Partner: Maciej Giżyński

Warsaw University of Technology (PL)

Ostatnie publikacje
1.Chrzanowska-Giżyńska J., Denis P., Hoffman J., Giżyński M., Mościcki T., Garbiec D., Szymański Z., Tungsten borides layers deposited by a nanosecond laser pulse, SURFACE AND COATINGS TECHNOLOGY, ISSN: 0257-8972, DOI: 10.1016/j.surfcoat.2017.12.040, Vol.335, pp.181-187, 2018

Streszczenie:

Tungsten borides belong to the group of potentially superhard materials which hardness could be compared to cubic boron nitride and diamond. However, difficulty in fabrication of single phase material using conventional methods is the main drawback of this group of ceramics. In order to overcome this problem material can be deposited as a thin layer e.g. in the pulsed laser deposition process. In this paper, the effect of laser wavelength and energy density of nanosecond Nd:YAG laser on the WBx-type layers were analyzed using wavelengths 355 and 1064 nm with the energy density of laser beam from 1.7 to 5 J/cm2 and from 1.7 to 9.3 J/cm2, respectively. The WB2.5 and WB4.5 targets synthesized in Spark Plasma Sintering process were used and the layers were deposited onto Si (100) substrate heated to a temperature of 570 °C. Layers' microstructure were analyzed using X-ray Diffraction and scanning electron microscope equipped with energy dispersive X-ray spectrometer. Change of laser wavelength and energy density resulted in variations of the chemical composition and morphology of deposited layers. Finally, W2B-βWB, αWB-WB-WB3 and WB3, and boron layers were deposited wherein WB3 structure is formed in a wide range of laser fluences and at both investigated wavelength. Next, WB3 layers were investigated in the indentation test at a load of 5–30 mN and its hardness was up to 50 ± 10 GPa

Słowa kluczowe:

Pulsed laser deposition, Super-hard materials, Tungsten borides, Tungsten triboride

Afiliacje autorów:

Chrzanowska-Giżyńska J.-IPPT PAN
Denis P.-IPPT PAN
Hoffman J.-IPPT PAN
Giżyński M.-Warsaw University of Technology (PL)
Mościcki T.-IPPT PAN
Garbiec D.-Metal Forming Institute, Poznan (PL)
Szymański Z.-IPPT PAN
35p.
2.Chrzanowska J., Kurpaska Ł., Giżyński M., Hoffman J., Szymański Z., Mościcki T., Fabrication and characterization of superhard tungsten boride layers deposited by radio frequency magnetron sputtering, CERAMICS INTERNATIONAL, ISSN: 0272-8842, DOI: 10.1016/j.ceramint.2016.04.166, Vol.42, No.10, pp.12221-12230, 2016

Streszczenie:

The most promising areas of research of new super-hard materials are transition metal borides. These materials are one of the candidates for future superhard layers that will be competitive to DLC and c-BN layers. In this paper MoB-type tungsten boride (WB) layers were examined. WB layers have been deposited by radio frequency magnetron sputtering on Silicon (100), 304 stainless steel (SS 304) and Inconel 601 substrates. Measured thickness of herein prepared layers was about 1 µm, and all studied samples were dense, uniform and smooth. Surface investigation was performed by using an optical profilometer, atomic force microscopy, and scanning electron microscopy. The structure analysis was examined by using X-ray diffractometer (XRD) and transmission electron microscopy (TEM) techniques. Results from the XRD and TEM analysis showed that WB layers were dominated by (101) reflection and indicated a fine grain structure with a grain size of 20–40 nm. The effect of target sputtering power and ambient gas pressure was investigated. The hardness of WB layers deposited on silicon substrate was compared under the load from 1 mN to 5 mN. The hardness of WB layers deposited on SS 304 and Inconel was measured up to 50 mN. All layers of WB revealed excellent hardness exceeding 40 GPa.

Słowa kluczowe:

Borides, Nanohardness, RF magnetron sputtering, Superhard layers, Tungsten boride

Afiliacje autorów:

Chrzanowska J.-IPPT PAN
Kurpaska Ł.-National Centre for Nuclear Research (PL)
Giżyński M.-Warsaw University of Technology (PL)
Hoffman J.-IPPT PAN
Szymański Z.-IPPT PAN
Mościcki T.-IPPT PAN
40p.
3.Chrzanowska J., Hoffman J., Denis P., Giżyński M., Mościcki T., The effect of process parameters on rhenium diboride films deposited by PLD, SURFACE AND COATINGS TECHNOLOGY, ISSN: 0257-8972, DOI: 10.1016/j.surfcoat.2015.07.024, Vol.277, pp.15-22, 2015

Streszczenie:

Rhenium diboride (ReB2) thin films have been deposited by a nanosecond pulsed laser deposition method on Si (100) substrate heated to 570°C. The coatings were formed in the ablation process of SPS sintered ReB2 target. The effect of laser wavelength, energy density and postannealing on the films' properties was studied. Investigated wavelengths were 355 and 1064 nm of Nd:YAG nanosecond laser. Laser beam energy density varied from 2.1 to 6.1 J cm− 2 and from 4.1 to 9.4 J cm− 2 at 355 and 1064 nm, respectively. Layer thickness was of the order of several hundred nanometres. Deposition efficiency increases with an energy density in quasi linear way and strongly grows for shorter wavelength. The layers consist of two characteristic microstructures: a smooth basis and stick debris (typical diameters of several hundred nanometres). Lower energy density of laser beam and longer wavelength favour dominance of smooth basis and minimization of debris. The XRD analysis of all samples indicate the crystalline ReB2 with preferred (002) orientation and fine grain size of about 20 nm. Shorter wavelength and higher energy density foster stronger (002) orientation. Moreover, an annealing right after the deposition (25 min in 350°C) causes minimization of degree of orientation and decrease of hardness. The Vickers hardness of ReB2 films is at about 60 GPa and is reduced to about 40 GPa after the annealing process. Deposition efficiency and physical and chemical structures of layers produced under variety of conditions were studied and compared.

Słowa kluczowe:

Ceramics ablation, Pulsed laser deposition, Rhenium diboride, ReB2 optical properties, Super-hard films, Wavelength influence

Afiliacje autorów:

Chrzanowska J.-IPPT PAN
Hoffman J.-IPPT PAN
Denis P.-IPPT PAN
Giżyński M.-Warsaw University of Technology (PL)
Mościcki T.-IPPT PAN
35p.

Abstrakty konferencyjne
1.Chrzanowska J., Hoffman J., Giżyński M., Mościcki T., Investigation of Wavelength Influence on Rhenium Diboride Films Prepared by PLD Method, INDLAS 2014, 4th International Conference, 2014-05-19/05-23, Bran (RO), pp.24-25, 2014

Streszczenie:

In answer to research interest in production of super hard coatings prepared by pulsed laser deposition (PLD) method, Rhenium Diboride was taken under consideration. PLD is characteristic by necessity to define deposition parameters best for particular substance. ReB2 coatings were prepared with the use of 355 nm and 1064 nm wavelengths of Nd:YAG laser and the influence of laser wavelength on those films preparation was investigated. Deposition efficiency increased with shorter wavelength, however layer’s smoothness was better for longer wavelength. The XRD analysis shows crystalline ReB2 character of achieved samples.

Słowa kluczowe:

pulsed laser deposition, rhenium diboride

Afiliacje autorów:

Chrzanowska J.-IPPT PAN
Hoffman J.-IPPT PAN
Giżyński M.-Warsaw University of Technology (PL)
Mościcki T.-IPPT PAN