Blar i NTNU Open på forfatter "Roven, Hans Jørgen"
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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 ... -
Optimization of Electrical Conductivity in Screw Extruded Wires
Langelandsvik, Geir (Master thesis, 2017)The novel production method of screw extrusion was used to produce an electrical conducting wire of commercial pure aluminium. To optimize electrical properties, effects of impurity atoms in solid solution were examined ... -
Optimization of Electrical Conductivity in Screw Extruded Wires: The effect of aluminium oxide particles on screw extruded wires of pure aluminium
Edvardsen, Martine Hanshus (Master thesis, 2021)Elektrisk ledende tråder av en aluminium-matrise kompositt (aluminium matrix composite (AMC)) ble produsert gjennom kontinuerlig skrueekstrudering av metaller (Metal continuous screw extrusion (MCSE)). Kompositten bestod ... -
Porosity Reduction and Characterization of Aluminium Components Produced by Additive Manufacturing
Djuraev, Alisher (Master thesis, 2017)Selective laser melting (SLM) is a relatively novel method used to produce metallic parts directly from computer models by selectively fusing metallic powder. The production is fundamentally different from traditional ... -
Preliminary Investigations on the Manufacture of Al-AZ31 Bimetallic Composites by the Screw Extrusion Process
Pedersen, Bodil Drange (Master thesis, 2013)The development of bimetals, or metallic composites, has in recent years been given increased attention. The motivation behind the development of bimetals is that, by combining two dissimilar metals it is possible to obtain ... -
Prominent role of multi-scale microstructural heterogeneities on superplastic deformation of a high solid solution Al–7Mg alloy
Zha, Min; Zhang, Hongmin; Jia, Hailong; Gao, Yipeng; Jin, Shenbao; Sha, Gang; Bjørge, Ruben; Mathiesen, Ragnvald; Roven, Hans Jørgen; Wang, Hui-Yuan; Li, Yanjun (Peer reviewed; Journal article, 2021)Achieving high superplasticity in single-phase Al alloys remains a challenge, since the fine-grained structure required for superplastic deformation coarsens rapidly in the absence of dispersed second-phase particles during ... -
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 ... -
Recycling of Aluminum Scrap by Severe Plastic Deformation
Cui, Jirang; Guo, Wei; Roven, Hans Jørgen; Wang, Qudong; Chen, Yongjun; Peng, Tao (Journal article; Peer reviewed, 2011)The production of primary aluminum is an energy costly process. With the global warming being of concern, the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive ... -
Recycling of automotive aluminum
Cui, Jirang; Roven, Hans Jørgen (Journal article; Peer reviewed, 2010)With the global warming of concern, the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive because of its economic and environmental benefits. In this work, ... -
Revealing slip-induced extension twinning behaviors dominated by micro deformation in a magnesium alloy
Zhou, Bijin; Wang, Leyun; Jin, Peipeng; Jia, Hailong; Roven, Hans Jørgen; Zeng, Xiaoqin; Li, Yanjun (Peer reviewed; Journal article, 2020)In this study, an in situ SEM/EBSD study on slip-induced extension twinning (S→T) behaviors of a Mg–Y alloy was conducted. It shows that the S→T process cannot be well explained using the classical geometrical compatibility ... -
Review of Aluminum Alloy Development for Wire Arc Additive Manufacturing
Langelandsvik, Geir; Akselsen, Odd Magne; Furu, Trond; Roven, Hans Jørgen (Peer reviewed; Journal article, 2021)Processing of aluminum alloys by wire arc additive manufacturing (WAAM) gained significant attention from industry and academia in the last decade. With the possibility to create large and relatively complex parts at low ... -
Screw Extrusion from various Binary Al-XMg Feed Materials - Effects of Heat Treatment on Microstructure
Berulfsen, Tarjei (Master thesis, 2016)Three direct chill (DC) cast aluminium-magnesium (Al-Mg) alloys, with 5, 8, and 10 wt% magnesium, have been used as base materials. These base materials were either rapidly solidified by melt spinning, or granulated by ... -
Screw Extrusion of Light Metals: Development of materials, characterization and process analysis
Skorpen, Kristian Grøtta (Doctoral theses at NTNU;2018:218, Doctoral thesis, 2018)The presented work highlights the possibilities inherent in a new method for continuous extrusion, i.e. hereafter named metal continuous screw extrusion (MCSE). This was done by expanding the knowledge of the process itself, ... -
Special nanostructures in Al-Mg alloys subjected to high pressure torsion
Liu, Manping; Roven, Hans Jørgen; Liu, XT; Murashkin, Maxim; Valiev, Ruslan Z.; Ungar, Tamas; Balogh, Lavente (Journal article; Peer reviewed, 2010)Deformation twins and stacking faults were observed in nanostructure Al-Mg alloys subjected to high pressure torsion. These observations are surprising because deformation twinnings have never been observed in their ... -
Stabilizing a severely deformed Al–7Mg alloy with a multimodal grain structure via Mg solute segregation
Zha, Min; Wang, Huiyuan; Li, Yanjun; Roven, Hans Jørgen (Peer reviewed; Journal article, 2021)Single-phase Al–Mg alloys processed by severe plastic deformation (SPD) usually suffer from unsatisfactory thermal stability at moderate to high temperatures with recrystallization occurring and obvious grain coarsening. ... -
Strength and Ductility in two Ultra High Strength Al-Alloys AA2196 and AA7090
Kyllingstad, Runar Braut (Master thesis, 2019)I denne masteroppgaven blir de mekaniske egenskapene, kornstrukturen og anisotropien i tredjegenerasjons Al-Li legeringen AA2196 undersøkt etter en foreslått varmebehandlingsprosess. Hensikten med rapporten er å undersøke ... -
Strengthening and toughening mechanisms of an ultrafine grained Mg-Gd-Y-Zr alloy processed by cyclic extrusion and compression
Wang, Qudong; Mu, Yongliang; Lin, Jinbao; Zhang, Li; Roven, Hans Jørgen (Journal article; Peer reviewed, 2017)Cyclic extrusion and compression (CEC) was implemented to process the Mg-Gd-Y-Zr alloy. Microstructure characters, including the matrix grain, precipitates and texture evolution, were tried to correlate with the mechanical ... -
The Applicability of Aluminium Alloys as Reinforcement Material in Concrete Constructions
Amundsen, Hans Sigurd (Master thesis, 2018)This thesis is a part of the DARE2C research project. The research projects primary objective is to develop a more environmentally-friendly type of concrete where more than 55% of the cement is replaced with less CO2(g) ... -
The Effect of Rapid Solidification on Ti-Zr Alloys for Application in Ni-MH Battery Anodes
Mølmen, Live (Master thesis, 2018)Metal hydrides find applications in the storage of hydrogen and also as anode materials for the nickel-metal hydride batteries(Ni-MH). The properties of these materials can be tuned by selecting appropriate elemental ... -
The effect of thickness and compaction on the recovery of aluminium in recycling of foils in salt flux
Philipson, Harald (Master thesis, 2020)I Norge förbränns mer än 40 000 ton aluminiumförpackningar årligen. Återvinning av denna mängd aluminiumförpackningar skulle spara 1,5 TWh energi och hundratusentals ton av koldioxidutsläpp. Det mycket svårare att återvinna ...