Ocjena djelotvornosti zaštitnih premaza na ručno očišćenim metalnim površinama u uvjetima visoke korozivnosti

undergraduate thesis

• Title (english): Assessment of protective coating efficiency on hand-cleaned metallic surfaces in highly corrosive environments
• Author: Marko Matulić
• Mentor: Sanja Martinez (mentor)
• Committee member: Sanja Martinez (predsjednik povjerenstva)
• Committee member: Helena Otmačić Ćurković (član povjerenstva)
• Committee member: Igor Sutlović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2015-09-17, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences; Materials

Abstract

U modernoj industrijskoj infrastrukturi današnjice korozija predstavlja jedan od
najvećih i najzanimljivijih problema. Brojna znanstvena istraživanja stavljaju poseban
naglasak na antikorozivnu zaštitu, a sve s ciljem povećanja učinkovitosti,
ekonomičnosti i sigurnosti industrijskih procesa. U teorijskom dijelu ovog završnog
rada detaljno su opisani razni oblici korozije, te je objašnjena učinkovitost zaštite metala
od korozije primjenom premaza.
U eksperimentalnom dijelu su vršena laboratorijska ispitivanja na zahrđalim i
pjeskarenim pločicama izrezanim s jako zahrđalog industrijskog objekta. Uzorci su
temeljito ručno očišćeni te je u hrđi uklonjenoj s površine izmjerena koncentracija
kloridnih iona. Zahrđale i pjeskarene ploče tretirane su pretvaračima hrđe na osnovi
fosfatne kiseline i tanina. Na ukupno 12 ploča, s različitim kombinacijama podloge i
pripreme površine, nanesen je temeljni dvokomponentni epoksidni premaz debljine 50
μm te dva sloja pokrivnog premaza istog tipa i debljine 125 μm + 125 μm. Obzirom da
je specifičnost jako zahrđalih uzoraka nejednolika debljina i nepravilna površina,
mjereni su hrapavost površine pjeskarenog i zahrđalog uzorka te debljina premaza na
zahrđaloj pločici. Po jedan od dva identična uzorka izložen je zraku sa 100% vlažnosti
pri 30 °C u periodu od 720 sati. Na uzorcima je na kraju eksperimenta mjerena
prionjivost premaza.
Rezultati su pokazali važnost pripreme površne jako zahrđalih objekata
pjeskarenjem kao jedinog rješenja za njihovu uspješnu zaštitu od korozije premazima.

Abstract (english)

In modern industrial infrastructure nowadays, corrosion is depicted as one of its
greatest and most interesting problems. Numerous scientific research highlights
anticorrosive protection, aiming towards increased effectiveness, economy and safety of
industrial processes. Theoretical section of this paper contains description of various
forms of corrosion. Also, metal protection by protective coatings been explained.
Experimental section contains descriptions of laboratory tests conducted on
rusted and sandblasted plates which were previously cut from a heavily rusted industrial
object. Samples were manually cleaned and concentration of chloride ions has been
measured in the surface-removed rust. Rusted and sandblasted plates were treated by
phosphoric acid and tannin based rust converters. On a total of 6 pairs of plates, each
pair having different combination of base and surface preparation, 50 μm thick epoxy
primer has been applied, along with two layers of top coat of the same type and 125 μm
+ 125 μm in thickness. Considering that rusted samples are specific for their uneven
thickness and irregular surface, surface roughness of sandblasted and rusted samples has
been measured. One of the two identical samples has been exposed to a 100 % humidity
and 30 °C atmosphere during 720 hours. Coating adhesion has been measured at the end
of the experiment by the pull-off test.
Results have indicated the importance of sandblasting of heavily rusted objects
as the only successful solution for their anticorrosive protection by protective coatings.

• Keywords: korozija; zaštitni premaz; prionjivost premaza
• Keywords (english): corrosion; protective coating; coating adhesion
• Language: croatian
• URN:NBN: urn:nbn:hr:149:547668
• Study programme: Title: Chemical Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2016-11-28 16:29:10