Proučavanje primjenjivosti in situ elektrokemijskog ispitivanja na patiniranim broncama

master's thesis

• Title (english): Studying the applicability of the in situ electrochemical testing on bronze patinas
• Author: Magdalena Eškinja
• Mentor: Sanja Martinez (mentor)
• Committee member: Sanja Martinez (predsjednik povjerenstva)
• Committee member: Helena Otmačić Ćurković (član povjerenstva)
• Committee member: Lidija Furač (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Za dobivanje podataka o stanju metalnog materijala in situ mogu se koristiti razne elektrokemijske tehnike. Elektrokemijska impedancijska spektroskopija (EIS) pokazala se posebno prikladnom metodom za in situ primjenu na kulturnom dobru. Ova studija istražuje primjenjivost ćelije s elektrolitskom pastom za EIS ispitivanje nepatiniranog bakra i bronce te patinirane bronce bez zaštitnog premaza i sa zaštitnim premazom. Usporedna mjerenja izvršena su u dvoelektrodnom i troelektrodnom sustavu s tri različite vrste elektrolita, vodenom otopinom natrijevog klorida, vodovodnom vodom i elektrolitskom pastom. Cilj ovog rada bio je usporediti mjerenja u dva prethodno navedena sustava elektrokemijskih ćelija, procijeniti ponovljivost mjerenja i utvrditi utjecaj različitih elektrolita. Izmjereni su EIS spektri te su numeričke vrijednosti impedancije pri 0,1 Hz uzete kao pokazatelj stupnja površinske zaštite patinom ili premazom. Izračunate vrijednosti relativne standardne devijacije ponovljivosti pokazale su zadovoljavajuće rezultate u slučaju elektrolitske paste i vodovodne vode. Usporedbom impedancije za različite elektrolite, utvrđeno je da mjerenja u vodenoj otopini natrijevog klorida nisu dala iskustveno utvrđeni raspored stupnja površinske zaštite. Elektrolitska pasta pokazala se kao perspektivan kandidat za mjerenje na licu mjesta ispravnim rangiranjem stupnja zaštite kroz impedanciju sljedećim redoslijedom: bakar> bronca> patinirana bronca> patinirana bronca sa zaštitnim premazom.

Abstract (english)

Various electrochemical techniques can be used to obtain information about the condition of a metallic material in situ. In particular electrochemical impedance spectroscopy (EIS) has been shown to be a suitable method for in situ measurements on cultural heritage. This study investigates the applicability of the paste electrolyte cell for EIS testing of non-patinated copper and bronze and patinated bronze without and with the protective coating. Comparative measurements were made with three-electrode and two-electrode electrochemical cells and in three different types of electrolytes, an aqueous solution of sodium chloride, tap water and electrolyte paste in the solid state. The aim of this work was to compare the measurements in the two previously mentioned types of electrochemical cells, to evaluate the repeatability of the measurements and to determine the influence of the different electrolytes. The EIS spectra were measured and the numerical values of impedance at 0.1 Hz were taken as an indicator of the level of surface protection by patina or coating. The calculated values of relative standard deviation of repeatability showed satisfactory results in the case of electrolytic paste and tap water. By comparing the impedance for different electrolytes, it was found that the aqueous solution of sodium chloride did not give a commonly observed rating of the degree of surface protection. Electrolyte paste in the solid state proved to be a promising candidate for in situ measurements by detecting the impedance ranking in the following order: copper> bronze> patinated bronze> patinated bronze with a protective coating.

• Keywords: in situ ispitivanje; korozija; elektrokemijska impedancijska spektroskopija
• Keywords (english): in situ measurements; corrosion; electrochemical impedance spectroscopy
• Language: croatian
• URN:NBN: urn:nbn:hr:149:838705
• Project: Number: IP-2019-04-5030; Title: Razvoj novih rješenja za karakterizaciju i zaštitu brončane kulturne baštine izložene vanjskom okolišu; Title: Development of New Solutions for Characterization and Protection of Bronze Cultural Heritage Exposed to Outdoor Environment; Acronym: BroCH; Leader: Helena Otmačić Ćurković; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Chemical Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-04-07 09:16:18