Browsing NTNU Open by Author "Roven, Hans Jørgen"
Now showing items 41-60 of 88
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Fatigue of Extruded AA6082 and AA7108 Alloys - The Effects of Natural Ageing Compared to Artificial Ageing
Brynjulfsen, Marte (Master thesis, 2015)Heat treatable aluminium alloys might have the potential to gain unexpected increase in mechanical properties when stored at room temperature (natural ageing) after extrusion, for long periods of time. The main aim of the ... -
Fatigue of Welded AA6082 Alloys - Effects of PWHT and Shot Peening
Utne, Sophie Caroline (Master thesis, 2013)Aluminum is a metal widely used in areas such as a construction material in buildings, transportation,oil and gas industry, in packaging for preserving food and drink, electric cables, heatexchangers and many other areas. ... -
Finite element analysis of strain distribution in ZK60 Mg alloy during cyclic extrusion and compression
Lin, Jinbao; Wang, Qudong; Liu, Manping; Chen, Yongjun; Roven, Hans Jørgen (Journal article; Peer reviewed, 2012)Finite element method was used to study the strain distribution in ZK60 Mg alloy during multi-pass cyclic extrusion and compression (CEC). In order to optimize the CEC processing, the effects of friction condition and die ... -
Freezing solute atoms in nanograined aluminum alloys via high-density vacancies
Wu, Shenghua; Søreide, Hanne-Sofie; Li, Chunan; Liu, gang; Li, Yanjun; Roven, Hans Jørgen; Sun, Jun (Peer reviewed; Journal article, 2022)Low-temperature decomposition of supersaturated solid solution into unfavorable intergranular precipitates is a long-standing bottleneck limiting the practical applications of nanograined aluminum alloys that are prepared ... -
Hierarchical structure in Al-Cu alloys to promote strength/ductility synergy
Wu, Shenghua; Li, Yanjun; Roven, Hans Jørgen; Liu, gang; Sun, Jun (Peer reviewed; Journal article, 2021)Experimental evidence demonstrated that equal channel angular pressing (ECAP) at cryogenic temperature, in comparison with ECAP at room temperature, led to promoted strength-ductility synergy in an Al-2.5wt.%Cu alloy. The ... -
Hydrides of Laves type Ti–Zr alloys with enhanced H storage capacity as advanced metal hydride battery anodes
Wijayanti, Ika Dewi; Denys, Roman Volodymyrovich; Suwarno, Suwarno; Volodin, Alexei A.; Lototskyy, Mykhaylo V.; Guzik, Matylda N.; Nei, Jean; Young, Kwo; Roven, Hans Jørgen; Yartys, Volodymyr (Peer reviewed; Journal article, 2020)The present work was focused on the studies of the effect of variation of stoichiometric composition of Ti–Zr based AB2±x Laves phase alloys by changing the ratio between A (Ti + Zr) and B (Mn + V + Fe + Ni) components ... -
Influence of polycrystalline material on crater shape optimization and roughness using low power/low-pressure direct-current glow discharge mass spectrometry
Paudel, Gagan; Khromov, Sergey; Kasik, Martin; Roven, Hans Jørgen; Di Sabatino Lundberg, Marisa (Peer reviewed; Journal article, 2020)Depth profiling is an attractive approach for analysis of non-homogeneous samples and layered materials. This application requires an optimum sputtered crater profile, which means a flat crater bottom with steep walls and ... -
Karakterisering av mikrostruktur og mekaniske egenskaper til selektiv lasersmeltet AlSi10Mg og AlSi7MgCuHf, direkte på en AlSi7MgCu støpelegering
Opøien, Elin; Skogen Brataas, Martine Sol (Master thesis, 2019)Selektiv lasersmelting (SLS) er en av flere metoder under additiv tilvirkning. Produktet bygges ved at en laser smelter pulverpartikler sammen lag for lag. Til forskjell fra de konvensjonelle metodene som støping, ekstrudering ... -
Karakterisering av mikrostruktur og mekaniske egenskaper til selektiv lasersmeltet AlSi10Mg og AlSi7MgCuHf, direkte på en AlSi7MgCu støpelegering
Skogen Brataas, Martine Sol; Opøien, Elin (Master thesis, 2019)Selektiv lasersmelting (SLS) er en av flere metoder under additiv tilvirkning. Produktet bygges ved at en laser smelter pulverpartikler sammen lag for lag. Til forskjell fra de konvensjonelle metodene som støping, ekstrudering ... -
Microstructural heterogeneity in hexagonal close-packed pure Ti processed by high-pressure torsion
Chen, Yongjun; Li, Yanjun; Walmsley, John; Gao, N; Roven, Hans Jørgen; Starink, MJ; Langdon, TG (Journal article; Peer reviewed, 2012)Microstructural evolution was studied quantitatively by electron backscattering diffraction in commercial purity Ti processed by high-pressure torsion (HPT) at room temperature. The results show that a heterogeneous ... -
Microstructure and enhanced mechanical properties of an Mg-10Gd-2Y-0.5Zr alloy processed by cyclic extrusion and compression
Peng, Tao; Wang, Qudong; Lin, Jinbao; Liu, Manping; Roven, Hans Jørgen (Journal article; Peer reviewed, 2011)The evolution of microstructure and texture of an extruded GW102K Mg alloy processed by cyclic extrusion and compression (CEC) at 450 °C were investigated. Tensile tests were performed at room temperature and strain rate ... -
Microstructure and Mechanical Properties of 6013 Aluminum Alloy Processed by a Combination of ECAP and Preaging Treatment
Jiang, Jiawei; Liu, Manping; Liu, Yang; Tang, Kai; Wang, Zibo; Li, Yichao; Yu, Yingda; Skaret, Pål Christian; Roven, Hans Jørgen (Journal article; Peer reviewed, 2017)Microstructure and mechanical properties of a 6013 Al-Mg-Si-Cu aluminum alloy processed by a combination of equal channel angular pressing (ECAP) and preaging treatment were comparatively investigated using quantitative ... -
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 and mechanical properties of the AZ31/GW103K bimetal composite rods fabricated by co-extrusion
Meng, Yunpeng; Zhang, Hua; Lin, Boyu; Wang, Lifei; Fan, Jianfeng; Lu, Liwei; Zhou, Xin; Huang, Hailiang; Zhang, Shanzhou; Roven, Hans Jørgen (Peer reviewed; Journal article, 2022)The AZ31/GW103K bimetal composite rods consisting of a soft AZ31 sleeve and a hard GW103K core were fabricated by the co-extrusion at 350 °C, 400 °C and 450 °C, and their microstructure and mechanical properties were ... -
Microstructure and texture characteristics of ZK60 Mg alloy processed by cyclic extrusion and compression
Lin, Jinbao; Wang, Qudong; Chen, Yongjun; Liu, Manping; Roven, Hans Jørgen (Journal article; Peer reviewed, 2010)The microstructure and crystallographic texture characteristics of an extruded ZK60 Mg alloy subjected to cyclic extrusion and compression (CEC) up to 8 passes at 503 K were investigated. The local crystallographic texture, ... -
Microstructure evolution of commercial pure titanium during equal channel angular pressing
Chen, Yongjun; Li, Yanjun; Walmsley, John C.; Dumoulin, S.; Skaret, Pål Christian; Roven, Hans Jørgen (Journal article; Peer reviewed, 2010)The microstructure development of commercially pure titanium during 3 and 4 passes of equal channel angular pressing (ECAP) has been investigated in detail by optical microscopy and electron backscattered diffraction (EBSD). ... -
Mikrostruktur og mekaniske egenskaper for skrueekstrudert aluminium: Karakterisering av skrueekstrudert aluminium etter ulike rensmetoder av råmaterialet
Bilsbak, Audun (Master thesis, 2012)Det er aktuelt å bruke restaluminium fra produksjonsindustrien som råmaterialet til skrueekstrudering. Restaluminiumet inneholder forurensinger som blant annet skjæreolje. Dette arbeidet har fokusert på ulike rensemetoder ... -
Multi-scale strain measurements vs. grain size in aluminium
Taghadosi, Mojtaba (Master thesis, 2011)Now days, aluminum usage is increasing in industry. This metal has good formability and mechanical properties, but combination of mechanical strength and elongation could be improved in order to enhance competition.One of ... -
Non-destructive Evaluation of Stress and Fatigue Damage in Welded Carbon Steel Specimens Using Ferrx Electromagnetic Method (FEMM)
Persvik, Øyvind Othar Aunet (Master thesis, 2012) -
Novel Zr- based AB2 Laves type Alloys as Advanced Anodes for High Energy - High Power Metal Hydride Batteries
Wijayanti, Ika Dewi (Doctoral theses at NTNU;2020:129, Doctoral thesis, 2020)Metal hydrides have been studied during the last five decades as efficient materials for various energy storage and conversion systems. Among applications, the use of metal hydrides as electrode materials is the most ...