Wyniki wyszukiwania - BazTech

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Laser Cladding of WC/T-800 Cermet: Fabrication, Microstructure and Wear Properties

Kim Kyoung-Wook, Kim Young-Kyun, Park Sun-Hong, Lee Kee-Ahn

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 3

713--717

EN

This study fabricated a WC/T-800 cermet coating layer with Co-Mo-Cr (T-800) powder and WC powder using laser cladding, and analyzed its microstructure, hardness and wear properties. For comparison, casted bulk T-800 was used. Laser cladded WC/T-800 cermet coating layer showed circular WC phases in the Co matrix, and dendritic laves phases. The average laves phase size in the cermet coating layer and bulk T-800 measured as 7.9 µm and 60.6 µm, respectively, indicating that the cermet coating layer had a relatively finer laves phase. Upon conducting a wear test, the cermet coating layer added with WC showed better wear resistance. In the case of laser cladded WC/T-800 cermet coating layer, abrasion wear was observed; on the contrary, the bulk T-800 showed pulled out laves phases. Based on the above findings, the WC/T-800 cermet coating layer using laser cladding and the relationship between its microstructure and wear behavior were discussed.

2

Physio-mechanical & wear performance of banana fiber/walnut powder based epoxy composites

Gairola Surya P., Tyagi Yogesh, Gangil Brijesh, Jha Kanishk

Acta Innovations

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2021

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no. 41

42--55

EN

The present environmental condition indicates the immediate need for sustainable materials containing mainly natural elements for composite fabrication. Encouragement of natural fibers in composite materials can significantly reduce the greenhouse effect and the high cost of manufacturing synthetic fiber-based polymer composites. Hence, this study aimed to investigate the physio-mechanical properties of banana fiber (BF) fiber - based epoxy (EP) composites filled with walnut shell powder (WNP). Fabrication was carried out by mixing and cold pressing with fixed BF proportion and varying percentages of WNP (0%, 5%, 10%, 15 wt. %). The results obtained in the study suggest the mechanical properties of the BF/EP composite were enhanced with the addition of WNP as a filler. This is because the WNP filler occupies the spaces in the composite, which bridge the gaps between the banana fibers and the epoxy matrix; also, the inclusion of walnut powder in the BF/EP composites greatly enhanced their wear resistance. The microstructural properties of the composites were examined by scanning electron microscopy (SEM).

3

Microstructural Characterization and Mechanical Behavior of Copper Matrix Composites Reinforced by B4C and Sea Shell Powder

Sankar M., Pradeep Devaneyan S., Peter Pushpanathan D., Myszka D.

Journal of Casting & Materials Engineering

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2018

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Vol. 2, no. 1

24--29

EN

This paper investigates the microstructural and mechanical properties of copper metal matrix composites reinforced with B4C and crushed sea shell particles (fabricated using powder metallurgy). In powder form, copper is widely used in structural applications. Copper also possesses very good electrical and thermal conductivity, ductility, and corrosion resistance. B4C is the third-hardest-known material that also possesses excellent toughness and wear resistance. Sea shells are readily available along coastal areas. Therefore, an attempt has been made in this work to investigate the feasibility of its utilization in powder metallurgy. Two batches of samples were prepared. In the first batch, the percentage of boron carbide and copper powder were varied, and seashell powder was not included. In the second batch, the percentages of B4C, copper, and sea shell powder were varied in order to assess the change effected by the sea shell material. The sintered samples of both batches were subjected to microstructural characterization to ascertain the homogeneous distribution of the reinforcements. The microhardness and wear resistance of all of the fabricated samples were assessed. The results confirmed that the inclusion of 2% sea shell powder (by weight) with 10% boron carbide improved the wear resistance and hardness of the composite.

4

Eksploatacja emulsyjnych cieczy chłodząco-smarujących w obróbce ściernej

Karaś J., Bochnia J., Stępień A.

Przegląd Mechaniczny

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2015

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nr 1

26--29

PL

W pracy omówiono zagadnienia związane z eksploatacją cieczy chtodząco-smarujących stosowanych w obróbce ściernej. Przedstawiono metody chłodzenia oraz wyniki eksperymentalnych badań emulsji stosowanej bezpośrednio w obrabiarce. Badania przeprowadzono pod kątem wpływu rozwoju bakterii na degradację cieczy chłodząco-smarującej. Wykazano, że mikroorganizmy mogą w istotny sposób pogarszać właściwości przeciwzużyciowe i antykorozyjne stosowanych emulsji chłodząco-smarujących.

EN

This paper deals with problems associated with exploitation of metalworking fluids used in the abrasive machining. The cooling methods were described with presentation of the results obtained during exploitation in the machine. The effect of microbial growth and its influence on guality of coolant was examined. After research it was found that microorganisms deteriorate antiwear and anticorrosion properties of used metalworking fluids.

5

Wear properties of hemp, ramie and linen fabrics after liquid ammonia/crosslinking treatment

Li J., Feng J., Zhang H., Zhang J.

Fibres & Textiles in Eastern Europe

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2010

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Vol. 18, no. 5 (82)

81--85

EN

Desized and scoured hemp, ramie and linen fabrics were treated with liquid ammonia over practical ranges, followed by crosslink finishing with modified DMDHEU (Clariant Chemical Co). Appearance qualities, as well as comfort and mechanical properties were measured to investigate the wear behavior of all-cellulosic fabrics. The crease recovery, washing shrinkage and other appearance qualities of cellulosic fabrics were improved by NH3 treatment and especially by liquid ammonia pretreatment in conjunction with crosslink finishing. The moisture regain of the cellulosic fibers was increased by NH3 treatment, but on the other hand, water retention was decreased. The air permeability, moisture permeability and other comfort properties of the cellulosic fabrics were decreased by crosslink finishing, whereas those of NH3/crosslinked fabrics were greater than untreated ones. As a pretreatment for crosslink finishing, liquid ammonia significantly improved the tensile strength retention and tear strength in cellulosic fabrics compared to crosslink finishing alone.

PL

Tkaniny z konopi, ramii oraz lnu po usunięciu klejonki i odtłuszczeniu obrabiano ciekłym amoniakiem i sieciowano DMDHEU (Clariant Chemical Co). W celu określenia zachowania podczas użytkowania tkanin z włókien celulozowych oceniano ich wygląd oraz właściwości mechaniczne. Obróbka NH3 i wstępne działanie ciekłym azotem w połączeniu z sieciowaniem poprawiły odporność tkaniny na gniecenie, kurczliwość po praniu oraz inne cechy wyglądu tkanin. Absorpcja włókien celulozowych wzrosła po obróbce NH3, ale z innej strony, spadła retencja wody. Po sieciowaniu pogorszyła się przepuszczalność powietrza i wilgoci, a także inne właściwości użytkowe tkanin, podczas gdy te same cechy tkanin obrabianych NH3 i sieciowanych były lepsze niż tkanin nie obrabianych. Poprzedzenie sieciowania obróbką ciekłym amoniakiem znacząco polepsza wytrzymałość w porównaniu do tkanin poddanych samemu sieciowaniu.