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1

Powłoki użytkowe na narzędziach i częściach maszyn dla przemysłu metali nieżelaznych

100%

Richert M. W. , Zawadzka M.

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tom T. 25, nr 1

5--26

PL

W artykule przedstawiono przegląd literaturowy oraz badania własne dotyczące powłok ochronnych stosowanych na narzędziach i częściach maszyn dla przemysłu metali nieżelaznych. Pokazano, że dobór odpowiedniej metody wytwarzania jak i składu chemicznego powłoki pozwala w znacznym stopniu zwiększyć trwałość pokrywanego elementu. Omówiono także wpływ parametrów procesu osadzania na jakość wytwarzanych powłok.

EN

In the paper the review of literature and own investigations concerning the protective coatings deposited at tools and parts of equipment using in the non-ferrous metals industry have been presented. It has been shown that choice of proper method of production and also the chemical composition of coating allowing in large step increase the durability of the deposited element. The influence of process deposition parameters on the quality of coatings was also discussed.

2

The deposition of WC-Co coatings by EBPVD technique

80%

Richert M. W. , Mazurkiewicz A. , Smolik J. A.

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tom Vol. 57, iss. 2

511-515

EN

The WC-Co carbides are widely used to deposit protective coatings on engineering surfaces against abrasion, erosion and other forms of wear existence. The nanostructure coatings offer high strength, a low friction coefficient and chemical and thermal stability. WCo coatings were deposited using EBPVD technique realized in original technological process implemented in the hybrid multisource device, produced in the Institute for Sustainable Technologies - National Research Institute in Radom (Poland). The different kind of precursor sources was used. Depending on the source of precursors nanostructure of coatings forms continuous film or consist from nano-carbides. Nanocrystalline WC-Co coatings show hardness in the range of 510-1266 HV. The microstructure of coatings were observed by transmission electron microscopy (TEM). The phase consistence were determined byBrucker D8 Discover-Advance Diffractometer. The paper presents the original technological equipment, methodology, and technological parameters for the creation of the nanocomposite coatings WC.

PL

Węgliki WC-Co są szeroko używane do osadzania na powierzchniach inżynierskich jako ochrona przeciwko tarciu, erozji i innym formom zużycia. Powłoki nanostrukturalne wykazują wysoka wytrzymałość, niski współczynnik tarcia oraz chemiczną i termiczną stabiność. Powłoki WC-Co zostały osadzane techniką EBPVD przy użyciu oryginalnego technologicznego procesu z hybrydowym źródłem prekursorów, w Instytucie Technologii Eksploatacji w Radomiu (Polska). Użyto różnego rodzaju źródeł prekursorów. W zależności od rodzaju użytego źródła prekursorów nanostrukturalne powłoki były zbudowane z ciągłych warstw lub z nano-weglików. Mikrotwardość nanokrystalicznych powłok mieściła się w zakresie 510-1266 μHV. Mikrostruktura powłok była obserwowana transmisyjnym mikroskopem elektronowym (TEM). Skład fazowy powłok określono za pomocą aparatu rentgenowskiego Brucker D8 Discover-Advance Diffractometer. Artykuł prezentuje oryginalne technologiczne urządzenie, metodologię i technologiczne parametry pozwalające na wytworzenie nanokompozytowej powłoki WC.

3

Effect Of Severe Plastic Deformation On Microstructure Evolution Of Pure Aluminium

80%

Leszczyńska-Madej B. , Richert M. W. , Perek-Nowak M.

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2015

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tom Vol. 60, iss. 2B

1437--1440

EN

Processes of severe plastic deformation (SPD) are defined as a group of metalworking techniques in which a very large plastic strain is imposed on a bulk material in order to make an ultra-fine grained metal. The present study attempts to apply Equal-Channel Angular Pressing (ECAP), Hydrostatic Extrusion (HE) and combination of ECAP and HE to 99.5% pure aluminium. ECAP process was realized at room temperature for 16 passes through route Bc using a die having an angle of 90°. Hydrostatic extrusion process was performed with cumulative strain of 2.68 to attain finally wire diameter of d = 3 mm. The microstructure of the samples was investigated by means of transmission and scanning electron microscopy. Additionally, the microhardness was measured and statistical analysis of the grains and subgrains was performed. Based on Kikuchi diffraction patterns misorientation was determined. The measured grain/subgrain size show, that regardless the mode of deformation process (ECAP, HE or combination of ECAP and HE processes), grain size is maintained at a similar level – equal to d = 0.55-0.59 μm. A combination of ECAP and HE has achieved better properties than either single process and show to be a promising procedure for manufacturing bulk UFG aluminium.

4

The Microstructure and Properties of Hydrostatically Extruded Polycrystalline Aluminium Al99.5 / Mikrostruktura I Własności Wyciskanego Hydrostatycznie Polikrystalicznego Aluminium Al99.5

80%

Leszczyńska-Madej B. , Richert M. W. , Pachla W. , Skiba J.

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5

Microstructure characterization of chromium carbides coatings deposited by thermal spraying processes

61%

Richert M. W. , Książek M. , Pałka P. , Wawrzyniak S. , Grzelka R. , Płońska-Niżnik K.

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2012

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tom Vol. 55, nr 1

108--112

EN

Purpose: The Cr3C2-NiCr coatings were deposited by plasma spraying (PS) and high velocity oxy-fuel (HVOF) processes. The objective of the work concerns characterization of microstructure of sprayed coatings. In the investigated samples, apart from Cr3C2 carbide particles, the carbides Cr7C3 were also present according to the reported through X-ray diffraction analyses. It is likely that Cr7C3 carbides were formed thorough decarburization of Cr3C2. The microstructure of the thermal sprayed Cr3C2-NiCr coatings was characterized by optical (MO), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The fine-grained and nano-crystalline microstructure was found in the investigated coatings. The microhardness of coatings was measured. It was found that the coatings deposited in HVOF process have higher microhardnes than the plasma spraying one. The formation of chromium carbide phases in the coatings was discussed based on the microstructure observation results. Design/methodology/approach: The investigations of coating microstructure by optical microscopy (MO) Olympus GX51, scanning electron microscopy STEREOSCAN 420 and transmission electron microscopy JEM2010 ARP (TEM) were performed. The examination of phase consistence was determined by Brucker D8 Discover - Advance diffractometer with copper tubing. The microhardness of coatings was measured by Vickers method. Findings: The microstructures of Cr3C2-NiCr coatings were observed and analyzed. On the base of the microstructure investigations and contend of the chromium carbides the mechanism of thermal sprayed coating formation was discussed. Practical implications: The performed investigations contribute to the improvement of microstructure and properties of thermal spraying coatings used in the industrial applications. Originality/value: It was assumed that thermal spraying processes are able to form nano-crystalline microstructure of the chromium carbide coatings.

6

Processing of Copper by Hydrostatic Extrusion – Studies of Microstructure and Properties

51%

Leszczyńska-Madej B. , Richert M. W. , Nejman I. , Zawadzka P.

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nr 3