Blar i NTNU Open på forfatter "Hjelen, Jarle"
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Karakterisering av deformasjonstvillinger i dupleks rustfritt stål
Kildahl, Pernille Nordmoen (Master thesis, 2014)Dannelse av deformasjonstvillinger i dupleks rustfrie stål har blitt viet lite oppmerksomhet til nå. I denne masteroppgaven har deformasjon blitt introdusert gjennom mekanisk testing for å fremprovosere tvillingdannelse i ... -
Kvantifisering av rest-austenitt i sveisesimulert SMSS og kontinuerlig EBSD karakterisering under in-situ strekktesting
Andresen, Børge Sognnæs (Master thesis, 2016)Denne oppgavene omhandler EBSD kvantifisering av rest-austenitt i sveisesimulert SMSS og utforsker i tillegg en ny metode for in-situ strekktesting hvor EBSD opptak blir gjort under kontinuerlig strekking. To ulike strategier ... -
Microstructure and mechanical properties of Al-xMg alloys processed by room temperature ECAP
Chen, Yongjun; Chai, YC; Roven, Hans Jørgen; Subbarayan, Sapthagireesh; Yu, Yingda; Hjelen, Jarle (Journal article; Peer reviewed, 2012)Microstructure development and mechanical properties of Al–xMg alloys (x = 0, 1, 5–10 wt%), processed by ECAP at room temperature, have been investigated. The results show that the microstructures of Al–xMg alloys are ... -
Microstructure Characterisation of Bainitic HSLA Steel for Pressure Vessels
Lopez, Vanessa Valle (Master thesis, 2014)The microstructure and mechanical properties in the midsection of a high thickness HSLA bainitic steel, was investigated in this master thesis. A homogeneous microstructure and good mechanical properties can be difficult to ... -
Microstructure Evolution in Super Duplex Stainless Steels Containing σ-Phase Investigated at Low-Temperature Using In Situ SEM/EBSD Tensile Testing
Paulsen, Christian Oen; Broks, Runar Larsen; Karlsen, Morten; Hjelen, Jarle; Westermann, Ida (Journal article; Peer reviewed, 2018)An in situ scanning electron microscope (SEM) study was conducted on a super duplex stainless steel (SDSS) containing 0%, 5% and 10% σ-phase. The material was heat treated at 850 °C for 12 min and 15 min, respectively, to ... -
Mikrostrukturutvikling i superdupleks rustfritt stål og effekten av prøvepreparering på identifisering og kvantifisering av sigmafase gjennom EBSD-karakterisering
Kleppen, Jannicke (Master thesis, 2018)Superdupleks rustfritt stål benyttes ofte i konstruksjoner lokalisert i korrosive miljø på grunn av høy mekanisk styrke og god korrosjonsmotstand. På grunn av et høyt innhold av legeringselementer er stålet utsatt for ... -
Optimization of EBSD parameters for ultra-fast characterization
Chen, Yongjun; Hjelen, Jarle; Subbarayan, Sapthagireesh; Roven, Hans Jørgen (Journal article; Peer reviewed, 2012)Ultra-fast pattern acquisition of electron backscatter diffraction and offline indexing could become a dominant technique over online electron backscatter diffraction to investigate the microstructures of a wide range of ... -
Orientation and Projection Center Refinement for EBSD Indexing in Python
Lervik, Lars Andreas Hastad (Master thesis, 2021)I dette arbeidet er et sett med algoritmer for forbedring av krystallorientering og projeksjonssenter estimater spesielt etter, men ikke begrenset til, dictionary indexing av EBSD mønster presentert. Algoritmene er utviklet ... -
Phase Transformation Study of X70 Steel by EBSD during In Situ Heating and Quenching
Hansen, Kristoffer Werner (Master thesis, 2012)Arctic steels, like the API X70 steel explored in this master thesis, are developed to withstand very low temperatures, with a ductile/brittle transition temperature below −60◦C. However, during welding, brittle phases ... -
Processing and indexing of electron backscatter patterns using open-source software
Ånes, Håkon Wiik; Hjelen, Jarle; Sørensen, Bjørn Eske; Van Helvoort, Antonius; Marthinsen, Knut (Peer reviewed; Journal article, 2020)A new method to increase the signal-to-noise ratio S/N of electron backscatter patterns (EBSPs) based upon principal component analysis (PCA) is presented. The PCA denoising method is applied to ten scans of EBSPs from the ... -
Quantitative study of grain refinement in Al-Mg alloy processed by equal channel angular pressing at cryogenic temperature
Chen, Yongjun; Roven, Hans Jørgen; Subbarayan, Sapthagireesh; Skaret, Pål Christian; Hjelen, Jarle (Journal article; Peer reviewed, 2011)Strain induced grain refinement of an Al–1 wt.% Mg alloy processed by equal channel angular pressing (ECAP) at cryogenic temperature is investigated quantitatively. The results show that both mean grain and subgrain sizes ... -
The Effect of Refined Prior β-grains on the Final Microstructure and Strain Response in Ti-6Al-4V produced by Wire-Fed Plasma Deposition - Investigated by combined EBSD and In-Situ Tensile Experiments
Arbo, Siri Marthe (Master thesis, 2015)In this master thesis, the focus has been on a Ti-6Al-4V specimen produced by Norsk Titanium s patented wire-fed plasma deposition technique, under conditions promoting the break up of the traditional large columnar β-grains ... -
Utvikling av metode for bråkjøling i SEM og in situ EBSD-karakterisering av fasetransformasjoner i F 70 stål.
Sætran, Truls Gruben (Master thesis, 2012)Fasetransformasjoner som skjer ved sveising av F 70 arktisk stål fører til at ugunstige mikrostrukturer oppstår i den varmepåvirkede sonen av grunnmaterialet (HAZ). Ved gjentatt oppvarming av HAZ vil det kunne dannes områder ...