperature. Single crystal XRD study confirmed that the crystal belongs to monoclinic system with the space group P21. Powder XRD analysis confirmed the crystalline nature of the compound. The presence of various functional groups in the compound was revealed by FT-IR analysis. UV studies showed the absence of absorption in the entire visible region. To determine the thermal stability of the grown crystals it was subjected to thermogravimetric and differential thermal analyses. Microhardness and etching studies were also carried out for the crystal. The powder second harmonic generation efficiency of 4CAHT was tested by Kurtz and Perry powder technique and the relative SHG efficiency of 4CAHT was found to be 1.44 times greater than that of standard KDP.

3

Wpływ azotowania jarzeniowego na właściwości powłok stalowych natryskiwanych cieplnie

Babul T., Olbrycht A., Pawlik S., Trojanowski J.

Welding Technology Review

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2018

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R. 90, nr 9

13--18

PL

Technologie hybrydowe to jeden z kierunków rozwoju inżynierii materiałowej. Wpisują się w tę tematykę badania nad poprawą właściwości użytkowych powłok stalowych natryskiwanych cieplnie poprzez obróbkę cieplno-chemiczną. W pracy przedstawiono wyniki badań powłok natryskiwanych łukowo ze stali odpornych na korozję X46Cr13 i X2Cr-Ni18-9 i następnie azotowanych jarzeniowo. Azotowanie jarzeniowe wykonano na potencjale katody przy następujących parametrach: w temperaturze 450 °C przez 6 h i w temperaturze 530 °C przez 4 h. Opisano oraz przedstawiono wyniki następujących badań: badań metalograficznych, analizy punktowej jakościowej i ilościowej EDS, pomiaru twardości HV, rozkładu twardości, pomiaru parametrów chropowatości, badań odporności na zużycie metodą Amslera. W wyniku badań stwierdzono, że azotowanie jarzeniowe powoduje wzrost twardości oraz odporności na zużycie przez tarcie powłok natryskiwanych cieplnie ze stali odpornych na korozję X46Cr13 i X2CrNi18-9. Technologia hybrydowa łącząca natryskiwanie cieplne stali odpornej na korozję martenzytycznej X46Cr13 i azotowanie jarzeniowe w temperaturze 530 °C przez 4 h zapewnia wytworzenie powłoki o najwyższej twardości i odporności na zużycie ze wszystkich badanych powłok. Powłoka taka może zostać zastosowana do regeneracji części maszyn, od których wymaga się szczególnie wysokich właściwości użytkowych.

EN

Hybrid technologies are one of the directions of materials engineering development. They contribute to the subject of research on improving the performance of thermally sprayed steel coatings by thermo-chemical treatment. The paper presents the test results of arc spraying stainless steel coatings and then glow-discharge nitrided. The glow-discharge nitriding was performed with the following parameters: at 450 °C for 6 hours and at 530 °C for 4 hours. The results of the following tests are described and presented: metallographic (SEM), qualitative and quantitative analysis point EDS, measurement of hardness HV, hardness distribution, measurement of roughness parameters (Ra, Rz), wear resistance by the Amsler method. The results showed that the glow-discharge nitriding increases the hardness and the frictional wear resistance of thermal sprayed stainless steel X46Cr13 and X2CrNi18-9 coatings. The hybrid technology, combining thermal spraying of martensitic stainless steel X46Cr13 and glow-discharge nitriding at 530 °C for 4 hours, provides formation of a coating with the highest hardness and wear resistance of all the tested coatings. This coating can be applied to the regeneration of machine parts, which are required to have particularly high useful properties.

4

Influence of TiN nanoparticles on the microstructure and hardness of arc overlaid welding layers

Kondov H., Tashev P.

Prace Instytutu Odlewnictwa

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2017

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Vol. 57, no. 4

309--314

EN

Electrodes for manual arc overlay welding with coating containing nanomodifier TiN in concentrations between 0.2% and 1.5% were developed and manufactured. Samples of welded overlay layers with electrodes were both examined by electron microscopy and X-ray microanalysis. Some samples were subjected to heat treatment consisting of annealing and subsequent hardening in water and oil. The Vickers hardness HV15/15 of the samples in the prepared state, and both after annealing and hardening were measured. It was found that growth of the hardness of nanomodified layers were up to 180 percent compared to the reference sample.

5

Mechanical properties of ZrO2-Ti composite system

Łada P. M., Lewandowska D., Miazga A., Konopka K.

Composites Theory and Practice

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2017

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R. 17, nr 1

3--8

EN

The paper presents the characteristics of the ZrO2-Ti composite system, formed by the slip casting method. Samples were prepared from slurries with a 45 vol.% solid phase content and 0, 3 and 10 vol.% additions of titanium, respectively. The sintering process was executed in the inert atmosphere of argon at 1450°C with a 2-hour dwell time at the maximum temperature. Density and strength measurements of the green bodies and sintered samples were made. In order to determine the phase structures before and after the sintering process, X-ray analysis was conducted. Vickers hardness and fracture toughness for the sinters were measured. The addition of titanium particles to ZrO2 resulted in a slight decrease in hardness compared to the plain zirconia samples, while the fracture toughness of the composite samples increased. The tensile strength of the green bodies and sinters was at a similar level for the zirconia and composite samples. For the green bodies, the monoclinic ZrO2 phase and tetragonal ZrO2 were revealed. After sintering, only the tetragonal phase of zirconia was detected.

PL

Przedstawiono wybrane właściwości mechaniczne kompozytów z układu ZrO2-Ti wytwarzanych metodą odlewania z mas lejnych (ang. slip casting). W celu wykonania próbek przygotowano masy o zawartości 45% obj. fazy stałej z dodatkiem tytanu w ilości 0, 3 i 10% objętościowych. Badania zagęszczenia oraz wytrzymałości przeprowadzono na próbkach w stanie surowym oraz próbkach po spieczeniu w temperaturze 1450°C w atmosferze obojętnej argonu. W celu określenia budowy fazowej przeprowadzono badanie XRD dla próbek przed i po spieczeniu. Wykonano także pomiary twardości metodą Vickersa. Na ich podstawie wyliczono odporność na kruche pękanie. Dodatek tytanu spowodował nieznaczne obniżenie twardości przy wzroście odporności na kruche pękanie w stosunku do ceramiki cyrkonowej, nie zmienił za to wytrzymałości kształtek w stanie surowym. W próbkach przed spieczeniem zaobserwowano występowanie fazy jednoskośnej ZrO2, która nie pojawia się w próbkach po spieczeniu.

6

Thermal and mechanical characterization of zirconium based LPPS coatings on glass

Drajewicz M.

Advances in Manufacturing Science and Technology

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2017

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Vol. 41, nr 4

31--40

EN

The basic factor limiting the use of glasses is their unsatisfactory mechanical strength. The improvement of the mechanical strength of glasses is usually obtained by applying their respective thin surface layers. The object of the research was glass coated with zirconium oxide. For the application of zirconium oxide layer, LPPS (Low Pressure Plasma Spraying) method was used. The resulting materials were subjected to detailed examination of the thermal properties (cp-DSC, dilatometer, laser flash analysis), and mechanical tests (Vickers hardness and modulus of elasticity). The study showed that the obtained LPPS layer of zirconium oxide (IV) on glasses influence the improvement of the mechanical properties. It has been shown that the applied layers have high adhesion to the substrate.

PL

Właściwości mechaniczne szkła decydują o ich rozwoju i zastosowaniu w technice. Ograniczają jednak często wciąż ich właściwości użytkowe. Szczególnie dotyczy to właściwości, które zależą od składu fazowego i budowy warstwy wierzchniej szkła. Stąd poprawę tych właściwości szkła, zwłaszcza wytrzymałościowych, obecnie uzyskuje się przez modyfikowanie ich warstwy wierzchniej lub konstytuowanie nowej warstwy na podłożu szkła, m.in przez wytworzenie cienkiej warstwy tlenkowej metodami inżynierii powierzchni. W niniejszej pracy przyjęto założenie, że zastosowanie stabilizowanego tlenku ZrO2 w procesie fizycznego osadzania z fazy gazowej w warunkach obniżonego ciśnienia pozwoli na wytworzenie stabilnej warstwy wierzchniej na podłożu szkła. Założono, że wytworzona warstwa zapewni również zwiększenie efektu umocnienia szkła krzemianowo – sodowo – wapiennego. Wykonano pomiary właściwości cieplnych i wytrzymałościowych oraz przeprowadzono analizy uzyskanych wyników.

7

Wpływ zawartości kobaltu na właściwości powłok WC-Co natryskiwanych naddźwiękowo

Olbrycht A., Pawlik S.

Inżynieria Powierzchni

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2016

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nr 3

45--53

PL

W pracy przedstawiono wyniki badań powłok WC-Co natryskiwanych metodą płomieniowa naddźwiękową z proszków o zawartości kobaltu 12 i 17%. Zbadano wpływ wielkości ziarna natryskiwanego proszku WC-Co na właściwości powłok. Opisano oraz przedstawiono wyniki badań: metalograficznych, twardości HV, metodą DSI (Depth Sensing Indentation), zarysowania (scratch test), przyczepności oraz twardości Rockwella HRC. Stwierdzono, że w wyniku natryskiwania cieplnego metodą naddźwiękową proszków WC-Co otrzymano powłoki o zwartej budowie, nieznacznej porowatości oraz dobrej przyczepności do podłoża. Powłoki natryskiwane naddźwiękowo z proszku o wyższej zawartości Co 17% mają wyższą twardość (zmierzoną metodą DSI na powierzchni powłoki), niż powłoki natryskane cieplnie z proszku o zawartości 12% Co. Najwyższą średnią wartość modułu Younga odnotowano w przypadku powłoki natryskanej z proszku WC-17Co (-20+5 µm), powłoka ta ma również najwyższe twardości mierzone metoda DSI: indentacyjną, Martensa oraz Yickersa.

EN

The paper presents the results of the examinations of WC-Co coatings sprayed by high velocity flame method with powder containing different amounts of cobalt. The impact of particle size of the sprayed WC-Co powder on the properties of the coatings was also examined. The paper describes and presents the results of the following te.sts: metallographic tests, hardness measurement HV, testing by DSI method (Depth Sensing Indentation), scratch test, adhesion test and measurement of Rockwell hardness HRC. It was found that by supersonic thermal spraying with WC-Co powders with different content of Co and with various particle sizes, the, coatings of compact structure, slight porosity and a very good adhesion to the substrate were obtained. It was also found that the thermally sprayed coatings with the powder with a higher Co content, ie. 17% have higher hardness, as measured by the DSI method, on the surface of the coating than the coatings sprayed thermally with the powder containing 12% Co. The highest average vahic of Young's modults was observed for the coating sprayed with the WC-Co83/l7 (-20-5 µm) powder, this coating has also the highest hardness measured by DSI method: indentation hardness, Martens hardness and Yickers hardness.

8

The Impact of Damage in Anneling Inconel 718 on Hardness Measured by the Vickers Method

Malicki M., Gadalińska E., Chmiel M.

Fatigue of Aircraft Structures

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2016

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Iss. 8

92--96

EN

In the previous work [1] it was shown that strain hardening had considerable impact on the hardness of Inconel 718. In order to verify the weakening of the material associated with the damage mechanism in the tested material, the hardness tests were performed on the stretched specimen which was subsequently heat treated. The tests revealed that, after heat treatment, the measured hardness was reduced with an increasing degree of the plastic deformation present prior to heat treatment.

9

Optical and Mechanical Characterization of Zirconium Based Sol-Gel Coatings on Glass

Sitarz M., Drajewicz M., Jadach R., Długoń E., Leśniak M., Reben M., Wajda A., Gawęda M., Burtan-Gwizdała B.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

1747--1752

EN

The basic factor limiting the use of glasses is their unsatisfactory mechanical strength. The improvement of the mechanical strength of glasses is usually obtained by applying their respective thin surface layers. The object of the research was glass coated with zirconium oxide. For the application of zirconium oxide layer, dip-coating method was used. The resulting materials were subjected to detailed examination of the microstructure (SEM), and mechanical tests (Vickers hardness and modulus of elasticity). In order to evaluate the optical characteristics, the tests were performed by UV/VIS. The thickness of the overlying layers were determined using the method of ellipsometry. The study showed that the obtained sol-gel layer of zirconium oxide (IV) on glasses influence the improvement of the mechanical properties. It has been shown that the applied layers have high adhesion to the substrate.

10

Hydrostatic extrusion of Al coated titanium obtained by the magnetron technique

Pachla W., Kulczyk M., Skiba J., Przybysz S., Czyżniewski A., Betiuk M.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 68, nr 1

25--31

EN

Purpose: The paper synthetically presents the ideas of hydrostatic extrusion of metals in order to obtain strong refinement of their structure. It seems that modification of extruded material and the surfaces of dies may be one of the methods for limiting these adverse phenomena. The paper describes the role of lubricating the Al layer during the titanium extrusion process. Design/methodology/approach: Studies concerning this technique are conducted at The Polish Academy of Sciences Institute of High Pressure Physics. Due to strong plastic deformations (SPD), the cumulative hydrostatic extrusion (HE) process must be used, i.e. the process of step-by-step extrusion with low deformation ratio for each step, the deformations created in each step accumulate and result in strong cumulative deformation. Findings: This is because the available working pressures of extrusion presses are limited, thus limiting the maximum deformation ratio available in a single extrusion pass. This limitation is additionally sharpened by higher strength of material deformed in cold state or at low temperatures. Research limitations/implications: Due to tribological conditions existing between the extruding tool (a die) and the flowing material, the die becomes worn quickly and the finishing quality (roughness) of the extruded material surface deteriorates. Practical implications: As a result, the extruding pressure increases which has a negative impact, the machine and tooling load becomes higher and the phenomenon of abrupt outflow of the material being extruded from the extruding tool occurs, causing poor tolerances of lateral dimensions of the product. Originality/value: The process of depositing Al coatings on cylindrical surfaces of titanium material being extruded using the PA PVD technique was presented in detail. Also, the paper describes examinations of Al coating properties and structure of Grade 3 titanium in subsequent steps of hydrostatic extrusion process.

11

The Impact of Damage in Inconel 718 on Hardness Measured by the Vickers Method

Malicki M., Madejski B.

Fatigue of Aircraft Structures

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2015

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Iss. 7

69--79

EN

To prevent failure of machine components it is necessary to measure material damage generated in a component throughout its entire lifetime. Damage can be quantified by means of damage parameters. This paper considers the usefulness of hardness measurements to evaluate damage parameter in Inconel 718. Vickers hardness tests were performed on a specimen with a variable cross section area after tensile testing. The specimen’s geometry enabled the evaluation of damage parameter in respect of hardness measurements made on one individual specimen.