Mikrobiološki poticana korozija nehrđajućih čelika

undergraduate thesis

• Title (english): Microbiologically influenced corrosion of stainless steels
• Author: Luka Stefanović
• Mentor: Vinko Šimunović (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2020-09-24, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Nehrđajući čelici nalaze sve širu primjenu u različitim granama industrije kao što su kemijska, prehrambena, farmaceutska, građevinarstvo, brodogradnja te u medicini i svakodnevnom životu. Tako široka primjena nehrđajućih čelika najlakše se može objasniti zbog njihovih izuzetnih mehaničkih svojstava i visoke korozijske postojanosti. Ipak često se tijekom njihovog korištenja mogu dogoditi neočekivana oštećenja poput lokaliziranog oštećivanja rupičastom korozijom ili korozijom u procijepu. Ova oštećenja su najčešća na nehrđajućim čelicima koji se koriste u sustavima gospodarenja vodom. U takvim uvjetima bi nehrđajući čelici trebali biti otporni na korozijsko razaranje, ali do njega svejedno dolazi upravo zbog toga što su sustavi za gospodarenje vodom pogodni za razmnožavanje mikroorganizama koji svojim metaboličkim procesima mjenjaju korozivnost okoline i postepeno razaraju metale koji postaju neotporni na mehanizme korozije. U radu su opisani nehrđajući čelici, njihova podjela i svojstva. Također je opisana njihova primjena u industriji, poglavito primjena u sustavima gospodarenja vodom. Detaljnije je opisana i mikrobiološki poticana korozija te mehanizmi njenog nastajanja. Sagledane su i metode sprječavanja nastajanja mikrobiološki poticane korozije i izneseni su primjeri oštećenja koja se mogu pojaviti na nehrđajućim čelicima u sustavima gospodarenja vodom.

Abstract (english)

More and more applications of stainless steel are found in techonology and different branches of industry such as chemical, food and pharmaceutical industry, civil engineering, naval architecture, medicine and in every day lives. Their extraordinary mechanical properties as well as their high resistance to corrosion can easily provide an explanation for their wide usage. However, there are often unexpected localised damages of material that can occur in the form of pits as a consequence of pitting corrosion or crevice corrosion processes. These damages are more common on stainless steels that are used in water management systems. In such conditions, stainless steel should be completely resistant to types of localised corrosion mentioned above, but the damage still occurs because water management systems are extremely suitable for reproduction of microorganisms that change corrosivity of their surroundings with their metabolical processes and release chemical compunds that gradually devastate the metal which in turn becomes less resistant to other types of corrosion. Stainless steels, their classification and properties, application in industries (mainly in water management systems) are described in this bachelor thesis. Microbiologically influenced corrosion and its mechanisms are also described in detail. Methods of prevention of microbiologically influenced corrosion are percieved as well and examples of damage that can occur on stainless steel used in water management systems.

• Keywords: Nehrđajući čelici; mikrobiološki poticana korozija; sustavi gospodarenja vodom
• Keywords (english): Stainless steel; microbiologically influenced corrosion; water management systems
• Language: croatian
• URN:NBN: urn:nbn:hr:235:794390
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-09-24 16:15:06