Wyniki 1-3 spośród 3 dla zapytania: authorDesc:"Andrzej Przywóski"

Badania przydatności materiałów na retorty do niskotemperaturowego nawęglania stali austenitycznych DOI:10.15199/28.2015.4.6


  In the article the usefulness of H17, 0H18N9, H25N20S2 steel and 75Ni-25Cr alloy in use on furnace retorts designed for low-temperature carburizing of austenitic steels in synthetic or endothermic atmospheres was investigated. As evaluation criterion was considered ability of the material to catalyse gaseous reactions and soot deposition and the possibility of carburizing process conducting for austenitic steel 0H18N9. The studies were conducted in furnace with stationary retort closed with a furnace cover with a sand seal, as well as in portable retort installed in a separate furnace in the case of studies of suitability of retort made of 0H18N9 steel. In the case of a stationary retort made of 0H18N9 steel were studied: a) effect of endogas dilution with nitrogen or hydrogen on soot deposition in retort and Armco foil state after retort heating at temperature 440°C; small amounts of soot in retort and clean Armco foil were obtained in a mixture of 42% endogas with nitrogen or 33% endogas with hydrogen, b) effect of the retort oxidation at temperature 570°C on changes of dew point and soot deposition after heating of oxidized retort to temperature in the range 300÷470; in the case of endogas, dew point increased with increasing temperature and soot appeared in the oxidized zone above 400°C; dilution of endogas with hydrogen shifted the boundary of soot deposition to a higher temperature, c) effect of preliminary oxidation of Armco iron foil on ability for soot deposition on its surface; during heating in endogas at temperature 500°C for 4 hours it was found that soot appeared on the foils oxidized at temperature 450°C and 530°C, while heating in mixture of H2-N2 in endogas led to the appearance of soot only on foil oxidized at temperature 520°C; on the foils oxidized at temperature below 450°C or not-oxidized soot didn't occurred. In addition, attempts of heating and carburizing in portable retort made of 0H18N9 steel were conducted. Whe[...]

Otrzymywanie i właściwości korozyjne elektrolitycznych powłok Co-P


  W pracy przedstawiono wyniki badań dotyczących otrzymywania elektrolitycznych powłok stopowych Co-P w warunkach prądu stałego. Zbadano wpływ gęstości prądu osadzania na morfologię, powierzchniowy skład chemiczny oraz odporność korozyjną powłok. Badania wykazały, że wraz ze wzrostem gęstości prądu katodowego, zmniejsza się zawartość P w powłoce, a tym samym zmniejsza się odporność korozyjna elektrolitycznych powłok Co- P. Otrzymane wyniki porównano z odpornością korozyjną powłok Co i Cr. Słowa kluczowe: ochrona przed korozją, powłoka kobalt-fosfor, właściwości ochronne, badania elektrochemiczne The production and corrosion properties of electrolytic Co-P alloy coatings The results of studies on the formation of Co-P electrolytic alloy coatings under direct current are presented. The effect of cathodic current density on morphology, chemical composition and corrosion resistance of the coatings, is investigated. Protective properties are assessed by means of electrochemical measurements carried out in the sodium sulphate and sodium chloride solution. The increase in cathodic current density leads to a decrease of P in the coating, and diminishing of the protective properties of the coatings. The results are compared with corrosion resistance of Co and Cr coatings. Keywords: corrosion protection, cobalt-phosphorus coating, protective properties, electrochemical measurements ochrona przed korozja 7/2011 [...]

 Strona 1