Blar i NTNU Open på forfatter "Marthinsen, Knut"
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Orientation relationships of phase transformation in α-Al12Mn3Si pseudomorphs after plate-like Al6Mn precipitate in an AA3004 Al-Mn based alloy
Nakayasua, Hiroki; Kobayashi, Equo; Sato, Tatsuo; Holmestad, Randi; Marthinsen, Knut (Journal article; Peer reviewed, 2017)The phase transformation in the plate-like precipitates of Al6Mn in an AA3004 Al-Mn based alloy, which was prepared by a chemical extraction technique, was investigated using transmission electron microscopy. The boiling-phenol ... -
Precipitation hardening in two Al-Mn-Cu-Mg-Si alloys aimed for brazed heat exchangers
Alvem, Andreas (Master thesis, 2019)FA7850 and FA7933 er to forskjellige aluminiumslegeringer med herdingspotensial. Beregninger viser at en høyere andel av herdningspresipitater skal være tilstede i FA7933 enn i FA7850 ved likevekt ved 100 °C. En høyere ... -
Precipitation, strength and work hardening of age hardened aluminium alloys
Ryen, Øyvind; Holmedal, Bjørn; Marthinsen, Knut; Furu, Trond (Journal article; Peer reviewed, 2015)The strength and work hardening of age hardened AA6063 and AA6082 alloys have been investigated in terms of a detailed characterization of precipitate and dislocation structures obtained by TEM and SEM. Tensile and compression ... -
Process- and Alloy Development of Recyclable Aluminium Alloys: Recovery and Recrystallization Behavior of a Selection of AlMn-model Alloys
Flatøy, Jarl Erik Morsund (Master thesis, 2011)A study of the effect of various amounts of manganese in solid solution on the recovery and recrystallization behavior of an AlMn-alloy, for different annealing conditions after different degrees of deformation (cold ... -
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 ... -
Quantifying the grain boundary segregation strengthening induced by post-ECAP aging in an Al-5Cu alloy
Jia, Hailong; Bjørge, Ruben; Cao, Lingfei; Hui, Song; Marthinsen, Knut; Li, Yanjun (Journal article, 2018)Hardening on annealing (HOA) has been frequently observed in nanostructured metals and alloys. For nanostructured materials obtained by severe plastic deformation (SPD), HOA has been attributed to the reduction of dislocation ... -
Recovery Kinetics in High Purity and Commercial Purity Aluminium Alloys
Bunkholt, Sindre; Marthinsen, Knut; Nes, Erik Aasmund (Journal article, 2013)Motivated by improving current softening models for recycle friendly alloys, softening was investigated in high purity and commercial purity aluminium alloys. Utilizing the electron backscatter diffraction (EBSD) technique, ... -
Recrystallisation Behaviour in Extruded Profiles of Non-Dispersoid Containing Al-Mg-Si Alloys
Paulsen, Christian Oen (Master thesis, 2015)Hot extrusion of non-dispersoid containing aluminium alloys commonly ends with a fully or partially recrystallised grain structure. However, the recrystallisation mechanisms, whether static or dynamic (taking place during ... -
Revealing abnormal {11-21} twins in commercial purity Ti subjected to split Hopkinson pressure bar
Jia, Hailong; Marthinsen, Knut; Li, Yanjun (Journal article, 2019)The deformation behavior of Ti alloys during conventional deformation, such as rolling and compression,have been extensively investigated, while it is less understood during high strain rate deformation. In thepresent work, ... -
Segregation of Mg, Cu and their effects on the strength of Al S5 (210) [001] symmetrical tilt grain boundary
Zhao, Dongdong; Løvvik, Ole Martin; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2018)Alien elemental segregation can pronouncedly change the grain boundary properties. Systematic first-principles calculations were performed to investigate the Mg and Cu segregation behavior at Σ5 (210)[001] symmetrical tilt ... -
A simple method enabling efficient quantitative analysis of the Portevin–Le Chatelier band characteristics
Xu, Jianbin; Liu, Lei; Hopperstad, Odd Sture; Holmedal, Bjørn; Manik, Tomas; Marthinsen, Knut (Peer reviewed; Journal article, 2022)Localized deformation bands are often observed in materials exhibiting the Portevin–Le Chatelier (PLC) effect. However, efficient quantitative analysis of PLC bands remains challenging. A novel method is thus proposed in ... -
Soft particles assisted grain refinement and strengthening of an Al-Bi-Zn alloy subjected to ECAP
Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Mathiesen, Ragnvald; Li, Yanjun (Journal article; Peer reviewed, 2017)With the aim to improve the strength of potential Pb-free Al-Bi based bearing alloys, an Al-6Bi-8Zn alloy was subjected to equal channel angular pressing (ECAP). To reveal the roles played by the soft Bi particles, an ... -
Softening Behaviour of Selected Commercially Pure Aluminium Model Alloys
Sande, Gunnar (Master thesis, 2012)A characterization of the softening behaviour of four different commercially pure aluminium alloys has been carried out. The work is related to the MOREAL project (Modelling towards value-added recycling friendly aluminium ... -
Stress-strain relations for age hardened AlMgSi alloys, measured with necking corrections and modelled based on TEM characterization
Lu, Feng (Doctoral theses at NTNU;2021:182, Doctoral thesis, 2021)Age hardening Al-Mg-Si(-Cu) alloys, like other aluminium alloys, are increasingly utilized due to the combination of cost-saving, easy fabrication, and good mechanical properties. Yield strength and work hardening are ... -
Subgrain structures characterized by electron backscatter diffraction (EBSD)
Bunkholt, Sindre; Marthinsen, Knut; Nes, Erik Aasmund (Journal article; Peer reviewed, 2014)Subgrain structures are frequently characterized by the electron backscatter diffraction (EBSD) method, which is both accurate and provides good statistics. This is essential to better understand the subgrain growth ... -
Tailoring microstructure and texture of annealed Al-Mn alloy through the variation of homogenization and prior cold deformation strain
Fang, X.W.; Xiao, H.; Marthinsen, Knut; Belyakov, Andrey; Fang, X.Y.; Huang, Ke (Peer reviewed; Journal article, 2020)The grain structures and crystallographic textures desired for various applications of aluminium alloys are usually modified by recrystallization during annealing. In this study, the interactions between recrystallization ... -
Texture and Microstructure Evolution during Extrusion of AlMgSi-Alloys
Fylkesnes, Helge (Master thesis, 2016)The main objective of this thesis is to contribute to a better understanding of the microstructure and texture evolution during extrusion of AlMgSi alloys. The textures and microstructures in AA6082 were analysed after ... -
The deformation and work hardening behaviour of a SPD processed Al-5Cu alloy
Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2017)An Al-5wt.%Cu alloy supersaturated with Cu in solid solution was subjected to equal channel angular pressing (ECAP). The microstructuralevolution was systematically investigated by backscattered electron (BSE)imaging, ... -
The deformation and work hardening behaviour of a SPD processed Al-5Cu alloy
Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2017)An Al-5 wt.% Cu alloy supersaturated with Cu in solid solution was subjected to equal channel angular pressing (ECAP). The microstructural evolution was systematically investigated by backscattered electron (BSE) imaging, ... -
The double-edge effect of second-phase particles on the recrystallization behaviour and associated mechanical properties of metallic materials
Huang, Ke; Marthinsen, Knut; Zhao, Qinglong; Loge, Roland E. (Journal article; Peer reviewed, 2018)Most industrial alloys contain a matrix phase and dispersed second-phase particles. Several thermomechanical processing (TMP) steps are usually needed to produce a final product, during which recrystallization and its ...