Wyniki wyszukiwania - Biblioteka Nauki

1

Właściwości warstw ochronnych nanoszonych metodą galwanizacji na styki łączników aparatowych

100%

Kolasik M.

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2010

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tom R. 48, nr 7

126-129

PL

W artykule przedstawiono wyniki badań przeprowadzonych z wykorzystaniem łączników aparatowych, na styki których naniesiono warstwę ochronną z niklu, złota i srebra. Sformułowano odpowiednie wnioski praktyczne dotyczące nanoszenia warstw ochronnych na styki łączników.

EN

The article features the results of tests conducted with the use of apparatus connectors on whose contacts a protective nickel-gold-silver layer was applied. Suitable practical conclusions were formulated with respect to the application of protective layers on the contacts of apparatus connectors.

2

Metoda wyznaczania przyrostu masy w procesie elektropolerowania

100%

Białostocka A. M. , Łukjaniuk A.

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tom Z. 16

115-121

PL

W artykule przedstawiono metodę wyznaczania przyrostu masy miedzi podczas procesu galwanicznego pokrycia przedmiotów. W metodzie tej (pozwalającej na kontrolę przyrostu masy miedzi bez przerywania procesu galwanizacji) wykorzystuje się prawo Faraday'a - m=klt. Czas trwania procesu galwanizacji oraz wartość prądu mierzona jest przy pomocy uniwersalnego miernika elektrochemicznego EMU. Autorzy przeprowadzili analizę błędu wyznaczania masy przedstawioną metodą.

EN

In the article was presented the appoint method of the copper mass increasing during the galvanotechnic process of the objects. In the introducing method (gives the opportunity to control the mass increasing without the galvanotechnic process interrupting) were used the Faraday's law - m=klt. The duration time of the galvanotechnic process and value of the current tension were measured by the universal electrochemical tool EMU. The authors carried out the analysis of the error of the copper mass appoint the introducing method.

3

Zinc exposure for female workers in a galvanizing plant in Northern Italy

75%

Riccò M. , Cattani S. , Signorelli C.

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nr 1

113-124

EN

Objectives: Very little is known regarding the toxicokinetics of inhaled zinc, in particular in the case of female workers and for modern, low exposure settings. Our aim is to evaluate the relationship of external zinc levels to those of serum and urine for female workers. Material and Methods: Eleven female workers (age: 41.7±8 years old, body mass index (BMI): 23.5±4.2 kg/m2) in a galvanizing plant were investigated. Exposure assessment consisted of personal/environmental air samples, and measurement of zinc in serum (collected at the end of first shift of the working week (T1)) and urine, collected before the first shift of the working week (T0), T1 and at the end of the last shift of the working week (T2). Results: Both environmental and personal air samplings for zinc and zinc compounds were below the recommended by the German Research Foundation (Deutsche Forschungsgemeinschaft – DFG) limit values of 2 mg/m3 (7.34±2.8 μg/m3 and 8.31±2.4 μg/ m3, respectively). Serum (118.6±20.9 μg /dl) and urine zinc levels were within reference values for female Italian subjects: the latter increased from 56.4±33.5 μg/dl at T0, to 59.8±37.0 μg/dl at T1, and ultimately 65.4±34.4 μg/dl at T2, but no significant trend was found. End of shift (Spearman’s correlation coefficient p value = 0.027) and differential excretion of urinary zinc (both: T0 vs. T1 and T0 vs. T2) were correlated with airborne zinc concentration (p = 0.002 and 0.006, respectively). Conclusions: In general, our data suggests that urine may be a useful medium also for female in order to assess zinc exposure. Further studies are required in order to evaluate whether differential excretion may be useful for the biomonitoring of zinc exposure in the workplaces also for male workers. Int J Occup Med Environ Health 2018;31(1):113–124

4

Effect of diffusion on platinum coatings deposited on the surface of nickel based superalloy by the electroplating process

75%

Yavorska M. , Sieniawski J.

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2010

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tom Vol. 45, nr 1

56-60

EN

Purpose: In this paper the effect of diffusion on platinum coatings deposited on the surface of nickel based superalloy was evaluated. Design/methodology/approach: The platinum coatings with thickness of 3 mm and 7 mm were deposited by electroplating process on Inconel 713 LC Ni-base superalloy. The heat treatment of electroplating coatings at the temperature 1050 °C during 2h under argon atmosphere was performed. The microstructure investigations of the heat treated coatings were conducted by the use of optical microscope (Nikon Epiphot 300) and a scanning electron microscope (Hitachi S-3400N) equipped with an X-radiation detector EDS (VOYAGER of NORAN INSTRUMENTS). The phase composition was identified by X-ray (ARL X'TRAX) diffractometer. The surface roughness parameter - Ra was evaluated by Perthometer S2 MAHR equipment. Findings: The microstructure of platinum electroplating coating with thickness of 3 Μm after diffusion treatment consists of two phases: γ-Ni and (Al0.25Pt0.75)Ni3. The increase of platinum thickness from 3 Μm to 7 Μm does not influence the phase composition of heat treated coatings. Heat treatment of platinum electroplating coatings causes the increase of surface roughness parameter as a result of unequal mass flow of platinum and nickel. Research limitations/implications: The results will be used in the future investigations to explain the mechanism of reaction of platinum as a modifier in aluminide coatings. Practical implications: The platinum electroplating coatings after diffusion treatment and aluminizing process are widely used as coatings for turbine blades of aircraft engines. Originality/value: The paper includes the results of microstructure and surface roughness investigations of platinum electroplating coatings with 3 mm and 7 Μm thickness after diffusion treatment.

5

Weldability of 440 MPa galvanized steel with inverter DC resistance spot welding process

63%

Hwang I. , Yoon H. , Kang M. , Kim D.

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tom Vol. 42, nr 1

37-44

EN

Purpose: This paper comparatively analyzes resistance spot weldability depending on whether or not 440 MPa-grade steel is galvanized at inverter DC spot welding. Design/methodology/approach: To compare the resistance spot weldability depending on whether or not the steel is galvanized, an inverter DC welding system was designed. Then, using this system, both tensile strength testing and macro-section testing were conducted on SPRC440 (uncoated steel) and SGARC440 (galvanized steel), and weldability was evaluated. Suitable welding conditions were calculated using the resistance spot welding variables such as electrode force, welding time and lobe diagram on the welding current. The low limit of the lobe diagram was set to the low limit of the tensile strength of 440 MPa-grade steel while the high limit was set depending on whether or not expulsion was detected. Findings: Compared to uncoated steel, galvanized steel had lower suitable welding current conditions and a narrower lobe diagram. Research limitations/implications: This paper compared resistance spot weldability and lobe diagram depending on whether or not 440 MPa-grade steel is galvanized. Practical implications: This paper confirms the weldability of galvanized steel by comparing resistance spot weldability depending on whether or not steel is galvanized. Originality/value: For analysis of resistance spot weldability depending on whether or not steel is galvanized, weldability was compared between SPRC440 (uncoated steel) and SGARC440 (galvanized steel) under the same welding conditions. As a result, compared to uncoated steel, galvanized steel had lower suitable welding current conditions and a narrower lobe diagram.