Arkadiusz Krajewski

Prof. Dr. Arkadiusz Krajewski

orcid

Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 December 2012 in Bulletin Of The Polish Academy Of Sciences-Technical Sciences
Verified
Journal Article
Open access
PDF file
AKArkadiusz Krajewski
Arkadiusz Krajewski
WWW. Włosiński
W. Włosiński
Tomasz M. ChmielewskiTomasz M. Chmielewski
Tomasz M. Chmielewski
PKPaweł Kołodziejczak
Paweł Kołodziejczak
The structure and hardness of the surface-welds and fusion-welds made on a 2017A aluminum alloy waveguide using the MIG and TIG methods with and without the participation of ultrasonic vibrations were examined. Cross-sections of the fusions and surface-welds thus obtained were observed in a microscope and the hardness distributions were determined. The aim of the study was to analyze the effects of the ultrasonic vibrations applied to the melted metal pool by a vibrating substrate which in our experiments was a waveguide. The interactions of the ultrasonic vibrations with the molten metal during its solidification and also with the heat-affected zone were examined at various phases of the vibration wave. The ultrasonic vibrations affected the structure of a weld. These changes are strongly depended on the wave phase.

1 March 2003 in Vacuum
Verified
Journal Article
Closed access
JPJ. Piekoszewski
J. Piekoszewski
AKArkadiusz Krajewski
Arkadiusz Krajewski
FPF. Prokert
F. Prokert
JSJ. Senkara
J. Senkara
JSJ. Stanisławski
J. Stanisławski
WWW. Włosiński
W. Włosiński

10 December 2019 in Coatings
Verified
Journal Article
Open access
PDF file
Tomasz M. ChmielewskiTomasz M. Chmielewski
Tomasz M. Chmielewski
MHMichał Hudycz
Michał Hudycz
AKArkadiusz Krajewski
Arkadiusz Krajewski
Tadeusz SalacinskiTadeusz Salacinski
Tadeusz Salacinski
BSBeata Skowrońska
Beata Skowrońska
Rafał ŚwierczRafał Świercz
Rafał Świercz
The article presents selected properties of a titanium metallization coating deposited on aluminum nitride (AlN) ceramics surface by means of the friction surfacing method. Its mechanism is based on the formation of a joint between the surface of an AlN ceramics substrate and a thin Ti coating, involving a kinetic energy of friction, which is directly converted into heat and delivered in a precisely defined quantity to the resulting joint. The largest effects on the final properties of the obtained coating include the high affinity of titanium for oxygen and nitrogen and a relatively high temperature for the deposition process. The titanium metallization coating was characterized in terms of surface stereometric structure, thickness, surface morphology, metallographic microstructural properties, and phase structure. The titanium coating has a thickness ranging from 3 to 7 μm. The phase structure of the coating surface (XPS investigated) is dominated by TiNxOy with the presence of TiOx, TiN, metallic Ti, and AlN. The phase structure deeper below the surface (XRD investigated) is dominated by metallic Ti with additional AlN particles originating from the ceramic substrate due to friction by titanium tools.

21 April 2015 in Welding International
Verified
Journal Article
Closed access
AKArkadiusz Krajewski
Arkadiusz Krajewski
This article presents the current state of knowledge on the issue of supporting classic welding processes by mechanical vibrations. Selected results of own research on the impact of mechanical vibration on the structure and properties of welding structures are also discussed.

19 January 2024 in Materials
Verified
Journal Article
Open access
PDF file
DMDamian Markuszewski
Damian Markuszewski
MWMariusz Wądołowski
Mariusz Wądołowski
AKArkadiusz Krajewski
Arkadiusz Krajewski
The purpose of this study is to investigate the dynamic properties of new structures formed by combining carbon fiber and epoxy resin-based composite materials with SMA (shape memory alloy) “smart materials” in the form of NiTiNol wire. Such a combination will have an impact on the dynamics of the structure, especially in terms of stiffness controllability. Key mechanical parameters such as natural frequency and stiffness, as well as the effect of temperature, were determined through experimental studies.

20 September 2020 in Materials
Verified
Journal Article
Open access
PDF file
AKArkadiusz Krajewski
Arkadiusz Krajewski
GKGrzegorz Klekot
Grzegorz Klekot
MCMarcin Cybulak
Marcin Cybulak
PKPaweł Kołodziejczak
Paweł Kołodziejczak
The research described in this article presents a new contactless method of introducing mechanical vibrations into the base material during CO2 laser welding of low-carbon steel. The experimental procedure boiled down to subjecting a P235GH steel pipe with a 60 mm diameter, 3.2 mm wall thickness and 500 mm length to acoustic signals with a resonant frequency during the welding process. Acoustic vibrations with a frequency of 1385, 110 and 50 Hz were introduced into the pipe along the axis and transversely from the outer surface. The obtained welds were then subjected to structural tests and Vickers hardness measurements. The results of comparative tests show the impact of such introduced vibrations on the granular structure of the welds, as well as on their microhardness in specific areas, such as the face, penetration depth and the heat-affected zone. The effectiveness of the proposed method of introducing vibrations in the scope of grain size and shape as well as changes in the hardness distribution in the obtained welds is demonstrated.