Wyniki wyszukiwania - Biblioteka Nauki

1

Centrum kompetencji TP dla operatorów Grupy France Telecom

100%

Adamiak M.

|

tom nr 4

118-119

PL

Omówiono temat centralizacji nadzoru nad siecią TP oraz jej elementami. Wiedza ekspercka pracowników TP zdobyta podczas tego procesu wpłynęła na wdrożenie w TP operacyjnych centrów kompetencji, świadczących usługi nie tylko w Polsce, ale również w innych krajach Grupy FT

EN

The article covers issues of supervision centralization over TP network and its network elements. As a next step aiming for maximal use of specialists' knowledge TP presents a project of implementing Operations Skill Centers at TP, which provide services not only in Poland, but also in other countries of FT Group.

2

Selected properties of the aluminium alloy base composites reinforced with intermetallic particles

100%

Adamiak M.

|

tom Vol. 14, nr 1-2

43--47

EN

Purpose: The main aim of this work is to investigate two types of intermetallics TiAl and Ti3Al as reinforcement and their influence on selected properties and microstructure of aluminium matrix composites. Design/methodology/approach: Aluminium matrix composites were produced employing the atomised aluminium alloy AA6061 as metal matrix, when as reinforcement TiAl and Ti3Al intermetallics particles were used. The powders were cold pressed and then hot extruded. To evaluate the effect of mechanical milling two types of ball mills were used: a low energy (horizontal ball mill) and a high energy one (eccentric ball mill). Reinforcement contents for both processes 5, 10, 15 % by weight. To determine hardness Vickers tests were performed. Microstructure observations were made by optical microscopy and scanning electron microscopy SEM. Findings: Based on the examinations carried out one can state that the mechanical milling can produce composites powders with homogenous distribution of reinforcement particles. The mechanically milled and extruded composites show finer and better distribution of reinforcement particles what leads to better mechanical properties of obtained products. Research limitations/implications: In order to evaluate with more detail the possibility of applying these composite materials at practical application, further investigations should be concentrated on the interface reaction of the matrix and reinforcing particles during elevated temperature exposition and their influence on mechanical properties. Practical implications: The composites materials produced by this way have shown significant improvement of the mechanical properties in comparision with matrix materials. Good properties of the composites make them suitable for various technical and industrial applications. Originality/value: It should be stressed that the materials as intermetallic compounds with outstanding mechanical properties and good thermal stability were developed making them a powerful material to be used in this kind of composites as the alternative for the reinforcements usually investigated and utilized to the composites materials production - alumina or silicon carbide.

3

Zastosowanie mechanicznego mielenia do wytwarzania materiałów kompozytowych

100%

Adamiak M.

Archiwum Odlewnictwa

|

2006

|

tom R. 6, nr 21/2

361--368

PL

W ramach pracy wykonano badania nad możliwością wytwarzania materiałów kompozytowych o osnowie stopu aluminium EN AW6061 wzmacnianych cząstkami fazy międzymetalicznej Ti3Al w procesie mechanicznego mielenia, a następnie prasowania proszków i wyciskania na gorąco. Stwierdzono, że zmieniając czas trwania procesu mechanicznego mielenia w zasadniczy sposób oddziałuje się na morfologię materiałów proszkowych, uzyskując zmianę ich morfologii ze sferycznej charakterystycznej dla stanu wyjściowego w odkształconą plastycznie - płatkową, która następnie w powtarzających się procesach zgrzewania i pękania materiału umocnionego ponownie przyjmuje postać cząstek równoosiowych. Wytworzone materiały kompozytowe charakteryzują się równomiernym rozłożeniem rozdrobnionych cząstek wzmacniających wpływającym na podwyższenie własności mechanicznych. Mechaniczne mielenie proszków wyjściowych z utworzeniem proszków kompozytowych poprzez rozdrobnienie mikrostruktury w połączeniu z dyspersyjnym umocnieniem materiału od cząstek wzmacniających powoduje dwukrotny wzrost twardości w odniesieniu do materiału osnowy, także prowadzi do znaczącej poprawy własności mechanicznych. Materiały kompozytowe z 15% wagowym udziałem cząstek Ti3Al osiągają wytrzymałość na rozciąganie Rm ok. 400 MPa.

EN

The present work investigates the production of aluminium EN AW6061 matrix composite materials reinforced with Ti3Al particles by mechanical milling followed by powder metallurgy techniques and hot extrusion. It was find out that mechanical milling process has a big influence on the characteristics of powder materials, changing the spherical morphology of as-received powder, during milling process to flattened one due to particle deformation, followed by welding and fracturing particles of deformed and hardened enough which allows to receive equiaxial particles morphology again. The mechanically milled and extruded composites show finer and better distribution of reinforcement particles what leads to better mechanical properties of obtained products. The hardness increases twice in case of mechanically milled and hot extruded composites. The finer microstructure increase mechanical properties of composites materials. The higher reinforcement content results in higher particles dispersion hardening. Composites reinforced with 15% of Ti3Al reach about 400 MPa UTS.

4

Structure and properties of TiN and Ti(C,N) coatings on Co high-speed steels.

63%

Dobrzański L. A. , Adamiak M.

Inżynieria Materiałowa

|

1998

|

tom R. XIX, nr 4

986-987

EN

The paper present results of investigations of the type base material of the W-Mo-V-Co+Si, with economically adjusted chemical composition on structure and properties of hard, wear resistant coatings of titanium nitride TiN and titanium carbonitride Ti(C,N), deposited in the PVD process. It was shown that high-speed steels containing 9%-11% tungsten, 2% molybdenum and limited the Co concentration from 10% to about 5%, coated in the PVD process expose properties comparable with the ones obtained on the others high-speed steels grades. This makes it possible to employ in practice the high-speed steels with relatively low concentration of the alloying elements instead of the high-alloy cobalt steels, provided the base heat treatment is carried out so that it ensures the maximum secondary hardness.

5

Zgrzewanie oporowe zwarciowe materiałów kompozytowych wzmocnionych cząstkami fazy międzymetalicznej

63%

Górka J. , Adamiak M.

|

tom z. 66 [227]

83-92

PL

W artykule przedstawiono wyniki badań procesu zgrzewania oporowego zwarciowego materiału kompozytowego na osnowie stopu aluminium zbrojonego cząstkami fazy międzymetalicznej Ti3Al. Przeprowadzone próby zgrzewania. badania wytrzymałości, pomiary twardości oraz badania metalograficzne wykazaly, że istnieje możliwość otrzymania połączeń o wytrzymałości 80 % wytrzymałości materialu rodzimego, przy zastosowaniu miękkich parametrów zgrzewania. Proces zgrzewania zwarciowego kompozytu zbrojonego Ti3AI powoduje zmiękczenie obszaru zgrzewania, co spowodowane jest prawdopodobnie przestarzeniem materiału osnowy. W celu poprawy własności wytrzymałościowych złącza, konieczne jest przeprowadzenie obróbki cieplnej po zgrzewaniu.

EN

The present work investigates the feasibility of joining the aluminium AA6061 matrix composite materiaIs reinforced with Ti3Al particles by the resistance butt welding. Results of investigation carried out shows that the best mechanical properties of joints can be achieved by applying soft conditions of butt welding process e.g. current 1300 A and current jlow time 1,2 s. To improve hardness and tensile properties of butt welding joints age hardening is necessary.

6

Charakterystyka przeciwzużyciowych powłok PVD przeznaczonych do pracy w podwyższonej temperaturze naniesionych na podłoże ze stali X37CrMoV5-1

51%

Polok M. , Adamiak M. , Dobrzański L. A.

|

tom Z. 82

127-134

PL

W artykule przedstawiono charakterystykę przeciwzużyciowych powłok PVD TiN i CrN oraz TiN/(Ti, Al)N naniesionych na podloże ze stali narzędziowej do pracy na gorąco typu X37CrMoV5-1. Obserwacje przełomów badanych powłok pozwalaja stwierdzić, że powłoki TiN, TiN/(Ti,Al)N charakteryzują się zwartą, kolumnową strukturą, podczas gdy powłoka CrN charkteryzuje się zwartą budową submikrokrystaliczną. Rentgenowska ilościowa analiza fazowa pozwala stwierdzić uprzywilejowaną orientację krystalograficzną (111) dla powłoki monowarstwowej TiN oraz multiwarstwowej TiN/(Ti, Al)N. Na podstawie przeprowadzonego testu na zarysowanie (scratch testu) stwierdzono, że najlepszą przyczepnością charakteryzuje się powłoka CrN, a najgorszą TiN/(Ti,Al)N.

EN

The paper presents characterization of antiwear PVD coatings TiN, CrN and TiN/(Ti, Al)N types deposited onto X37CrMoV5-1 type hot work tool steel. Mrtallographic examinations of coating fractures show that TiN, TiN/(Ti, Al)N coatingshave compacted, column structure, while CrN coating has compacted submicrocrystalline structure. The X-ray quantitative phase analysis makes it possible to find out the privileged crystallographic orientation (111) for the monolayer TiN coating and for the multilayer TiN/(Ti, Al)N one. Based on carried out scratch test it was found that the highest adhesion among investigated coatings presents CrN coating and the lowest one TiN/(Ti, Al)N coatings.

7

Odporność na zużycie ścierne materiałów kompozytowych o osnowie stopu EN AW-AlCu4Mg1 (A) wzmacnianych cząstkami Al2O3 lub Ti(C,N)

51%

Dobrzański L. A. , Włodarczyk-Fligier A. , Adamiak M. , Krupiński M.

Inżynieria Materiałowa

|

2006

|

tom Vol. 27, nr 3

135-138

PL

W pracy przedstawiono wyniki badań odporności na zużycie ścierne materiałów kompozytowych o osnowie stopu aluminium EN A W -AlCu4Mg1(A) wzmacnianych cząstkami faz Ti(C,N) lub Al2O3 o różnym udziale masowym. Badania zrealizowano zarówno dla materiałów obrobionych cieplnie jak również bez takiej obróbki - bezpośrednio po wyciskaniu na gorąco. Analiza wyników wskazuje, że odporność na zużycie badanych materiałów kompozytowych zależy od rodzaju, wielkości i udziału masowego cząstek wzmacniających, a także od stanu, w jakim były badane. Najmniejszym ubytkiem masy po badaniach odporności na zużycie charakteryzował sie materiał kompozytowy wzmocniony cząstkami Ti(C,N). Wraz ze wzrostem udziału tych cząstek w osnowie, ubytek masy materiału kompozytowego maleje. Podobnie utwardzanie wydzieleniowe powoduje poprawę odporności na zużycie badanych materiałów kompozytowych.

EN

The paper presents results of wear resistance investigations of aluminium alloy EN AW-AlCu4Mg1 (A) base composite materials reinforced with different mass concentration of Al2O3 or Ti(C,N) particles. Investigations were made on heat treated materials as well as not heat treated ones – as received after hot extrusion. Results analysis indicates that wear resistance of investigated materials depends on type, size and mass volume of reinforcing particles and heat treatment state. The lowest mass decrement after wear tests characterize composites materials reinforced with Ti(C,N) particles. The mass decrement of composite materials reinforced with that type of reinforcing particles become smaller with their concentration grow. Similar effect of composite materials wear resistance grow can be observed after their age hardening heat treatment.

8

Mechanically milled aluminium matrix composites reinforced with halloysite nanotubes

51%

Dobrzański L. A. , Tomiczek B. , Adamiak M. , Gołombek K.

|

2012

|

tom Vol. 55, nr 2

654--660

EN

Purpose: The present work describes fabrication of aluminium AlMg1SiCu matrix composite materials reinforced with halloysite nanotubes by powder metallurgy techniques and hot extrusion. Design/methodology/approach: Mechanical milling, compacting and hot extrusion successively are considering as a method for manufacturing metal composite powders with a controlled fine microstructure and enhanced mechanical properties. It is possible by the repeated welding and fracturing of powders particles mixture in a highly energetic ball mill. Findings: The milling process has a huge influence on the properties of powder materials, changing the spherical morphology of as-received powder during milling process to flattened one due to particle deformation followed by welding and fracturing particles of deformed and hardened enough which allows to receive equiaxial particles morphology again. The investigation shows that so called brittle mineral particles yields to plastic deformation as good as ductile aluminium alloy particles. That indicates that the halloysite powder can play a role of the accelerator during mechanical milling. High energy ball milling as a method of mechanical milling improves the distribution of the halloysite reinforcing particles throughout the aluminium matrix, simultaneously reducing the size of particles. The apparent density changes versus milling time can be used to control the composite powders production by mechanical milling and the presence of halloysite reinforcements particles accelerates the mechanical milling process. Research limitations/implications: Contributes to knowledge about technology, structure and properties of aluminium alloy matrix composite material reinforced with mineral nanoparticles. Practical implications: Conducted research shows that applied technology allows obtaining very good microstructural characteristics. Originality/value: It has been confirmed that halloysite nanotubes can be applied as an effective reinforcement in the aluminium matrix composites. Deformation, grain size reduction and dispersion conduce to hardening of the composite powders. Mechanical milling cause a high degree of deformation, decrease the grain size even to nanoscale and create an enormously uniform distribution of reinforcing phases or oxides in the structure of the metal.

9

Comparison of abrasion resistance of selected constructional materials

51%

Adamiak M. , Górka J. , Kik T.

Journal of Achievements in Materials and Manufacturing Engineering

|

2009

|

tom Vol. 37, nr 2

375-380

EN

Purpose: The aim of this work was to define and compare abrasion resistance of selected constructional materials widely used in the industry. Chromium cast iron wear resistant plates were compared with typically used wear resistant plates made from Hardox 400 steel and two different, wear resistant, materials cladded by welding technologies. Design/methodology/approach: The tests of abrasive wear were conducted in accordance to procedure “A” of standard ASTM G 65 - Standard Test Method for Measuring Abrasion Using the Dry Sand/Rubber Wheel Apparatus. Findings: Abrasion resistance tests shows that the best properties among investigated samples has chromium cast iron plate. Abrasion wear resistance of this plate is two times higher than wear resistance of layer made by welding technologies and nine times higher than typical Hardox 400 steel plate. Practical implications: Application, of abrasion resistant materials, results in significant material and economy savings, due to wear and costs reduction (decreasing stop times needed to change worn parts for a new one). Originality/value: Wear plates are modern solution in regeneration of worn machines parts and also for producing a new parts which connect high wear and abrasion resistance with costs reduction.

10

Joining of the AMC Composites Reinforced with Ti3Al Intermetallic Particles by Resistance Butt Welding

51%

Adamiak M. , Tomiczek B. , Górka J. , Czupryński A.

|

nr 2

11

Influence of heat treatment on properties and corrosion resistance of Al-composite

51%

Włodarczyk-Fligier A. , Dobrzański L. A. , Adamiak M.

Journal of Achievements in Materials and Manufacturing Engineering

|

2007

|

tom Vol. 21, nr 1

55-58

EN

Purpose: of the project was evaluation of the effect of heat treatment and of the reinforcing Al2O3 particles in the EN AW-AlCu4Mg1(A) aluminium alloy on the mechanical properties, abrasive and corrosion resistance in the NaCl water solution environment. Design/methodology/approach: some of the composite materials were hyperquenched for 0.5 h at the temperature of 495 degrees centigrade with the subsequent cooling in water, and were quench aged next for 6 h at 200 degrees centigrade. Hardness tests were made on HAUSER hardness tester with the Vickers method at 10 N. Static compression and tensile tests of the fabricated composite materials were made on the ZWICK 100 type testing machine at room temperature. Abrasion resistance wear tests were carried out with the constant number of cycles of 5000 (120 m) at various loads: 4, 5, 6, 7, and 8 N. Test pieces were rinsed in the ultrasonic washer to clean them and next weighed on the analytical balance with the accuracy of 0.0001 g to check the mass loss. Corrosion tests were made in 5% water NaCl solution. Findings: Besides visible improvement of mechanical properties: hardness, compression strength and tensile strength, wear resistance there were also observed the influence of heat treatment on the corrosion resistance of composite materials in 3% NaCl solution. Practical implications: Tested composite materials can be applicate among the others in automotive industry but it requires additional researches. Originality/value: It was demonstrated that the mechanical properties, as well as the wear and corrosion resistance of the sintered composite materials with the EN AW-Al Cu4Mg1(A) alloy matrix may be formed by the dispersion hardening with the Al2O3 particles in various portions and by the precipitation hardening of the matrix.

12

A Study of Susceptibility and Evaluation of Causes of Cracks Formation in Braze-Weld Filler Metal in Lap Joints Aluminum – Carbon Steel Made with Use of CMT Method and High Power Diode Laser

51%

Górka J. , Adamiak M. , Wyględacz B. , Czupryński A.

|

tom 62

|

nr 4

13

Joining of the AMC Composites Reinforced with Ti3Al Intermetallic Particles by Resistance Butt Welding

51%

Adamiak M. , Tomiczek B. , Górka J. , Czupryński A.

Archives of Metallurgy and Materials

|

2016

|

tom Vol. 61, iss. 2A

847--852

EN

The introduction of new reinforcing materials continues to be investigated to improve the final behaviour of AMCs as well as to avoid some drawbacks of using ceramics as reinforcement. The present work investigates the structure, properties and ability of joining aluminium EN-AW 6061 matrix composite materials reinforced with Ti3Al particles by resistance butt welding as well as composite materials produced by mechanical milling, powder metallurgy and hot extrusion techniques. Mechanically milled and extruded composites show finer and better distribution of reinforcement particles, which leads to better mechanical properties of the obtained products. Finer microstructure improves mechanical properties of obtained composites. The hardness increases twice in the case of mechanically milled composites also, a higher reinforcement content results in higher particle dispersion hardening, for 15 wt.% of intermetallics reinforcement concentration composites reach about 400 MPa UTS. Investigation results of joints show that best hardness and tensile properties of joints can be achieved by altering soft conditions of butt welding process e.g. current flow time 1.2 s and current 1400 A. To improve mechanical properties of butt welding joints age hardening techniques can also be used.

14

Manufacturing of EN AW6061 matrix composites reinforced by halloysite nanotubes

51%

Dobrzański L. A. , Tomiczek B. , Adamiak M.

Journal of Achievements in Materials and Manufacturing Engineering

|

2011

|

tom Vol. 49, nr 1

82--89

EN

Purpose: The core of the work consists in the elaboration of composite materials of aluminium alloy matrix, manufactured with the use of powder metallurgy technologies, including mechanical milling and hot extrusion and in determining the influence of the share of halloysite nanotubes - as the reinforcing phase on the structure and mechanical properties of fabricated composites. Design/methodology/approach: Mechanical milling and hot extrusion are considering as a method for fabricating composite metal powders with a controlled fine microstructure. It is possible by the repeated fracturing and re-welding of powders particles mixture in a highly energetic ball mill. Findings: It has been confirmed that halloysite nanotubes can be applied as a effective reinforcement in the aluminium matrix composites. High energy ball milling as a method of mechanical milling improves the distribution of the halloysite reinforcing particles throughout the aluminium matrix, simultaneously reducing the size of particles. Research limitations/implications: Contributes to research on structure and properties of aluminium alloy matrix composite material reinforced with mineral nanoparticles. Practical implications: The apparent density changes versus milling time can be used to control the composite powders production by mechanical milling and the presence of halloysite reinforcements particles accelerates the mechanical milling process. Conducted research shows that applied technology of composite materials production allows to obtain very good microstructural characteristics. Originality/value: The application of halloysite nanotubes as the reinforcing phase of metal composite materials is a novel assumption of the discussed work and an interesting challenge whereof realization would enable to use this mineral clay in an innovative and cost effective way.

15

Microstructure and mechanical properties of the annealed 6060 aluminium alloy processed by ECAP method

51%

Karoń M. , Kopyść A. , Adamiak M. , Konieczny J.

|

tom Vol. 80, nr 1

31--36

EN

Purpose: The main goal of this paper is to present the investigation results of microstructural evolution and mechanical properties changes in commercial EN AW 6060) aluminium alloy after intensive plastic deformation, obtained by equal channel angular pressing (ECAP) techniques in an annealed state. Design/methodology/approach: Annealing heat treatment was used to remove various types of internal stress in a commercially available alloy in order to increase workability of the material. The evolution of its properties and material behaviour was evaluated after 2,4,6,and 8 passes of the ECAP process. Findings: It was found that the mechanical properties and microstructure during intensive plastic deformation, such as that during the ECAP process, were changed. Plastic deformation refined grains in the aluminium alloy and increased its mechanical properties. Research limitations/implications: The presented study shows results of the investigated material in an annealed state. Practical implications: The applied processing route allows development of materials characterized by high strength and ultrafine grain microstructure compared to un-deformed annealed aluminium alloy. Originality/value: The work presents data about the influence of intensive plastic deformation on the microstructure and mechanical properties of 6060 aluminium alloy after annealing.

16

Neuroprotective potential of biphalin, mulitireceptor opioid peptide, against excitotoxic injury in vitro

51%

Adamiak M. , Kowalczyk J. , Lipkowski A. , Zablocka B.

|

tom 69

|

nr 3

EN

Biphalin is a dimeric opioid peptide, that exhibits a high affi nity for all three opioid receptors types (miu, delta and kappa). When administered intracerebroventricularly it has been shown to be more potent than morphine and ethorphine at eliciting antinociception. Biphalin is currently undergoing intensive preclinical study. It is recognized in recent years that activation of delta-opioid receptor elicits neuroprotection against hypoxia and ischemia, but the underlying mechanisms are not fully understood. In this study we tested the effect of biphalin and the inhibition of opioid receptors by naltrexon (Ntx) on survival of neurons in rat organotypic hippocampal culture challenged with NMDA in vitro. Cell survival was estimated with fl uorescent cell-death marker propidium iodide. Our main fi ndings are that (1) biphalin in the concentration of 100 μM reduces NMDA-induced neuronal damage; (2) biphalin neuroprotective effect is abolished by opioid receptors antagonist naltrexon; (3) naltrexon by itself does not change NMDA-induced neuronal damage; (4) reduced number of dead cells was clearly shown even when biphalin was applied with a delay after NMDA challenge. These results demonstrate that biphalin, multireceptor opioid peptide, can reduce NMDA-induced neuronal damage. This work was supported by MSHE Polish Mitochondrial Network grant.

17

Comparison of the PVD coatings deposited onto hot work tool steel and brass substrates

51%

Polok-Rubiniec M. , Lukaszkowicz K. , Dobrzański L. A. , Adamiak M.

|

tom Vol. 24, nr 2

195-198

EN

Purpose: The aim of the research is the investigation of the structure and mechanical properties of monolayers CrN, TiN and multilayers TiN/TiAIN and Ti/TiAIN coatings deposited by PVD techniques onto the substrate from the X37CrMoV5-1 steel and CuZn40Pb2 brass. Design/methodology/approach: The microhardness tests were made on the dynamic ultra-microhardness tester. Tests of the coatings' adhesion to the substrate material were made using the scratch test. The wear and friction tests were performed on a standard pin-on-disc device. Findings: The monolayer PVD coatings deposited onto hot work steel and brass substrate demonstrate the high hardness, adhesion and wear resistance. The critical load LC2, which is in the range 32-60 N, depends on the coating and substrate type. The friction coefficient for the investigated coatings is within the range of 0.33-0.75. Practical implications: The investigation results will provide useful information to applying the PVD coating for the improvement of mechanical properties of the hot work tool steels and brass substrates. Originality/value: It should be stressed that the mechanical properties of the PVD coatings obtained in this work are very encouraging and therefore their application for products manufactured at mass scale is possible in all cases where reliable, very hard and abrasion resistant coatings, deposited onto tools steel and brass substrate are needed.

18

Composite materials based on EN AW-Al Cu4Mg1(A) aluminum alloy reinforced with the BN ceramic particles

51%

Włodarczyk-Fligier A. , Adamiak M. , Dobrzański L. A.

|

tom Vol. 42, nr 1

29-36

EN

Purpose: the aim of the project was to evaluate of the effect of heat treatment and the reinforcing BN particles content on the mechanical properties, abrasive wear and corrosion resistance in the NaCl water solution environment on the EN AW-AlCu4Mg1(A) aluminium alloy matrix composite. Design/methodology/approach: Some of the composite materials were hyperquenched for 0.5 h at the temperature of 495°C with the subsequent cooling in water, and were quench aged next for 6 h at 200°C. Hardness tests were made on HAUSER hardness tester with the Vickers method at 10 N. Static compression and tensile tests of the fabricated composite materials were made on the ZWICK 100 type testing machine at room temperature. Abrasion resistance wear tests were carried out with the constant number of cycles of 5000 (120 m) at various loads: 4, 5, 6, 7, and 8 N. Test pieces were rinsed in the ultrasonic washer to clean them and next were weighed on the analytical balance with the accuracy of 0.0001 g to check the mass loss. Corrosion tests were made in 5% water NaCl solution. Findings: Besides visible improvement of mechanical properties: hardness, compression strength and tensile strength, wear resistance there were also observed the influence of heat treatment on the corrosion resistance of composite materials in 3% NaCl solution. Practical implications: Tested composite materials can be applicate among the others in automotive industry but it requires additional researches. Originality/value: It was demonstrated that the mechanical properties, as well as the wear and corrosion resistance of the extruded composite materials with the EN AW-Al Cu4Mg1(A) alloy matrix may be formed by the dispersion hardening with the BN particles in various portions and by the precipitation hardening of the matrix.

19

Wpływ obróbki cieplnej na odporność korozyjną materiałów kompozytowych o osnowie EN AW-2124 wzmacnianych cząstkami ceramicznymi Al2O3

51%

Dobrzański L. A. , Włodarczyk A. , Adamiak M. , Nawrat G.

Kompozyty

|

2005

|

tom R. 5, nr 1

30-34

PL

Przedstawiono wyniki badań wpływu obróbki cieplnej na odporność korozyjną materiałów kompozytowych aluminium--cząstki ceramiczne. Badaniom poddano materiały kompozytowe o osnowie aluminiowej EN AW-2124 wzmacniane cząstkami ceramicznymi Al2O3 o różnym udziale objętościowym. Badane materiały poddane były obróbce cieplnej w celu polepszenia ich odporności korozyjnej. Te same rodzaje materiałów kompozytowych badane były bez obróbki, co umożliwiło porównanie odporności korozyjnej materiałów w obu stanach. Analizowane wyniki badań korozyjnych, określonych metodą potencjo-dynamiczną w 3% roztworze wodnym NaCl, wskazują, że podatność korozyjna badanych materiałów kompozytowych zależy od udziału objętościowego cząstek wzmacniających, a także od stanu, w jakim były badane. Na podstawie wyznaczonych krzywych polaryzacji anodowych stwierdzono, że badane materiały są podatne na korozję wżerową. Przedstawione wyniki badań wskazują, że materiały kompozytowe wzmocnione cząstkami ceramicznymi przy udziale 5 i 10% charakteryzują się większą odpornością korozyjną w wybranym środowisku w porównaniu do materiału osnowy, natomiast przy udziale 15% odporność ta jest gorsza, zwiększa się prąd roztwarzania anodowego i maleje opór polaryzacji. Porównanie otrzymanych wyników korozyjnych w obu stanach pozwala na stwierdzenie, iż przeprowadzona obróbka cieplna wpływa na polepszenie odporności korozyjnej materiałów kompozytowych.

EN

Investigation results are presented of the heat treatment effect on the corrosion resistance of the aluminium-ceramic particles composites. Examinations were made of the EN AW-2124 aluminium alloy (Table 1), and also of the composite materials with the matrix from this aluminium alloy reinforced with the Al2O3 ceramic particles with varying volume fractions. The X-ray phase analysis of the composite materials made it possible to identify reflections coming from the aluminium matrix and of the reinforcing particles (Fig. 1). The metallographic examinations of the investigated composite materials made it possible to observe the homogeneous distribution of the reinforcing material in the matrix; however, banding of the reinforcing particles parallel to the extrusion direction was noted on the longitudinal microsections (Fig. 2). Examinations of the composite materials on the scanning electron microscope before their heat treatment made it possible to reveal occurrences of the Al-Cu-Mg-Mn intermetallic phases precipitations (Fig. 3). The investigated materials were subjected to heat treatment to improve their corrosion resistance. The same types of the composite materials were also examined without the heat treatment, which made it possible to compare their corrosion resistance in both states. The analysed results of the corrosion tests, determined using the potentiodynamic method in the 3% water solution of NaCl indicate that the corrosion susceptibility of the investigated composite materials depends on the volume fraction of the reinforcing particles and also on the state in which they were examined. It was found out, basing on the determined anode polarisation curves and also on the electrochemical parameters (Table 2) that the investigated materials are susceptible to pitting corrosion. The investigation results indicate that the composite materials reinforced with the ceramic particles with the portions of 5 and 10% are characteristic of a higher corrosion resistance in the selected environment, compared to the matrix material, whereas at the 15% portion this resistance is worse, the anode digestion current grows and the anode polarisation resistance decreases. Comparison of the corrosion test results in both states makes it possible to state that the heat treatment improves the corrosion resistance of the composite materials. The exemplary microphotographs of the examined specimens' surfaces after the corrosion tests (Fig. 5) confirm the analysed investigation results.

20

Analiza struktury i składu chemicznego połączeń spawanych: płyta trudnościeralna - stal konstrukcyjna

51%

Górka J. , Adamiak M. , Darda E.

Przegląd Spawalnictwa

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2011

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tom R. 83, nr 7

31-35

PL

W artykule przedstawiono analizę strukturalną i składu chemicznego połączenia spawanego płyty trudnościeralnej ze stalą konstrukcyjną S235JR wykonanego metodą MAG drutem litym G3Si1 o średnicy 1,2 mm w osłonie mieszanki aktywnej Arcal 21 (92% Ar + 8% CO2). Przeprowadzone badania wizualne i penetracyjne, badania metalograficzne: makro- i mikroskopowe oraz mikroanaliza rentgenowska składu chemicznego i rozkładu pierwiastków stopowych w obszarze spoiny pozwoliły na określenie zmian struktury i towarzyszących im zmian składu chemicznego zachodzących w poszczególnych obszarach złącza spawanego. Badania dowiodły, że w wyniku spawania dochodzi do stopienia materiału warstwy odpornej na zużycie ścierne i przejścia węglików do spoiny oraz częściowego niejednorodnego wymieszania spawanych materiałów, co powoduje wzrost twardości w tym obszarze do 600 HV i może być przyczyną powstania pęknięć od strony lica spoiny. Badania nie wykazały obecności pęknięć w obszarze grani spoiny. Analizując wyniki badań, należy stwierdzić, że wykonane złącze spawane spełnia wymogi eksploatacyjne stawiane połączeniom tego typu.

EN

The article analyzes the structural and chemical composition of the abrasive-resistant plates with structural steel S235JR welded joints made by MAG G3Si1 solid wire with a diameter of 1.2 mm in the shielding active gas Arcal 21 (92% Ar + 8% CO2). Visual and penetrant testing, metallographic examination: macro, micro and microscopic X-ray analysis of chemical composition and distribution of alloying elements in the weld area allowed us to identify structural changes and accompanying changes in chemical composition occurring in the various areas of the welded joints. Research shown that the abrasive-resistant layer is melted in the welding process. Moreover the carbide transition into the weld and the partial non-homogenous mixing of welded materials, which increases the hardness in this area up to 600 HV and may cause cracks on the face of the weld are obtained. The study does not reveal the cracks in the weld root. Analyzing the results of the study should be noted that the welded joint made meets the requirements of this type of connections.