Blar i NTNU Open på forfatter "Marthinsen, Knut"
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Effect of Microstructure on the Precipitation of β-Mg2Si during Cooling after Homogenisation of Al-Mg-Si Alloys
Hennum, Endre Asheim; Marthinsen, Knut; Tundal, Ulf Håkon (Peer reviewed; Journal article, 2024)For Al-Mg-Si alloys, cooling after homogenisation is a crucial step because the precipitation of the equilibrium β-Mg2Si phase determines the processing capabilities in subsequent steps, as well as the subsequent precipitation ... -
The Effect of Small Additions of Fe and Heavy Deformation on the Precipitation in an Al–1.1Mg–0.5Cu–0.3Si At. Pct Alloy
Thronsen, Elisabeth; Mørkeseth, Hanne; Marioara, Calin Daniel; Minakuchi, Kazuhiro; Katsumi, Tetsuya; Marthinsen, Knut; Matsuda, Kenji; Holmestad, Randi (Journal article; Peer reviewed, 2022)The effect of 0.03 and 0.08 at. pct Fe additions on the formation of secondary phases in an Al–1.1Mg–0.5Cu–0.3Si at. pct alloy was investigated. Following solution heat treatment and natural aging, the alloys were analyzed ... -
Effect of soft Bi particles on grain refinement during severe plastic deformation
Jia, Hailong; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2017)Two aluminum alloys, Al–8Zn and Al–6Bi–8Zn were subjected to equal channel angular pressing (ECAP) up to 5 passes at room temperature. The microstructural evolution and the grain refinement behavior of these alloys were ... -
Effects of Mn content and cooling conditions in a rolled AA 3005A alloy
Vårli, Erling Aares (Master thesis, 2021)Sekundærproduksjon av aluminium innebærer omsmelting av aluminiumsskrap i tillegg til tilsetninger av primæraluminium og legeringselementer. Ettersom den kjemiske sammensetningen i skrapet varierer vil dette også føre til ... -
Effects of second-phase particles on texture during softening of an Al-Mn alloy investigated by correlative microscopy
Ånes, Håkon Wiik (Doctoral theses at NTNU;2024:48, Doctoral thesis, 2024)Aluminium is the second most used metal by weight after iron, and aluminium alloys are some of the most important structural light alloys. Motivated by reducing weight, energy, and cost, many manufacturers are replacing ... -
Electromagnetically Enhanced Priming of Ceramic Foam Filters
Fritzsch, Robert (Doctoral thesis at NTNU;2016:250, Doctoral thesis, 2016)Impurities in aluminium can cause detrimental physical and chemical inhomogeneity in the final products, as well as potentially catastrophic failures. Hence, one of the key aspects during production of aluminium and its ... -
Engineering grain boundary structures of aluminium alloys and titanium by high strain/ strain rate deformation
Jia, Hailong (Doctoral theses at NTNU;2018:139, Doctoral thesis, 2018)A comprehensive study was carried out to clarify the effects of severe plastic deformation (SPD) and high strain rate deformation on various aluminium alloys and commercial purity titanium. Equal channel angular pressing ... -
Evolution in microstructure and properties during non-isothermal annealing of a cold-rolled Al-Mn-Fe-Si alloy with different microchemistry states
Huang, Ke; Engler, Olaf; Li, Yanjun; Marthinsen, Knut (Journal article, 2015)The softening behaviour during non-isothermal annealing of a cold-rolled Al–Mn–Fe–Si model alloy was studied as a function of the state of microchemistry, in terms of the solute level of Mn, size and spatial distribution ... -
Evolution in texture and its through-thickness variations in Al-Mg-Si-extrusions: experiments and modelling
Zhang, Kai; Marthinsen, Knut; Holmedal, Bjørn; Aukrust, Trond; Segatori, Antonio (Chapter, 2018)The visual appearance and mechanical properties of aluminium alloy extrusions are strongly dependent on the microstructure and texture of the extruded profiles, where the desired microstructure and texture may depend on ... -
An experimental and numerical study of the Portevin-Le Chatelier effect in an AlMg alloy
Xu, Jianbin (Doctoral theses at NTNU;2021:238, Doctoral thesis, 2021) -
Experimental Characterization and Modelling of the PLC Effect in an AlMg-Alloy
Xu, Jianbin; Holmedal, Bjørn; Hopperstad, Odd Sture; Marthinsen, Knut (Peer reviewed; Journal article, 2021)In the present work, uniaxial tension tests have been conducted to study the mechanical response of a commercial Al4.5wt%Mg alloy (AA5182). The measurements range from the strain rate of 10-4 to 100 s-1 at room temperature. ... -
First-principles study of tensile and shear strength of an Fe2Al5//Fe interface
Khalid, Muhammad Zeeshan; Friis, Jesper; Ninive, Per Harald; Marthinsen, Knut; Ringdalen, Inga Gudem; Strandlie, Are (Peer reviewed; Journal article, 2021)The interfacial strengths of a low misfit Fe2Al5//Fe interface structure found at aluminum-steel joints has been studied using density functional theory. An interface between Fe and Fe2Al5 was selected based on a criteria ... -
First-principles study of tensile and shear strength of Fe-Al and α-AlFeSi intermetallic compound interfaces
Khalid, Muhammad Zeeshan; Friis, Jesper; Ninive, Per Harald; Marthinsen, Knut; Strandlie, Are (Peer reviewed; Journal article, 2021)First-principles virtual tensile and shear strength calculations have been performed on the Fe2Al5// Fe4Al13 and -AlFeSi// Fe4Al13 interfaces. The Fast Inertial Relaxation Engine (FIRE) algorithm is used for optimizing ... -
Formation of incoherent deformation twin boundaries in a coarse-grained Al-7Mg alloy
Jin, Shenbao; Zhang, Kai; Bjørge, Ruben; Tao, NR; Marthinsen, Knut; Lu, K; Li, Yanjun (Journal article; Peer reviewed, 2015)Deformation twinning has rarely been observed in coarse grained Al and its alloys except under some extreme conditions such as ultrahigh deformation strain or strain rates. Here, we report that a significant amount of Σ3 ... -
Formation of {11-21} twin boundaries in titanium by kinking mechanism through accumulative dislocation slip
Jin, Shenbao; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2016)The twinning behavior and kinking behavior of a commercial purity Ti subjected to room temperature dynamic plastic deformation (DPD) has been studied. Three types of deformation twins, {1012}, {1122} and {1121}, have been ... -
Implementation and Testing of Numerical Models for Evolution of Microchemistry and Microstructure During Back-Annealing of Aluminium Alloys
Iversen, Jørgen Tandberg (Master thesis, 2014)Precipal and Alsoft are two separate models for simulating the effects of back-annealing on microchemistry and microstructure, respectively, in AA3xxx-type aluminium alloys (i.e Mn containing alloys). The precipitation ... -
Impurity effect of Mg on the generalized planar fault energy of Al
Zhao, Dongdong; Løvvik, Ole Martin; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2016)Generalized planar fault energy (GPFE) curves are widely used to evaluate the deformation behavior of metals and alloys. In the present work, a systematic analysis of the microscopic plastic deformation mechanism of ... -
Impurity segregation at defects in Al and Si -A theoretical DFT based study
Zhao, Dongdong (Doctoral theses at NTNU;2017:273, Doctoral thesis, 2017)Alien impurity elements favor to stay at the defects, e.g. stacking fault, grain boundary (GB) in host materials and thus influence many material properties. On basis of atomistic simulations, the present thesis puts a ... -
In-situ observations of dislocation recovery and low angle boundary formation in deformed aluminium
Ånes, Håkon Wiik; Van Helvoort, Antonius; Marthinsen, Knut (Journal article; Peer reviewed, 2019)An experimental study of the recovery of dislocations and low angle boundary formation in aluminium is presented. By combining in-situ annealing with orientation mapping in the transmission electron microscope, maps of ... -
Interface energy determination for the fully coherent β'' phase in Al-Mg-Si: making a case for a first principles based hybrid atomistic modelling scheme
Ehlers, Flemming J H; Dumoulin, Stephane; Marthinsen, Knut; Holmestad, Randi (Journal article, 2013)Multiscale modelling of hardening precipitate interfaces in alloy design This project will develop a new multiscale modelling scheme used to investigate hardening precipitate interfaces in metal alloys. The major aim is ...