Košice, Slovakia
Košice, Slovakia

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Dzupon M.,UMV SAV | Gajdos M.,ELBA | Jurko J.,FVT TU Kosice so sidlom v Presove | Ferdinandy M.,UMV SAV | Jakubeczyova D.,UMV SAV
Chemicke Listy | Year: 2011

The work deals with determining of the size of plastic deformation zone around the surface of drilled holes by means of optical and electron microscopy in austenitic Cr-Ni steel 1.4301. Regions of continuous plastically deformed microstructure and sites under machined surface with plastic deformation localized within isolated austenite grains were identified. Ratio of depth of localized and continuous plastic deformations was 4.5-6.8 for all samples of the 1.4301 material. In the zones of local plastic deformations the values of microhardness were in average 2.5 to 3 times higher than those found outside the plastic deformation zones.


Vyrostkova A.,UMV SAV | Falat L.,UMV SAV | Kepic J.,UMV SAV | Brziak P.,VUZ PI | Pecha J.,SES
METAL 2010 - 19th International Conference on Metallurgy and Materials, Conference Proceedings | Year: 2010

This article deals with investigation focused on microstructure characterisation and fracture behaviour of similar weld-joint of CB2 creep-resistant steel. It is an experimental cast of modified 9%Cr steel investigated in the frame of COST Action 536. The weld joint was prepared by combination of TIG + MMA methods. After the welding postweld-heat-treatment (PWHT) was carried out at 730°C for 24 hours in order to relieve residual stresses and stabilise the microstructure. The weld was investigated in the PWHT state, as well as in isothermally aged states after the annealing at 625°C for 10 000 hours and 30 000 hours, respectively. Microstructure characterisation was performed by light microscopy (LM) and scanning electron microscopy (SEM). The effect of isothermal ageing on mechanical properties at ambient temperature was studied by means of hardness and toughness tests. Microstructure analyses, hardness (HV10) measurements and impact toughness (KV) and fracture toughness (KIC) tests were carried out in the weld joint regions, i.e. heat-affected zone (HAZ), base metal (BM), and weld metal (WM). Fracture surfaces after impact tests were analysed by SEM. © 2010 TANGER Ltd., Ostrava.


Ostroushko D.,VSB - Technical University of Ostrava | Mazancova E.,VSB - Technical University of Ostrava | Saksl K.,UMV SAV | Milkovic O.,Technical University of Košice
METAL 2014 - 23rd International Conference on Metallurgy and Materials, Conference Proceedings | Year: 2014

Surface coatings protection is one of the most important processes ensuring efficient and economic use of basic materials, mostly of lower-quality. At interface of clad and basic material intermetallic phases are formed, representing quite different matrix with dissimilar properties unlike the welded materials. One type of surface coating is explosive bonding which belongs to group of pressure welding. The work is focused on some mechanical properties, micro-hardness in-homogeneities in vicinity of the wave joint both in the basic material and nearby of the Ti and Cr/Ni stainless steel matrix weld line. Investigated weld was both in as-received state and after heat treatment carried out at 600°C/90 minutes/air. The TEM investigation includes a dislocation density and structures in both samples. Phase has been identified by X-ray diffraction performed by synchrotron radiation, and Tiα, Fe-fcc, Fe-bcc and Fe2Ti intermetallic phases were detected at interface area.


Ostroushko D.,VSB - Technical University of Ostrava | Mazancova E.,VSB - Technical University of Ostrava | Saksl K.,UMV SAV | Milkovic O.,Tu kosice
Archives of Metallurgy and Materials | Year: 2014

Surface coatings protection is one of the most important processes ensuring efficient and economic use of basic materials, mostly of lower-quality. At interface of clad and basic material intermetallic phases are formed, representing quite different matrix with dissimilar properties unlike the welded materials. One type of surface coating is explosive bonding which belongs to group of pressure welding. The work is focused on interface shape line, inhomogeneities in vicinity of the wave joint both in basic material and in vicinity of weld line of the Ti and Cr/Ni stainless steel (SS) matrix. Investigated weld was both in as-received state and after heat treatment carried out at 600°C/90 minutes/air. Presented phases have been identified using X-ray diffraction performed by synchrotron. The Tiα, Fe-fcc, Fe-bcc and intermetallic phases Fe2Ti were detected at interface area. © 2014, Committee of Metallurgy, All rights reserved.


Ostroushko D.,VSB - Technical University of Ostrava | Mazancova E.,VSB - Technical University of Ostrava | Saksl K.,UMV SAV | Halgas R.,UMV SAV
Materials Science Forum | Year: 2014

Surface coatings protection is one of the most important processes ensuring efficient and economic use of basic materials, mostly of lower-quality. At interface of clad and basic material intermetallic phases are formed, representing quite different matrix with dissimilar properties unlike the welded materials. One type of surface coating is explosive bonding which belongs to group of pressure welding. The work is focused on some mechanical properties, micro-and nano-hardness controlled by AFM and interface shape line, in homogeneities in vicinity of the wave joint both in the basic material and in vicinity of the Ti and Cr/Ni stainless steel matrix weld line. Investigated weld was both in as-received state and after heat treatment carried out at 600°C/90 minutes/air. Phases has been identified by X-ray diffraction performed BW-5 beamline applying synchrotron radiation, and Tia, Fe-fcc and Fe-bcc were detected at interface area, whereas intermetallic phases were not revealed. © (2014) Trans Tech Publications, Switzerland.

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