magistrsko delo
Žan Blaž Slivnik (Avtor), Milan Bizjak (Mentor), Tadeja Kosec Mikić (Komentor)

Povzetek

Predmet te magistrske naloge je bilo povečanje koncentracije aluminija v površinski plasti jekel 16Mo3, 13CrMo4 5, 10CrMo9-10 in X2CrNi18 9 in pridobiti informacije o korozijski obstojnosti. Analiza konkretno obravnava osnovne materiale, tj. jekla v osnovnem stanju, in v aluminiziranem stanju, tj. jekla z aluminijem obogatene površinske plasti. Z namenom povečanja količine aluminija v površinski plasti smo jekla toplotno obdelali s postopkom aluminiziranja v zasipu. Aluminiziranje je potekalo le po plinski fazi pri trdni mešanici, ki sestavlja zasip. Uporabljeni zasip kot sredstvo za aluminiziranje je bila mešanica več vrst prahu, sestavljena iz 1 mas. % Al, 1 mas. % NH4Cl in 98 mas. % Al2O3. Postopek je potekal na 900 °C in času štirih ur v cevni peči. Po aluminiziranju smo pridobili informacije o razvoju mikrostrukture, izvedli meritve trdote in z elektrokemijskimi metodami določili korozijske lastnosti. Elektrokemijske lastnosti jekel so bile določene z meritvami linearne polarizacije, potenciodinamskih meritev in elektrokemične impedančne spektroskopije. Elektrokemijske metode preskušanja smo izvajali v 0,1 M raztopini NaCl pri sobni temperaturi. Na podlagi rezultatov preiskav smo proučili in analizirali vpliv aluminiziranja na obnašanje obravnavanih jekel s končnim ciljem ocenitve korozijskih lastnosti. Osnovni cilj raziskave je bil, da se na podlagi opravljenih elektrokemijskih meritev ovrednoti z aluminijem obogatena površina v smislu izboljšanja korozijske odpornosti. Jeklom se je z alumniziranjem povečala korozijska odpornost v 0,1 M NaCl. Pri nerjavnem jeklu X2CrNi18 9 se je z alumniziranjem korozijska odpornost zmanjšala v 0,1 M NaCl.

Ključne besede

Aluminiziranje v zasipu;difuzija;korozijska odpornost;potenciodinamskih meritev;elektrokemična impedančna spektroskopija;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.09 - Magistrsko delo
Organizacija: UL NTF - Naravoslovnotehniška fakulteta
Založnik: [Ž. B. Slivnik]
UDK: 669
COBISS: 32982275 Povezava se bo odprla v novem oknu
Št. ogledov: 451
Št. prenosov: 108
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: influence of aluminization on the corrosion properties of steels
Sekundarni povzetek: The subject of this master's thesis was an increase of the concentration of aluminum in the surface layer of steels 16Mo3, 13CrMo4 5, 10CrMo9-10 and X2CrNi18 9, and moreover, obtaining information on corrosion stability. The analysis specifically addresses the basic materials, namely steels in the base condition as well as in the aluminized condition, i.e. steel enriched with aluminium surface layer. The steels have been subjected to heat treatment using the aluminizing process in backfill in order to increase the amount of aluminium in the surface layer. The aluminizing process took place only in the gas phase using the solid mixture in the backfill. The used backfill as the means of aluminizing was a mixture of several types of powder consisting of 1% of Al by weight, 1% of NH4Cl by weight and 98% of Al2O3 by weight. The process was carried out at 900 ⁰C in a tube furnace and it lasted four hours. After aluminizing process, we obtained information on the development of the microstructure, carried out hardness measurements and determined the corrosion properties by means of electrochemical methods. The electrochemical properties of the steels were determined by means of linear polarization measurements, potentiodynamic measurements and electrochemical impedance spectroscopy. The electrochemical testing methods have been performed in 0.1 M NaCl solution at room temperature. Based on the results of the inspections, we examined and analysed the impact of the aluminizing on the behaviour of the handled steels with the ultimate objective of the assessment of the corrosive properties. The primary objective of the survey was to evaluate, on the basis of the electrochemical measurements carried out, the enriched surface in terms of improving the corrosion resistance. Corrosion resistance of steels has increased with alumnization, except for stainless steel X2XrNi18-9 where it increased.
Sekundarne ključne besede: Aluminizing process in backfill;diffusion;corrosion resistance;potentiodynamic measurements;electrochemical impedance spectroscopy;
Vrsta dela (COBISS): Magistrsko delo/naloga
Študijski program: 0
Konec prepovedi (OpenAIRE): 1970-01-01
Komentar na gradivo: Univ. v Ljubljani, Naravoslovnotehniška fak., Oddelek za materiale in metalurgijo
Strani: XIX, 88 f.
ID: 12046534